Tests pour évaluer le biais de non-réponse dans les enquêtes Section 5. Discussion

Dans le présent article, nous avons considéré des tests de détection du biais de non-réponse après l’utilisation de la poststratification ou de la pondération par l’inverse de la propension à répondre. Les arguments utilisés dans les théorèmes pourraient être étendus à des méthodes similaires qui sont utilisées pour corriger le biais de non-réponse, telles que le ratissage (raking), qui effectue une poststratification itérative sur des totaux de population de marge, ou le calage, qui ajuste les poids de manière que les totaux de population estimés concordent avec les totaux de contrôle pour un ensemble de variables auxiliaires. Haziza et Lesage (2016) soutiennent que l’utilisation d’une procédure en deux étapes de pondération par la propension à répondre suivie d’un calage offre plus de protection contre le biais de non-réponse qu’uniquement le calage en une seule étape, parce que ce dernier implique un modèle reliant les propensions à répondre et les variables de calage, et que le modèle peut être mal spécifié. Les tests proposés dans le présent article pourraient être étendus à des situations où l’on utilise à la fois la pondération par la propension à répondre et la poststratification, ou être utilisés séparément pour évaluer le biais éliminé à chaque étape d’un processus en deux étapes.

Nous avons employé le jackknife pour l’estimation de la variance par rééchantillonnage. Cependant, tous les estimateurs sont des fonctions lisses des totaux de population, si bien que d’autres estimateurs de la variance par rééchantillonnage, tels que les répliques répétées équilibrées ou le bootstrap pourraient également être utilisés.

Une difficulté de l’évaluation du biais de non-réponse tient à la quantité limitée d’information disponible sur l’échantillon sélectionné. Pour certaines enquêtes, toute l’information auxiliaire disponible est utilisée ou prise en considération pour former les poststrates, les classes de pondération par ratissage ou les pondérations par l’inverse de la propension à répondre. Pour les caractéristiques utilisées dans la poststratification, l’estimateur poststratifié ne possède ni variance ni biais, de sorte que tester ces caractéristiques ou des caractéristiques étroitement associées ne permettra pas de découvrir le biais de non-réponse dans d’autres variables étudiées. Les variables auxiliaires qui ne sont pas utilisées pour les corrections de la non-réponse sont souvent omises uniquement parce qu’elles n’ont pas été sélectionnées dans la méthode de choix du modèle utilisé pour former les poststrates ou pour choisir les variables pour la régression logistique, et cette situation se produit habituellement parce que leur pouvoir explicatif pour la prédiction de l’indicateur de réponse est faible après que les autres variables aient été incluses dans le modèle. Pour les enquêtes dont la base de sondage contient moins d’information, il pourrait être possible d’obtenir des données auxiliaires en provenance d’autres sources, comme des dossiers administratifs associés aux adresses des répondants ou des paradonnées. Il est important de s’assurer que les variables utilisées pour tester le biais de non-réponse soient enregistrées de manière cohérente pour les répondants et les non-répondants. Par exemple, si y MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaaaa@356C@ est l’évaluation de la présence d’enfants dans le ménage faite dans la rue par l’intervieweur, cette évaluation initiale doit être utilisée pour les répondants ainsi que les non-répondants : l’évaluation utilisée dans l’analyse du biais de non-réponse ne doit pas être mise à jour après que l’intervieweur confirme le nombre réel d’enfants dans un ménage répondant.

Après avoir testé les variables disponibles pour la présence d’un biais de non-réponse, nous ne savons toujours pas si les ajustements ont éliminé le biais pour les variables de résultat qui ne sont disponibles que pour les répondants. Abraham, Helms et Presser (2009), ainsi que Kohut, Keeter, Doherty, Dimock et Christian (2012) ont constaté que les estimations du bénévolat et de la participation civique sont plus élevées dans les enquêtes à faible taux de réponse que pour la Current Population Survey, ce qui indique que les ajustements de la pondération n’éliminent pas le biais pour les variables d’engagement civique, alors qu’ils semblent corriger le biais pour les variables démographiques et la propriété du logement. Toutefois, tester une grande gamme de variables auxiliaires pour la présence d’un biais résiduel peut donner plus de confiance dans les résultats d’une enquête sur les variables non testées, ou peut témoigner de préoccupations au sujet des inférences faites d’après l’enquête pour les variables d’intérêt. Nous recommandons que les concepteurs d’enquêtes planifient celles-ci en pensant à l’évaluation du biais de non-réponse, et recueillent des renseignements supplémentaires sur l’échantillon sélectionné dans la mesure du possible. En général, plus on peut recueillir d’information sur l’échantillon sélectionné, mieux c’est.

La comparaison des estimations en utilisant différents ensembles de poids peut présenter un intérêt particulier quand on étudie des stratégies axées sur des plans de collecte dynamique ou adaptatifs, telles que celles décrites dans Groves et Heeringa (2006) et résumées dans Tourangeau, Brick, Lohr et Li (2016). Dans ces stratégies, les phases ultérieures du plan sont modifiées en se servant de l’information recueillie au cours des phases de collecte antérieures. Une stratégie avec plan de collecte dynamique pourrait consister à estimer les taux de réponse après la première phase de l’enquête, puis à répartir les ressources à la deuxième phase de manière à égaliser les taux entre les sous-groupes d’intérêt. Dans une comparaison expérimentale de différentes stratégies avec plan de collecte dynamique, il pourrait être intéressant d’évaluer le biais de non-réponse estimé pour les diverses stratégies. Riddles, Marker, Rizzo, Wiley et Zukerberg (2015) ont comparé les estimations pondérées de la non-réponse pour différents seuils d’exclusion dans la U.S. Schools and Staffing Survey afin de voir si les estimations variaient avec une troncation plus précoce de la collecte des données.

Les résultats des théorèmes 1 à 5 sont exprimés pour des échantillons probabilistes. Or, l’intérêt augmente pour l’usage d’échantillons non probabilistes en vue d’étudier les populations (Baker, Brick, Bates, Battaglia, Couper, Dever, Gile et Tourangeau 2013). Les partisans des échantillons non probabilistes soutiennent que, avec des taux de réponse parfois inférieurs à 10 %, un grand échantillon non probabiliste peu coûteux peut avoir une plus petite erreur quadratique moyenne qu’un petit échantillon probabiliste. Les mêmes méthodes de poststratification et de pondération par l’inverse de la propension à répondre sont habituellement appliquées aux échantillons non probabilistes. Les tests proposés dans le présent article peuvent être adaptés en vue de les utiliser avec ces échantillons, à condition que l’information auxiliaire soit connue pour une série d’individus qui peuvent remplacer la base de sondage. Dans le cas d’une enquête en ligne, il pourrait être possible de comparer les caractéristiques des personnes qui visitent la page Web à celles des personnes qui répondent à l’enquête. Les travaux de recherche doivent se poursuivre dans ce domaine.

Remerciements

Les auteurs remercient les examinateurs de leurs suggestions constructives qui leur ont permis d’améliorer l’article.

Annexe

Le lemme qui suit montre que la variabilité additionnelle due au mécanisme de réponse stochastique est O ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4tamaabm aabaWaaSGbaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaGcbaGaamOB aaaaaiaawIcacaGLPaaacaGGUaaaaa@3A4B@

Lemme 1. Supposons que les hypothèses (A3) et (A5) sont satisfaites et que | q h i k | Q MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaqWaaeaaca aMc8UaamyCamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaaGPa VdGaay5bSlaawIa7aiabgsMiJkaadgfaaaa@4128@  pour toute unité ( h i k ) U . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaaca WGObGaamyAaiaadUgaaiaawIcacaGLPaaacqGHiiIZcaWGvbGaaiOl aaaa@3BD2@  Alors

E [ V ( h i k U Z h i k w h i k q h i k r h i k | Z ) ] = O ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyramaadm aabaGaamOvamaabmaabaWaaqGaaeaadaaeqbqaaiaadQfadaWgaaWc baGaamiAaiaadMgacaWGRbaabeaakiaadEhadaWgaaWcbaGaamiAai aadMgacaWGRbaabeaakiaadghadaWgaaWcbaGaamiAaiaadMgacaWG RbaabeaakiaadkhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaaae aacaWGObGaamyAaiaadUgacqGHiiIZcaWGvbaabeqdcqGHris5aaGc caGLiWoacaWHAbaacaGLOaGaayzkaaaacaGLBbGaayzxaaGaaGypai aad+eadaqadaqaamaalyaabaGaamytamaaCaaaleqabaGaaGOmaaaa aOqaaiaad6gaaaaacaGLOaGaayzkaaGaaGOlaaaa@59BD@

Preuve. En vertu de l’hypothèse (A5),

| E [ V ( h i k U Z h i k w h i k q h i k r h i k | Z ) ] | = | E [ h = 1 H i = 1 N h k = 1 M h i p = 1 M h i Z h i k Z h i p w h i k w h i p Cov ( r h i k , r h i p ) q h i k q h i p ] | Q 2 E [ h = 1 H i = 1 N h k = 1 M h i p = 1 M h i Z h i k Z h i p w h i k w h i p ] = Q 2 h = 1 H i = 1 N h k = 1 M h i p = 1 M h i P [ ( h i ) S ] P [ k S h i p S h i ] w h i k w h i p = O ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqrVfpC0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabqGaaa aabaWaaqWaaeaacaaMe8UaamyramaadmaabaGaamOvamaabmaabaWa aqGaaeaadaaeqbqaaiaadQfadaWgaaWcbaGaamiAaiaadMgacaWGRb aabeaakiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaa dghadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadkhadaWgaa WcbaGaamiAaiaadMgacaWGRbaabeaaaeaacaWGObGaamyAaiaadUga cqGHiiIZcaWGvbaabeqdcqGHris5aaGccaGLiWoacaWHAbaacaGLOa GaayzkaaaacaGLBbGaayzxaaGaaGjbVdGaay5bSlaawIa7aaqaaiaa i2dadaabdaqaaiaaysW7caWGfbWaamWaaeaadaaeWbqabSqaaiaadI gacaaI9aGaaGymaaqaaiaadIeaa0GaeyyeIuoakmaaqahabeWcbaGa amyAaiaai2dacaaIXaaabaGaamOtamaaBaaameaacaWGObaabeaaa0 GaeyyeIuoakmaaqahabeWcbaGaam4Aaiaai2dacaaIXaaabaGaamyt amaaBaaameaacaWGObGaamyAaaqabaaaniabggHiLdGcdaaeWbqabS qaaiaadchacaaI9aGaaGymaaqaaiaad2eadaWgaaadbaGaamiAaiaa dMgaaeqaaaqdcqGHris5aOGaaGPaVlaadQfadaWgaaWcbaGaamiAai aadMgacaWGRbaabeaakiaadQfadaWgaaWcbaGaamiAaiaadMgacaWG WbaabeaakiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaaki aadEhadaWgaaWcbaGaamiAaiaadMgacaWGWbaabeaakiaaboeacaqG VbGaaeODamaabmaabaGaamOCamaaBaaaleaacaWGObGaamyAaiaadU gaaeqaaOGaaGilaiaadkhadaWgaaWcbaGaamiAaiaadMgacaWGWbaa beaaaOGaayjkaiaawMcaaiaadghadaWgaaWcbaGaamiAaiaadMgaca WGRbaabeaakiaadghadaWgaaWcbaGaamiAaiaadMgacaWGWbaabeaa aOGaay5waiaaw2faaiaaysW7aiaawEa7caGLiWoaaeaaaeaacqGHKj YOcaWGrbWaaWbaaSqabeaacaaIYaaaaOGaamyramaadmaabaWaaabC aeqaleaacaWGObGaaGypaiaaigdaaeaacaWGibaaniabggHiLdGcda aeWbqabSqaaiaadMgacaaI9aGaaGymaaqaaiaad6eadaWgaaadbaGa amiAaaqabaaaniabggHiLdGcdaaeWbqabSqaaiaadUgacaaI9aGaaG ymaaqaaiaad2eadaWgaaadbaGaamiAaiaadMgaaeqaaaqdcqGHris5 aOWaaabCaeaacaWGAbWaaSbaaSqaaiaadIgacaWGPbGaam4Aaaqaba GccaWGAbWaaSbaaSqaaiaadIgacaWGPbGaamiCaaqabaGccaWG3bWa aSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGccaWG3bWaaSbaaSqaai aadIgacaWGPbGaamiCaaqabaaabaGaamiCaiaai2dacaaIXaaabaGa amytamaaBaaameaacaWGObGaamyAaaqabaaaniabggHiLdaakiaawU facaGLDbaaaeaaaeaacaaI9aGaamyuamaaCaaaleqabaGaaGOmaaaa kmaaqahabeWcbaGaamiAaiaai2dacaaIXaaabaGaamisaaqdcqGHri s5aOWaaabCaeqaleaacaWGPbGaaGypaiaaigdaaeaacaWGobWaaSba aWqaaiaadIgaaeqaaaqdcqGHris5aOWaaabCaeqaleaacaWGRbGaaG ypaiaaigdaaeaacaWGnbWaaSbaaWqaaiaadIgacaWGPbaabeaaa0Ga eyyeIuoakmaaqahabaGaamiuamaadmaabaWaaeWaaeaacaWGObGaam yAaaGaayjkaiaawMcaaiabgIGiolaadofaaiaawUfacaGLDbaacaWG qbWaamWaaeaacaWGRbGaeyicI4Saam4uamaaBaaaleaacaWGObGaam yAaaqabaGccaaISaGaamiCaiabgIGiolaadofadaWgaaWcbaGaamiA aiaadMgaaeqaaaGccaGLBbGaayzxaaGaam4DamaaBaaaleaacaWGOb GaamyAaiaadUgaaeqaaOGaam4DamaaBaaaleaacaWGObGaamyAaiaa dchaaeqaaaqaaiaadchacaaI9aGaaGymaaqaaiaad2eadaWgaaadba GaamiAaiaadMgaaeqaaaqdcqGHris5aaGcbaaabaGaaGypaiaad+ea daqadaqaamaalyaabaGaamytamaaCaaaleqabaGaaGOmaaaaaOqaai aad6gaaaaacaGLOaGaayzkaaGaaGOlaaaaaaa@1905@

La dernière ligne découle implicitement de l’hypothèse (A3).

Preuve du théorème 1. De (2.4), il découle que

V 1 ( θ ^ ) = V [ c = 1 C 1 p c ( Y ^ c R Y ¯ c R ( M ^ c R M c R ) ) Y ^ S S ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIXaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaaI9aGaamOvamaadmaabaWaaabCaeqaleaacaWGJbGaaGypai aaigdaaeaacaWGdbaaniabggHiLdGcdaWcaaqaaiaaigdaaeaacaWG WbWaaSbaaSqaaiaadogaaeqaaaaakmaabmaabaGabmywayaajaWaa0 baaSqaaiaadogaaeaacaWGsbaaaOGaeyOeI0IabmywayaaraWaa0ba aSqaaiaadogaaeaacaWGsbaaaOWaaeWaaeaaceWGnbGbaKaadaqhaa WcbaGaam4yaaqaaiaadkfaaaGccqGHsislcaWGnbWaa0baaSqaaiaa dogaaeaacaWGsbaaaaGccaGLOaGaayzkaaaacaGLOaGaayzkaaGaey OeI0IabmywayaajaWaaSbaaSqaaiaadofacaWGtbaabeaaaOGaay5w aiaaw2faaaaa@5996@

et

V 2 ( θ ^ ) = V [ c = 1 C T ^ c p c ] + 2 Cov [ c = 1 C T ^ c p c , c = 1 C ( y ¯ c R Y ¯ c R ) M ^ c R p c Y ^ S S ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaaI9aGaamOvamaadmaabaWaaabCaeqaleaacaWGJbGaaGypai aaigdaaeaacaWGdbaaniabggHiLdGcdaWcaaqaaiqadsfagaqcamaa BaaaleaacaWGJbaabeaaaOqaaiaadchadaWgaaWcbaGaam4yaaqaba aaaaGccaGLBbGaayzxaaGaey4kaSIaaGOmaiaaysW7caaMc8Uaae4q aiaab+gacaqG2bWaamWaaeaadaaeWbqabSqaaiaadogacaaI9aGaaG ymaaqaaiaadoeaa0GaeyyeIuoakmaalaaabaGabmivayaajaWaaSba aSqaaiaadogaaeqaaaGcbaGaamiCamaaBaaaleaacaWGJbaabeaaaa GccaaISaWaaabCaeqaleaacaWGJbGaaGypaiaaigdaaeaacaWGdbaa niabggHiLdGcdaWcaaqaamaabmaabaGabmyEayaaraWaa0baaSqaai aadogaaeaacaWGsbaaaOGaeyOeI0IabmywayaaraWaa0baaSqaaiaa dogaaeaacaWGsbaaaaGccaGLOaGaayzkaaGabmytayaajaWaa0baaS qaaiaadogaaeaacaWGsbaaaaGcbaGaamiCamaaBaaaleaacaWGJbaa beaaaaGccqGHsislceWGzbGbaKaadaWgaaWcbaGaam4uaiaadofaae qaaaGccaGLBbGaayzxaaGaaGOlaaaa@71DF@

Le terme principal se simplifie en

V 1 ( θ ^ ) = V [ h i k U Z h i k w h i k c = 1 C δ c h i k { r h i k p c ( y h i k Y ¯ c R ) y h i k } ] = V [ E [ h i k U Z h i k w h i k c = 1 C δ c h i k { r h i k p c ( y h i k Y ¯ c R ) y h i k } | Z ] ] + E [ V [ h i k U Z h i k w h i k c = 1 C δ c h i k { r h i k p c ( y h i k Y ¯ c R ) y h i k } | Z ] ] = V ( h i k U Z h i k w h i k e R h i k ) + E [ V [ h i k U Z h i k w h i k c = 1 C δ c h i k r h i k p c ( y h i k Y ¯ c R ) | Z ] ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqrVfpC0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabqGaaa aabaGaamOvamaaBaaaleaacaaIXaaabeaakmaabmaabaGafqiUdeNb aKaaaiaawIcacaGLPaaaaeaacaaI9aGaamOvamaadmaabaWaaabuae aacaWGAbWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGccaWG3bWa aSbaaSqaaiaadIgacaWGPbGaam4AaaqabaaabaGaamiAaiaadMgaca WGRbGaeyicI4Saamyvaaqab0GaeyyeIuoakmaaqahabaGaeqiTdq2a aSbaaSqaaiaadogacaWGObGaamyAaiaadUgaaeqaaaqaaiaadogaca aI9aGaaGymaaqaaiaadoeaa0GaeyyeIuoakmaacmaabaWaaSaaaeaa caWGYbWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaaakeaacaWGWb WaaSbaaSqaaiaadogaaeqaaaaakmaabmaabaGaamyEamaaBaaaleaa caWGObGaamyAaiaadUgaaeqaaOGaeyOeI0IabmywayaaraWaa0baaS qaaiaadogaaeaacaWGsbaaaaGccaGLOaGaayzkaaGaeyOeI0IaamyE amaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaaGccaGL7bGaayzFaa aacaGLBbGaayzxaaaabaaabaGaaGypaiaadAfadaWadaqaaiaadwea daWadaqaamaaeiaabaWaaabuaeqaleaacaWGObGaamyAaiaadUgacq GHiiIZcaWGvbaabeqdcqGHris5aOGaamOwamaaBaaaleaacaWGObGa amyAaiaadUgaaeqaaOGaam4DamaaBaaaleaacaWGObGaamyAaiaadU gaaeqaaOWaaabCaeaacqaH0oazdaWgaaWcbaGaam4yaiaadIgacaWG PbGaam4AaaqabaaabaGaam4yaiaai2dacaaIXaaabaGaam4qaaqdcq GHris5aOWaaiWaaeaadaWcaaqaaiaadkhadaWgaaWcbaGaamiAaiaa dMgacaWGRbaabeaaaOqaaiaadchadaWgaaWcbaGaam4yaaqabaaaaO WaaeWaaeaacaWG5bWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGc cqGHsislceWGzbGbaebadaqhaaWcbaGaam4yaaqaaiaadkfaaaaaki aawIcacaGLPaaacqGHsislcaWG5bWaaSbaaSqaaiaadIgacaWGPbGa am4AaaqabaaakiaawUhacaGL9baacaaMc8oacaGLiWoacaaMc8UaaC OwaaGaay5waiaaw2faaaGaay5waiaaw2faaaqaaaqaaiaaywW7cqGH RaWkcaWGfbWaamWaaeaacaWGwbWaamWaaeaadaabcaqaamaaqafabe WcbaGaamiAaiaadMgacaWGRbGaeyicI4Saamyvaaqab0GaeyyeIuoa kiaadQfadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadEhada WgaaWcbaGaamiAaiaadMgacaWGRbaabeaakmaaqahabaGaeqiTdq2a aSbaaSqaaiaadogacaWGObGaamyAaiaadUgaaeqaaaqaaiaadogaca aI9aGaaGymaaqaaiaadoeaa0GaeyyeIuoakmaacmaabaWaaSaaaeaa caWGYbWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaaakeaacaWGWb WaaSbaaSqaaiaadogaaeqaaaaakmaabmaabaGaamyEamaaBaaaleaa caWGObGaamyAaiaadUgaaeqaaOGaeyOeI0IabmywayaaraWaa0baaS qaaiaadogaaeaacaWGsbaaaaGccaGLOaGaayzkaaGaeyOeI0IaamyE amaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaaGccaGL7bGaayzFaa GaaGPaVdGaayjcSdGaaGPaVlaahQfaaiaawUfacaGLDbaaaiaawUfa caGLDbaaaeaaaeaacaaI9aGaamOvamaabmaabaWaaabuaeqaleaaca WGObGaamyAaiaadUgacqGHiiIZcaWGvbaabeqdcqGHris5aOGaamOw amaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaam4DamaaBaaale aacaWGObGaamyAaiaadUgaaeqaaOGaamyzamaaBaaaleaacaWGsbGa amiAaiaadMgacaWGRbaabeaaaOGaayjkaiaawMcaaiabgUcaRiaadw eadaWadaqaaiaadAfadaWadaqaamaaeiaabaWaaabuaeqaleaacaWG ObGaamyAaiaadUgacqGHiiIZcaWGvbaabeqdcqGHris5aOGaamOwam aaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaam4DamaaBaaaleaa caWGObGaamyAaiaadUgaaeqaaOWaaabCaeaacqaH0oazdaWgaaWcba Gaam4yaiaadIgacaWGPbGaam4AaaqabaaabaGaam4yaiaai2dacaaI XaaabaGaam4qaaqdcqGHris5aOWaaSaaaeaacaWGYbWaaSbaaSqaai aadIgacaWGPbGaam4AaaqabaaakeaacaWGWbWaaSbaaSqaaiaadoga aeqaaaaakmaabmaabaGaamyEamaaBaaaleaacaWGObGaamyAaiaadU gaaeqaaOGaeyOeI0IabmywayaaraWaa0baaSqaaiaadogaaeaacaWG sbaaaaGccaGLOaGaayzkaaGaaGPaVdGaayjcSdGaaGPaVlaahQfaai aawUfacaGLDbaaaiaawUfacaGLDbaacaaIUaaaaaaa@35F7@

Le lemme 1 et l’hypothèse (A4), qui garantit que 1 / p c MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSGbaeaaca aIXaaabaGaamiCamaaBaaaleaacaWGJbaabeaaaaaaaa@3748@ est bornée, implique que le deuxième terme est   O ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4tamaabm aabaWaaSGbaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaGcbaGaamOB aaaaaiaawIcacaGLPaaacaGGUaaaaa@3A4B@

Pour montrer que V 2 ( θ ^ ) = o ( M 2 / n ) , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaaI9aGaam4BamaabmaabaWaaSGbaeaacaWGnbWaaWbaaSqabe aacaaIYaaaaaGcbaGaamOBaaaaaiaawIcacaGLPaaacaGGSaaaaa@404C@ notons qu’en vertu de (A4) et de l’inégalité de Cauchy-Schwarz,

V [ T ^ c p c ] 1 ε 2 c = 1 C d = 1 C V [ ( y ¯ c R Y ¯ c R ) ( M ^ c R M c R ) ] V [ ( y ¯ d R Y ¯ d R ) ( M ^ d R M d R ) ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaadm aabaWaaSaaaeaaceWGubGbaKaadaWgaaWcbaGaam4yaaqabaaakeaa caWGWbWaaSbaaSqaaiaadogaaeqaaaaaaOGaay5waiaaw2faaiabgs MiJoaalaaabaGaaGymaaqaaiabew7aLnaaCaaaleqabaGaaGOmaaaa aaGcdaaeWbqabSqaaiaadogacaaI9aGaaGymaaqaaiaadoeaa0Gaey yeIuoakmaaqahabeWcbaGaamizaiaai2dacaaIXaaabaGaam4qaaqd cqGHris5aOWaaOaaaeaacaWGwbWaamWaaeaadaqadaqaaiqadMhaga qeamaaDaaaleaacaWGJbaabaGaamOuaaaakiabgkHiTiqadMfagaqe amaaDaaaleaacaWGJbaabaGaamOuaaaaaOGaayjkaiaawMcaamaabm aabaGabmytayaajaWaa0baaSqaaiaadogaaeaacaWGsbaaaOGaeyOe I0IaamytamaaDaaaleaacaWGJbaabaGaamOuaaaaaOGaayjkaiaawM caaaGaay5waiaaw2faaiaadAfadaWadaqaamaabmaabaGabmyEayaa raWaa0baaSqaaiaadsgaaeaacaWGsbaaaOGaeyOeI0Iabmywayaara Waa0baaSqaaiaadsgaaeaacaWGsbaaaaGccaGLOaGaayzkaaWaaeWa aeaaceWGnbGbaKaadaqhaaWcbaGaamizaaqaaiaadkfaaaGccqGHsi slcaWGnbWaa0baaSqaaiaadsgaaeaacaWGsbaaaaGccaGLOaGaayzk aaaacaGLBbGaayzxaaaaleqaaOGaaGOlaaaa@7300@

L’hypothèse (A2) implique (Fuller 2009, théorème 1.3.2) que

n [ y ¯ c R Y ¯ c R M ^ c R / M c R 1 ] N ( 0 , Σ c ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaOaaaeaaca WGUbaaleqaaOWaamWaaeaafaqabeGabaaabaGabmyEayaaraWaa0ba aSqaaiaadogaaeaacaWGsbaaaOGaeyOeI0IabmywayaaraWaa0baaS qaaiaadogaaeaacaWGsbaaaaGcbaWaaSGbaeaaceWGnbGbaKaadaqh aaWcbaGaam4yaaqaaiaadkfaaaaakeaacaWGnbWaa0baaSqaaiaado gaaeaacaWGsbaaaOGaeyOeI0IaaGymaaaaaaaacaGLBbGaayzxaaGa eyOKH4QaamOtamaabmaabaGaaCimaiaaiYcacaWHJoWaaSbaaSqaai aadogaaeqaaaGccaGLOaGaayzkaaaaaa@4DCC@

quand n , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOBaiabgk ziUkabg6HiLkaacYcaaaa@396F@ Σ c MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaC4OdmaaBa aaleaacaWGJbaabeaaaaa@36B1@ est une matrice définie non négative. Conséquemment,

( n M c R ) 2 V [ ( y ¯ c R Y ¯ c R ) ( M ^ c R M c R ) ] Σ c [ 1,1 ] Σ c [ 2,2 ] + 2 ( Σ c [ 1,2 ] ) 2 ; MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaada Wcaaqaaiaad6gaaeaacaWGnbWaa0baaSqaaiaadogaaeaacaWGsbaa aaaaaOGaayjkaiaawMcaamaaCaaaleqabaGaaGOmaaaakiaadAfada WadaqaamaabmaabaGabmyEayaaraWaa0baaSqaaiaadogaaeaacaWG sbaaaOGaeyOeI0IabmywayaaraWaa0baaSqaaiaadogaaeaacaWGsb aaaaGccaGLOaGaayzkaaWaaeWaaeaaceWGnbGbaKaadaqhaaWcbaGa am4yaaqaaiaadkfaaaGccqGHsislcaWGnbWaa0baaSqaaiaadogaae aacaWGsbaaaaGccaGLOaGaayzkaaaacaGLBbGaayzxaaGaeyOKH4Qa aC4OdmaaBaaaleaacaWGJbaabeaakiaaiUfacaaIXaGaaGilaiaaig dacaaIDbGaaGjbVlaaho6adaWgaaWcbaGaam4yaaqabaGcdaWadaqa aiaaikdacaaISaGaaGOmaaGaay5waiaaw2faaiabgUcaRiaaikdada qadaqaaiaaho6adaWgaaWcbaGaam4yaaqabaGcdaWadaqaaiaaigda caaISaGaaGOmaaGaay5waiaaw2faaaGaayjkaiaawMcaamaaCaaale qabaGaaGOmaaaakiaaiUdaaaa@697C@

l’application de l’inégalité de Cauchy-Schwarz au terme de covariance implique que V 2 ( θ ^ ) = o ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaaI9aGaam4BamaabmaabaWaaSGbaeaacaWGnbWaaWbaaSqabe aacaaIYaaaaaGcbaGaamOBaaaaaiaawIcacaGLPaaacaGGUaaaaa@404E@

Preuve du théorème 2. Nous montrons que

V ˜ ( θ ) = h = 1 H n h n h 1 i S h ( b ˜ h i b ˜ h ) 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaia WaaeWaaeaacqaH4oqCaiaawIcacaGLPaaacaaI9aWaaabmaeqaleaa caWGObGaaGypaiaaigdaaeaacaWGibaaniabggHiLdGcdaWcaaqaai aad6gadaWgaaWcbaGaamiAaaqabaaakeaacaWGUbWaaSbaaSqaaiaa dIgaaeqaaOGaeyOeI0IaaGymaaaadaaeqaqabSqaaiaadMgacqGHii IZcaWGtbWaaSbaaWqaaiaadIgaaeqaaaWcbeqdcqGHris5aOWaaeWa aeaaceWGIbGbaGaadaWgaaWcbaGaamiAaiaadMgaaeqaaOGaeyOeI0 IabmOyayaaiaWaaSbaaSqaaiaadIgaaeqaaaGccaGLOaGaayzkaaWa aWbaaSqabeaacaaIYaaaaaaa@5366@

est convergent, où

b ˜ h i = k S h i w h i k { c = 1 C 1 p c r h i k δ c h i k ( y h i k Y ¯ c R ) y h i k } = k S h i w h i k e ˜ r h i k MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOyayaaia WaaSbaaSqaaiaadIgacaWGPbaabeaakiaai2dadaaeqbqabSqaaiaa dUgacqGHiiIZcaWGtbWaaSbaaWqaaiaadIgacaWGPbaabeaaaSqab0 GaeyyeIuoakiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaa kmaacmaabaWaaabCaeqaleaacaWGJbGaaGypaiaaigdaaeaacaWGdb aaniabggHiLdGcdaWcaaqaaiaaigdaaeaacaWGWbWaaSbaaSqaaiaa dogaaeqaaaaakiaadkhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabe aakiabes7aKnaaBaaaleaacaWGJbGaamiAaiaadMgacaWGRbaabeaa kmaabmaabaGaamyEamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaO GaeyOeI0IabmywayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaaGc caGLOaGaayzkaaGaeyOeI0IaamyEamaaBaaaleaacaWGObGaamyAai aadUgaaeqaaaGccaGL7bGaayzFaaGaaGypamaaqafabeWcbaGaam4A aiabgIGiolaadofadaWgaaadbaGaamiAaiaadMgaaeqaaaWcbeqdcq GHris5aOGaam4DamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGa bmyzayaaiaWaaSbaaSqaaiaadkhacaWGObGaamyAaiaadUgaaeqaaa aa@775E@

et b ˜ h = i S h b ˜ h i / n h . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOyayaaia WaaSbaaSqaaiaadIgaaeqaaOGaaGypamaaqababeWcbaGaamyAaiab gIGiolaadofadaWgaaadbaGaamiAaaqabaaaleqaniabggHiLdGcda WcgaqaaiqadkgagaacamaaBaaaleaacaWGObGaamyAaaqabaaakeaa caWGUbWaaSbaaSqaaiaadIgaaeqaaaaakiaac6caaaa@4390@ Les arguments donnés dans Yung et Rao (2000) impliquent alors que ( n / M 2 ) [ V ˜ ( θ ) V ^ ( θ ) ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaada Wcgaqaaiaad6gaaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaaaaOGa ayjkaiaawMcaamaadmaabaGabmOvayaaiaWaaeWaaeaacqaH4oqCai aawIcacaGLPaaacqGHsislceWGwbGbaKaadaqadaqaaiabeI7aXbGa ayjkaiaawMcaaaGaay5waiaaw2faaaaa@43F7@ converge vers zéro en probabilité.

Notons que

E [ b ˜ h i | Z ] = k S h i w h i k e R h i k , MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyramaadm aabaGabmOyayaaiaWaaSbaaSqaaiaadIgacaWGPbaabeaakmaaeeaa baGaaGPaVlaahQfaaiaawEa7aaGaay5waiaaw2faaiaai2dadaaeqb qaaiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadwga daWgaaWcbaGaamOuaiaadIgacaWGPbGaam4AaaqabaaabaGaam4Aai abgIGiolaadofadaWgaaadbaGaamiAaiaadMgaaeqaaaWcbeqdcqGH ris5aOGaaGilaaaa@4FE5@

E [ b ˜ h i 2 | Z ] = E [ ( k S h i w h i k { c = 1 C 1 p c [ R h i k + r h i k R h i k ] δ c h i k ( y h i k Y ¯ c R ) y h i k } ) 2 | Z ] = ( k S h i w h i k e R h i k ) 2 + V ( k S h i w h i k e ˜ r h i k | Z ) , MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaadweadaWadaqaaiqadkgagaacamaaDaaaleaacaWGObGaamyA aaqaaiaaikdaaaGcdaabbaqaaiaaykW7caWHAbaacaGLhWoaaiaawU facaGLDbaaaeaacaaI9aGaamyramaadmaabaWaaqGaaeaadaqadaqa amaaqafabaGaam4DamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaa qaaiaadUgacqGHiiIZcaWGtbWaaSbaaWqaaiaadIgacaWGPbaabeaa aSqab0GaeyyeIuoakmaacmaabaWaaabCaeqaleaacaWGJbGaaGypai aaigdaaeaacaWGdbaaniabggHiLdGcdaWcaaqaaiaaigdaaeaacaWG WbWaaSbaaSqaaiaadogaaeqaaaaakmaadmaabaGaamOuamaaBaaale aacaWGObGaamyAaiaadUgaaeqaaOGaey4kaSIaamOCamaaBaaaleaa caWGObGaamyAaiaadUgaaeqaaOGaeyOeI0IaamOuamaaBaaaleaaca WGObGaamyAaiaadUgaaeqaaaGccaGLBbGaayzxaaGaeqiTdq2aaSba aSqaaiaadogacaWGObGaamyAaiaadUgaaeqaaOWaaeWaaeaacaWG5b WaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGccqGHsislceWGzbGb aebadaqhaaWcbaGaam4yaaqaaiaadkfaaaaakiaawIcacaGLPaaacq GHsislcaWG5bWaaSbaaSqaaiaadIgacaWGPbGaam4Aaaqabaaakiaa wUhacaGL9baaaiaawIcacaGLPaaadaahaaWcbeqaaiaaikdaaaGcca aMc8oacaGLiWoacaaMc8UaaCOwaaGaay5waiaaw2faaaqaaaqaaiaa i2dadaqadaqaamaaqafabeWcbaGaam4AaiabgIGiolaadofadaWgaa adbaGaamiAaiaadMgaaeqaaaWcbeqdcqGHris5aOGaam4DamaaBaaa leaacaWGObGaamyAaiaadUgaaeqaaOGaamyzamaaBaaaleaacaWGsb GaamiAaiaadMgacaWGRbaabeaaaOGaayjkaiaawMcaamaaCaaaleqa baGaaGOmaaaakiabgUcaRiaadAfadaqadaqaamaaeiaabaWaaabuae qaleaacaWGRbGaeyicI4Saam4uamaaBaaameaacaWGObGaamyAaaqa baaaleqaniabggHiLdGccaWG3bWaaSbaaSqaaiaadIgacaWGPbGaam 4AaaqabaGcceWGLbGbaGaadaWgaaWcbaGaamOCaiaadIgacaWGPbGa am4AaaqabaaakiaawIa7aiaaykW7caWHAbaacaGLOaGaayzkaaGaaG ilaaaaaaa@AFDC@

et

E [ b ˜ h 2 | Z ] = 1 n h 2 E [ i S h b h i 2 + i S h j i b h i b h j | Z ] = 1 n h 2 i S h V ( k S h i w h i k e ˜ r h i k | Z ) + ( 1 n h i S h k S h i w h i k e R h i k ) 2 . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaadweadaWadaqaamaaeiaabaGabmOyayaaiaWaa0baaSqaaiaa dIgaaeaacaaIYaaaaaGccaGLiWoacaaMc8UaaCOwaaGaay5waiaaw2 faaaqaaiaai2dadaWcaaqaaiaaigdaaeaacaWGUbWaa0baaSqaaiaa dIgaaeaacaaIYaaaaaaakiaadweadaWadaqaamaaqafabeWcbaGaam yAaiabgIGiolaadofadaWgaaadbaGaamiAaaqabaaaleqaniabggHi LdGccaWGIbWaa0baaSqaaiaadIgacaWGPbaabaGaaGOmaaaakiabgU caRmaaeiaabaWaaabuaeqaleaacaWGPbGaeyicI4Saam4uamaaBaaa meaacaWGObaabeaaaSqab0GaeyyeIuoakmaaqafabeWcbaGaamOAai abgcMi5kaadMgaaeqaniabggHiLdGccaWGIbWaaSbaaSqaaiaadIga caWGPbaabeaakiaadkgadaWgaaWcbaGaamiAaiaadQgaaeqaaaGcca GLiWoacaaMc8UaaCOwaaGaay5waiaaw2faaaqaaaqaaiaai2dadaWc aaqaaiaaigdaaeaacaWGUbWaa0baaSqaaiaadIgaaeaacaaIYaaaaa aakmaaqafabaGaamOvaaWcbaGaamyAaiabgIGiolaadofadaWgaaad baGaamiAaaqabaaaleqaniabggHiLdGcdaqadaqaamaaeiaabaWaaa buaeqaleaacaWGRbGaeyicI4Saam4uamaaBaaameaacaWGObGaamyA aaqabaaaleqaniabggHiLdGccaWG3bWaaSbaaSqaaiaadIgacaWGPb Gaam4AaaqabaGcceWGLbGbaGaadaWgaaWcbaGaamOCaiaadIgacaWG PbGaam4AaaqabaaakiaawIa7aiaaykW7caWHAbaacaGLOaGaayzkaa Gaey4kaSYaaeWaaeaadaWcaaqaaiaaigdaaeaacaWGUbWaaSbaaSqa aiaadIgaaeqaaaaakmaaqafabeWcbaGaamyAaiabgIGiolaadofada WgaaadbaGaamiAaaqabaaaleqaniabggHiLdGcdaaeqbqabSqaaiaa dUgacqGHiiIZcaWGtbWaaSbaaWqaaiaadIgacaWGPbaabeaaaSqab0 GaeyyeIuoakiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaa kiaadwgadaWgaaWcbaGaamOuaiaadIgacaWGPbGaam4Aaaqabaaaki aawIcacaGLPaaadaahaaWcbeqaaiaaikdaaaGccaaIUaaaaaaa@A68F@

Cela implique que

E [ i S h [ b ˜ h i b ˜ h ] 2 ] = E [ i S h ( k S h i w h i k e R h i k ) 2 1 n h ( i S h k S h i w h i k e R h i k ) 2 ] + ( 1 1 n h ) E [ i S h V ( k S h i w h i k e ˜ r h i k y h i k | Z ) ] , MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaadweadaWadaqaamaaqafabeWcbaGaamyAaiabgIGiolaadofa daWgaaadbaGaamiAaaqabaaaleqaniabggHiLdGcdaWadaqaaiqadk gagaacamaaBaaaleaacaWGObGaamyAaaqabaGccqGHsislceWGIbGb aGaadaWgaaWcbaGaamiAaaqabaaakiaawUfacaGLDbaadaahaaWcbe qaaiaaikdaaaaakiaawUfacaGLDbaaaeaacaaI9aGaamyramaadmaa baWaaabuaeqaleaacaWGPbGaeyicI4Saam4uamaaBaaameaacaWGOb aabeaaaSqab0GaeyyeIuoakmaabmaabaWaaabuaeqaleaacaWGRbGa eyicI4Saam4uamaaBaaameaacaWGObGaamyAaaqabaaaleqaniabgg HiLdGccaWG3bWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGccaWG LbWaaSbaaSqaaiaadkfacaWGObGaamyAaiaadUgaaeqaaaGccaGLOa GaayzkaaWaaWbaaSqabeaacaaIYaaaaOGaeyOeI0YaaSaaaeaacaaI XaaabaGaamOBamaaBaaaleaacaWGObaabeaaaaGcdaqadaqaamaaqa fabeWcbaGaamyAaiabgIGiolaadofadaWgaaadbaGaamiAaaqabaaa leqaniabggHiLdGcdaaeqbqabSqaaiaadUgacqGHiiIZcaWGtbWaaS baaWqaaiaadIgacaWGPbaabeaaaSqab0GaeyyeIuoakiaadEhadaWg aaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadwgadaWgaaWcbaGaam OuaiaadIgacaWGPbGaam4AaaqabaaakiaawIcacaGLPaaadaahaaWc beqaaiaaikdaaaaakiaawUfacaGLDbaaaeaaaeaacaaMf8Uaey4kaS YaaeWaaeaacaaIXaGaeyOeI0YaaSaaaeaacaaIXaaabaGaamOBamaa BaaaleaacaWGObaabeaaaaaakiaawIcacaGLPaaacaWGfbWaamWaae aadaaeqbqaaiaadAfadaqadaqaamaaeiaabaWaaabuaeqaleaacaWG RbGaeyicI4Saam4uamaaBaaameaacaWGObGaamyAaaqabaaaleqani abggHiLdGccaWG3bWaaSbaaSqaaiaadIgacaWGPbGaam4AaaqabaGc ceWGLbGbaGaadaWgaaWcbaGaamOCaiaadIgacaWGPbGaam4Aaaqaba GccqGHsislcaWG5bWaaSbaaSqaaiaadIgacaWGPbGaam4Aaaqabaaa kiaawIa7aiaaykW7caWHAbaacaGLOaGaayzkaaaaleaacaWGPbGaey icI4Saam4uamaaBaaameaacaWGObaabeaaaSqab0GaeyyeIuoaaOGa ay5waiaaw2faaiaaiYcaaaaaaa@AF41@

de sorte que V ^ L ( θ ^ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOvayaaja WaaSbaaSqaaiaadYeaaeqaaOWaaeWaaeaacuaH4oqCgaqcaaGaayjk aiaawMcaaaaa@39AF@ est un estimateur approximativement sans biais de V 1 ( θ ^ ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIXaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaGGUaaaaa@3A3B@ La convergence découle de (A2), qui implique la normalité asymptotique, et de la loi des grands nombres.

Preuve du théorème 3. Pour c d , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4yaiabgc Mi5kaadsgacaGGSaaaaa@38B6@

Cov [ ( y ¯ c R Y ¯ c R ) ( M ^ c R M c R ) , ( y ¯ d R Y ¯ d R ) ( M ^ d R M d R ) ] = o ( M 2 / n 2 ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaae4qaiaab+ gacaqG2bWaamWaaeaadaqadaqaaiqadMhagaqeamaaDaaaleaacaWG JbaabaGaamOuaaaakiabgkHiTiqadMfagaqeamaaDaaaleaacaWGJb aabaGaamOuaaaaaOGaayjkaiaawMcaamaabmaabaGabmytayaajaWa a0baaSqaaiaadogaaeaacaWGsbaaaOGaeyOeI0IaamytamaaDaaale aacaWGJbaabaGaamOuaaaaaOGaayjkaiaawMcaaiaaiYcadaqadaqa aiqadMhagaqeamaaDaaaleaacaWGKbaabaGaamOuaaaakiabgkHiTi qadMfagaqeamaaDaaaleaacaWGKbaabaGaamOuaaaaaOGaayjkaiaa wMcaamaabmaabaGabmytayaajaWaa0baaSqaaiaadsgaaeaacaWGsb aaaOGaeyOeI0IaamytamaaDaaaleaacaWGKbaabaGaamOuaaaaaOGa ayjkaiaawMcaaaGaay5waiaaw2faaiaai2dacaWGVbWaaeWaaeaada Wcgaqaaiaad2eadaahaaWcbeqaaiaaikdaaaaakeaacaWGUbWaaWba aSqabeaacaaIYaaaaaaaaOGaayjkaiaawMcaaaaa@61D7@

parce que E [ ( y ¯ c R Y ¯ c R ) ( y ¯ d R Y ¯ d R ) ] = o ( n 1 ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyramaadm aabaWaaeWaaeaaceWG5bGbaebadaqhaaWcbaGaam4yaaqaaiaadkfa aaGccqGHsislceWGzbGbaebadaqhaaWcbaGaam4yaaqaaiaadkfaaa aakiaawIcacaGLPaaadaqadaqaaiqadMhagaqeamaaDaaaleaacaWG KbaabaGaamOuaaaakiabgkHiTiqadMfagaqeamaaDaaaleaacaWGKb aabaGaamOuaaaaaOGaayjkaiaawMcaaaGaay5waiaaw2faaiaai2da caWGVbWaaeWaaeaacaWGUbWaaWbaaSqabeaacqGHsislcaaIXaaaaa GccaGLOaGaayzkaaaaaa@4E1E@ pour l’échantillonnage aléatoire simple (équation (4.26) de Lohr 2010). Par conséquent,

V ( c = 1 C T ^ c p c ) = c = 1 C d = 1 C 1 p c 1 p d Cov [ ( y ¯ c R Y ¯ c R ) ( M ^ c R M c R ) , ( y ¯ d R Y ¯ d R ) ( M ^ d R M d R ) ] = c = 1 C 1 p c 2 V [ y ¯ c R Y ¯ c R ] V [ M ^ c R M c R ] + o ( M 2 / n 2 ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaadAfadaqadaqaamaaqahabeWcbaGaam4yaiaai2dacaaIXaaa baGaam4qaaqdcqGHris5aOWaaSaaaeaaceWGubGbaKaadaWgaaWcba Gaam4yaaqabaaakeaacaWGWbWaaSbaaSqaaiaadogaaeqaaaaaaOGa ayjkaiaawMcaaaqaaiaai2dadaaeWbqabSqaaiaadogacaaI9aGaaG ymaaqaaiaadoeaa0GaeyyeIuoakmaaqahabeWcbaGaamizaiaai2da caaIXaaabaGaam4qaaqdcqGHris5aOWaaSaaaeaacaaIXaaabaGaam iCamaaBaaaleaacaWGJbaabeaaaaGcdaWcaaqaaiaaigdaaeaacaWG WbWaaSbaaSqaaiaadsgaaeqaaaaakiaaboeacaqGVbGaaeODamaadm aabaWaaeWaaeaaceWG5bGbaebadaqhaaWcbaGaam4yaaqaaiaadkfa aaGccqGHsislceWGzbGbaebadaqhaaWcbaGaam4yaaqaaiaadkfaaa aakiaawIcacaGLPaaadaqadaqaaiqad2eagaqcamaaDaaaleaacaWG JbaabaGaamOuaaaakiabgkHiTiaad2eadaqhaaWcbaGaam4yaaqaai aadkfaaaaakiaawIcacaGLPaaacaaISaWaaeWaaeaaceWG5bGbaeba daqhaaWcbaGaamizaaqaaiaadkfaaaGccqGHsislceWGzbGbaebada qhaaWcbaGaamizaaqaaiaadkfaaaaakiaawIcacaGLPaaadaqadaqa aiqad2eagaqcamaaDaaaleaacaWGKbaabaGaamOuaaaakiabgkHiTi aad2eadaqhaaWcbaGaamizaaqaaiaadkfaaaaakiaawIcacaGLPaaa aiaawUfacaGLDbaaaeaaaeaacaaI9aWaaabCaeqaleaacaWGJbGaaG ypaiaaigdaaeaacaWGdbaaniabggHiLdGcdaWcaaqaaiaaigdaaeaa caWGWbWaa0baaSqaaiaadogaaeaacaaIYaaaaaaakiaadAfadaWada qaaiqadMhagaqeamaaDaaaleaacaWGJbaabaGaamOuaaaakiabgkHi TiqadMfagaqeamaaDaaaleaacaWGJbaabaGaamOuaaaaaOGaay5wai aaw2faaiaadAfadaWadaqaaiqad2eagaqcamaaDaaaleaacaWGJbaa baGaamOuaaaakiabgkHiTiaad2eadaqhaaWcbaGaam4yaaqaaiaadk faaaaakiaawUfacaGLDbaacqGHRaWkcaWGVbWaaeWaaeaadaWcgaqa aiaad2eadaahaaWcbeqaaiaaikdaaaaakeaacaWGUbWaaWbaaSqabe aacaaIYaaaaaaaaOGaayjkaiaawMcaaiaai6caaaaaaa@9D37@

Le deuxième terme de V 2 ( θ ^ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL Paaaaaa@398A@ est:

2 Cov [ c = 1 C T ^ c p c , c = 1 C ( y ¯ c R Y ¯ c R ) M ^ c R p c Y ^ S S ] = 2 c = 1 C d = 1 C 1 p c p d Cov [ T ^ c , ( y ¯ d R Y ¯ d R ) M ^ d R p d M ^ d R y ¯ d R p d Y ^ d N R ] = 2 c = 1 C 1 p c 2 Cov [ ( y ¯ c R Y ¯ c R ) ( M ^ c R M c R ) , ( 1 p c ) y ¯ c R M ^ c R Y ¯ c R M ^ c R p c Y ^ c N R ] + o ( M 2 n 2 ) = 2 c = 1 C p c 1 p c 2 V [ y ¯ c R Y ¯ c R ] V [ M ^ c R M c R ] + o ( M 2 n 2 ) . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqrVipC0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabqqaaa aabaGaaGOmaiaaysW7caaMc8Uaae4qaiaab+gacaqG2bWaamWaaeaa daaeWbqabSqaaiaadogacaaI9aGaaGymaaqaaiaadoeaa0GaeyyeIu oakmaalaaabaGabmivayaajaWaaSbaaSqaaiaadogaaeqaaaGcbaGa amiCamaaBaaaleaacaWGJbaabeaaaaGccaaISaWaaabCaeqaleaaca WGJbGaaGypaiaaigdaaeaacaWGdbaaniabggHiLdGcdaWcaaqaamaa bmaabaGabmyEayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaOGaey OeI0IabmywayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaaGccaGL OaGaayzkaaGabmytayaajaWaa0baaSqaaiaadogaaeaacaWGsbaaaa GcbaGaamiCamaaBaaaleaacaWGJbaabeaaaaGccqGHsislceWGzbGb aKaadaWgaaWcbaGaam4uaiaadofaaeqaaaGccaGLBbGaayzxaaaaba GaaGzbVlaaywW7caaMf8UaaGzbVlaaywW7caaI9aGaaGOmamaaqaha beWcbaGaam4yaiaai2dacaaIXaaabaGaam4qaaqdcqGHris5aOWaaa bCaeqaleaacaWGKbGaaGypaiaaigdaaeaacaWGdbaaniabggHiLdGc daWcaaqaaiaaigdaaeaacaWGWbWaaSbaaSqaaiaadogaaeqaaOGaam iCamaaBaaaleaacaWGKbaabeaaaaGccaqGdbGaae4BaiaabAhadaWa daqaaiqadsfagaqcamaaBaaaleaacaWGJbaabeaakiaaiYcadaqada qaaiqadMhagaqeamaaDaaaleaacaWGKbaabaGaamOuaaaakiabgkHi TiqadMfagaqeamaaDaaaleaacaWGKbaabaGaamOuaaaaaOGaayjkai aawMcaaiqad2eagaqcamaaDaaaleaacaWGKbaabaGaamOuaaaakiab gkHiTiaadchadaWgaaWcbaGaamizaaqabaGcceWGnbGbaKaadaqhaa WcbaGaamizaaqaaiaadkfaaaGcceWG5bGbaebadaqhaaWcbaGaamiz aaqaaiaadkfaaaGccqGHsislcaWGWbWaaSbaaSqaaiaadsgaaeqaaO GabmywayaajaWaa0baaSqaaiaadsgaaeaacaWGobGaamOuaaaaaOGa ay5waiaaw2faaaqaaiaaywW7caaMf8UaaGzbVlaaywW7caaMf8UaaG ypaiaaikdadaaeWbqabSqaaiaadogacaaI9aGaaGymaaqaaiaadoea a0GaeyyeIuoakmaalaaabaGaaGymaaqaaiaadchadaqhaaWcbaGaam 4yaaqaaiaaikdaaaaaaOGaae4qaiaab+gacaqG2bWaamWaaeaacqGH sisldaqadaqaaiqadMhagaqeamaaDaaaleaacaWGJbaabaGaamOuaa aakiabgkHiTiqadMfagaqeamaaDaaaleaacaWGJbaabaGaamOuaaaa aOGaayjkaiaawMcaamaabmaabaGabmytayaajaWaa0baaSqaaiaado gaaeaacaWGsbaaaOGaeyOeI0IaamytamaaDaaaleaacaWGJbaabaGa amOuaaaaaOGaayjkaiaawMcaaiaaiYcadaqadaqaaiaaigdacqGHsi slcaWGWbWaaSbaaSqaaiaadogaaeqaaaGccaGLOaGaayzkaaGabmyE ayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaOGabmytayaajaWaa0 baaSqaaiaadogaaeaacaWGsbaaaOGaeyOeI0IabmywayaaraWaa0ba aSqaaiaadogaaeaacaWGsbaaaOGabmytayaajaWaa0baaSqaaiaado gaaeaacaWGsbaaaOGaeyOeI0IaamiCamaaBaaaleaacaWGJbaabeaa kiqadMfagaqcamaaDaaaleaacaWGJbaabaGaamOtaiaadkfaaaaaki aawUfacaGLDbaacqGHRaWkcaWGVbWaaeWaaeaadaWcaaqaaiaad2ea daahaaWcbeqaaiaaikdaaaaakeaacaWGUbWaaWbaaSqabeaacaaIYa aaaaaaaOGaayjkaiaawMcaaaqaaiaaywW7caaMf8UaaGzbVlaaywW7 caaMf8UaaGypaiaaikdadaaeWbqabSqaaiaadogacaaI9aGaaGymaa qaaiaadoeaa0GaeyyeIuoakmaalaaabaGaamiCamaaBaaaleaacaWG JbaabeaakiabgkHiTiaaigdaaeaacaWGWbWaa0baaSqaaiaadogaae aacaaIYaaaaaaakiaadAfadaWadaqaaiqadMhagaqeamaaDaaaleaa caWGJbaabaGaamOuaaaakiabgkHiTiqadMfagaqeamaaDaaaleaaca WGJbaabaGaamOuaaaaaOGaay5waiaaw2faaiaadAfadaWadaqaaiqa d2eagaqcamaaDaaaleaacaWGJbaabaGaamOuaaaakiabgkHiTiaad2 eadaqhaaWcbaGaam4yaaqaaiaadkfaaaaakiaawUfacaGLDbaacqGH RaWkcaWGVbWaaeWaaeaadaWcaaqaaiaad2eadaahaaWcbeqaaiaaik daaaaakeaacaWGUbWaaWbaaSqabeaacaaIYaaaaaaaaOGaayjkaiaa wMcaaiaai6caaaaaaa@1252@

En combinant les termes, nous obtenons

V 2 ( θ ^ ) = c 2 p c 1 p c 2 V [ y ¯ c R Y ¯ c R ] V [ M ^ c R M c R ] + o ( M 2 n 2 ) . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaaI9aWaaabuaeqaleaacaWGJbaabeqdcqGHris5aOWaaSaaae aacaaIYaGaamiCamaaBaaaleaacaWGJbaabeaakiabgkHiTiaaigda aeaacaWGWbWaa0baaSqaaiaadogaaeaacaaIYaaaaaaakiaadAfada WadaqaaiqadMhagaqeamaaDaaaleaacaWGJbaabaGaamOuaaaakiab gkHiTiqadMfagaqeamaaDaaaleaacaWGJbaabaGaamOuaaaaaOGaay 5waiaaw2faaiaadAfadaWadaqaaiqad2eagaqcamaaDaaaleaacaWG JbaabaGaamOuaaaakiabgkHiTiaad2eadaqhaaWcbaGaam4yaaqaai aadkfaaaaakiaawUfacaGLDbaacqGHRaWkcaWGVbWaaeWaaeaadaWc aaqaaiaad2eadaahaaWcbeqaaiaaikdaaaaakeaacaWGUbWaaWbaaS qabeaacaaIYaaaaaaaaOGaayjkaiaawMcaaiaai6caaaa@5F9B@

Nous pouvons estimer p c MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiCamaaBa aaleaacaWGJbaabeaaaaa@3677@ par le taux de réponse empirique dans la poststrate c , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4yaiaacY caaaa@3606@ V [ y ¯ c R Y ¯ c R ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaadm aabaGabmyEayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaOGaeyOe I0IabmywayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaaGccaGLBb Gaayzxaaaaaa@3E20@ par s c 2 / n c R , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSGbaeaaca WGZbWaa0baaSqaaiaadogaaeaacaaIYaaaaaGcbaGaamOBamaaDaaa leaacaWGJbaabaGaamOuaaaaaaGccaGGSaaaaa@3AF0@ et, sous échantillonnage aléatoire simple, V [ M ^ c R M c R ] = M c p c ( M M c p c ) / n . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaadm aabaGabmytayaajaWaa0baaSqaaiaadogaaeaacaWGsbaaaOGaeyOe I0IaamytamaaDaaaleaacaWGJbaabaGaamOuaaaaaOGaay5waiaaw2 faaiaai2dadaWcgaqaaiaad2eadaWgaaWcbaGaam4yaaqabaGccaWG WbWaaSbaaSqaaiaadogaaeqaaOWaaeWaaeaacaWGnbGaeyOeI0Iaam ytamaaBaaaleaacaWGJbaabeaakiaadchadaWgaaWcbaGaam4yaaqa baaakiaawIcacaGLPaaaaeaacaWGUbaaaiaac6caaaa@4B98@ Le terme V 2 ( θ ^ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIYaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL Paaaaaa@398A@ peut être négatif quand p c < 1 / 2 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiCamaaBa aaleaacaWGJbaabeaakiaaiYdadaWcgaqaaiaaigdaaeaacaaIYaaa aaaa@38D4@ pour certaines poststrates; toutefois, quand p c < 1 / 2 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiCamaaBa aaleaacaWGJbaabeaakiaaiYdadaWcgaqaaiaaigdaaeaacaaIYaaa aaaa@38D4@ et V [ y ¯ c R ] > 0 , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaadm aabaGabmyEayaaraWaa0baaSqaaiaadogaaeaacaWGsbaaaaGccaGL BbGaayzxaaGaaGOpaiaaicdacaGGSaaaaa@3C79@ alors le terme d’ordre un de la variance, V 1 ( θ ^ ) , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaaBa aaleaacaaIXaaabeaakmaabmaabaGafqiUdeNbaKaaaiaawIcacaGL PaaacaGGSaaaaa@3A39@ est positif et le terme d’ordre deux est d’ordre inférieur.

Preuve du théorème 4. La condition (A4) assure que, asymptotiquement, une séparation complète n’aura pas lieu et que R h i k M MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOuamaaDa aaleaacaWGObGaamyAaiaadUgaaeaacaWGnbaaaaaa@390F@ est strictement non nul.

La dérivée de A ^ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabCyqayaaja aaaa@3548@ par rapport aux paramètres est

D ^ ( r , β , θ ) = A ^ ( β , θ ) = [ h i k S w h i k [ 1 + exp ( x h i k β ) ] 2 exp ( x h i k β ) x h i k x h i k 0 h i k S w h i k r h i k y h i k exp ( x h i k β ) x h i k 1 ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiqahseagaqcamaabmaabaGaaCOCaiaaiYcacaWHYoGaaGilaiab eI7aXbGaayjkaiaawMcaaaqaaiaai2dadaWcaaqaaiabgkGi2kqahg eagaqcaaqaaiabgkGi2oaabmaabaGaaCOSdiaaiYcacqaH4oqCaiaa wIcacaGLPaaadaahaaWcbeqaaOGamai2gkdiIcaaaaaabaaabaGaaG ypamaadmaabaqbaeqabiGaaaqaaiabgkHiTmaaqafabaGaam4Damaa BaaaleaacaWGObGaamyAaiaadUgaaeqaaaqaaiaadIgacaWGPbGaam 4AaiabgIGiolaadofaaeqaniabggHiLdGcdaWadaqaaiaaigdacqGH RaWkciGGLbGaaiiEaiaacchadaqadaqaaiabgkHiTiaahIhadaqhaa WcbaGaamiAaiaadMgacaWGRbaabaGcdaahaaadbeqaaKqzGfGamai2 gkdiIcaaaaGccaWHYoaacaGLOaGaayzkaaaacaGLBbGaayzxaaWaaW baaSqabeaacqGHsislcaaIYaaaaOGaciyzaiaacIhacaGGWbWaaeWa aeaacqGHsislcaWH4bWaa0baaSqaaiaadIgacaWGPbGaam4AaaqaaO WaaWbaaWqabeaajugybiadaITHYaIOaaaaaOGaaCOSdaGaayjkaiaa wMcaaiaahIhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaahI hadaqhaaWcbaGaamiAaiaadMgacaWGRbaabaGcdaahaaadbeqaaKqz GfGamai2gkdiIcaaaaaakeaacaWHWaaabaGaeyOeI0Yaaabuaeqale aacaWGObGaamyAaiaadUgacqGHiiIZcaWGtbaabeqdcqGHris5aOGa am4DamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaamOCamaaBa aaleaacaWGObGaamyAaiaadUgaaeqaaOGaamyEamaaBaaaleaacaWG ObGaamyAaiaadUgaaeqaaOGaciyzaiaacIhacaGGWbWaaeWaaeaacq GHsislcaWH4bWaa0baaSqaaiaadIgacaWGPbGaam4AaaqaaOWaaWba aWqabeaajugybiadaITHYaIOaaaaaOGaaCOSdaGaayjkaiaawMcaai aahIhadaqhaaWcbaGaamiAaiaadMgacaWGRbaabaGcdaahaaadbeqa aKqzGfGamai2gkdiIcaaaaaakeaacqGHsislcaaIXaaaaaGaay5wai aaw2faaiaai6caaaaaaa@B3F5@

En utilisant le conditionnement successif et l’indépendance de r MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaCOCaaaa@3569@ et Z , MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaCOwaiaacY caaaa@3601@ la valeur espérée de D ^ ( r , β , θ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabCirayaaja WaaeWaaeaacaWHYbGaaGilaiaahk7acaaISaGaeqiUdehacaGLOaGa ayzkaaaaaa@3C2F@ est

D ( R , β , θ ) = [ h i k U [ 1 + exp ( x h i k β ) ] 2 exp ( x h i k β ) x h i k x h i k 0 h i k U R h i k y h i k exp ( x h i k β ) x h i k 1 ] = [ X [ I + Q ] 2 Q X 0 T Q X 1 ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaahseadaqadaqaaiaahkfacaaISaGaaCOSdiaaiYcacqaH4oqC aiaawIcacaGLPaaaaeaacaaI9aWaamWaaeaafaqabeGacaaabaGaey OeI0YaaabuaeqaleaacaWGObGaamyAaiaadUgacqGHiiIZcaWGvbaa beqdcqGHris5aOWaamWaaeaacaaIXaGaey4kaSIaciyzaiaacIhaca GGWbWaaeWaaeaacqGHsislcaWH4bWaa0baaSqaaiaadIgacaWGPbGa am4AaaqaaOWaaWbaaWqabeaajugybiadaITHYaIOaaaaaOGaaCOSda GaayjkaiaawMcaaaGaay5waiaaw2faamaaCaaaleqabaGaeyOeI0Ia aGOmaaaakiGacwgacaGG4bGaaiiCamaabmaabaGaeyOeI0IaaCiEam aaDaaaleaacaWGObGaamyAaiaadUgaaeaakmaaCaaameqabaqcLbwa cWaGyBOmGikaaaaakiaahk7aaiaawIcacaGLPaaacaWH4bWaaSbaaS qaaiaadIgacaWGPbGaam4AaaqabaGccaWH4bWaa0baaSqaaiaadIga caWGPbGaam4AaaqaaOWaaWbaaWqabeaajugybiadaITHYaIOaaaaaa GcbaGaaCimaaqaaiabgkHiTmaaqafabeWcbaGaamiAaiaadMgacaWG RbGaeyicI4Saamyvaaqab0GaeyyeIuoakiaadkfadaWgaaWcbaGaam iAaiaadMgacaWGRbaabeaakiaadMhadaWgaaWcbaGaamiAaiaadMga caWGRbaabeaakiGacwgacaGG4bGaaiiCamaabmaabaGaeyOeI0IaaC iEamaaDaaaleaacaWGObGaamyAaiaadUgaaeaakmaaCaaameqabaqc LbwacWaGyBOmGikaaaaakiaahk7aaiaawIcacaGLPaaacaWH4bWaa0 baaSqaaiaadIgacaWGPbGaam4AaaqaaOWaaWbaaWqabeaajugybiad aITHYaIOaaaaaaGcbaGaeyOeI0IaaGymaaaaaiaawUfacaGLDbaaae aaaeaacaaI9aWaamWaaeaafaqabeGacaaabaGaeyOeI0IabCiwayaa faWaamWaaeaacaWHjbGaey4kaSIaaCyuaaGaay5waiaaw2faamaaCa aaleqabaGaeyOeI0IaaGOmaaaakiaahgfacaWHybaabaGaaCimaaqa aiabgkHiTiqahsfagaqbaiaahgfacaWHybaabaGaeyOeI0IaaGymaa aaaiaawUfacaGLDbaacaaIUaaaaaaa@B1AE@

Aussi, Cov [ vec D ^ ( r , β , θ ) ] = O ( M 2 / n ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaae4qaiaab+ gacaqG2bWaamWaaeaacaqG2bGaaeyzaiaabogaceWHebGbaKaadaqa daqaaiaahkhacaaISaGaaCOSdiaaiYcacqaH4oqCaiaawIcacaGLPa aaaiaawUfacaGLDbaacaaI9aGaam4tamaabmaabaWaaSGbaeaacaWG nbWaaWbaaSqabeaacaaIYaaaaaGcbaGaamOBaaaaaiaawIcacaGLPa aaaaa@498B@ parce que

V [ h i k S w h i k r h i k y h i k exp ( x h i k β ) x h i k ] = V [ h i k S w h i k R h i k y h i k exp ( x h i k β ) x h i k ] + E { V [ h i k S w h i k r h i k y h i k exp ( x h i k β ) x h i k | Z ] } . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqbaeaabiGaaa qaaiaadAfadaWadaqaamaaqafabeWcbaGaamiAaiaadMgacaWGRbGa eyicI4Saam4uaaqab0GaeyyeIuoakiaadEhadaWgaaWcbaGaamiAai aadMgacaWGRbaabeaakiaadkhadaWgaaWcbaGaamiAaiaadMgacaWG RbaabeaakiaadMhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaaki GacwgacaGG4bGaaiiCamaabmaabaGaeyOeI0IaaCiEamaaDaaaleaa caWGObGaamyAaiaadUgaaeaakmaaCaaameqabaqcLbwacWaGyBOmGi kaaaaakiaahk7aaiaawIcacaGLPaaacaWH4bWaa0baaSqaaiaadIga caWGPbGaam4AaaqaaOWaaWbaaWqabeaajugybiadaITHYaIOaaaaaa GccaGLBbGaayzxaaaabaGaaGypaiaadAfadaWadaqaamaaqafabeWc baGaamiAaiaadMgacaWGRbGaeyicI4Saam4uaaqab0GaeyyeIuoaki aadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadkfadaWg aaWcbaGaamiAaiaadMgacaWGRbaabeaakiaadMhadaWgaaWcbaGaam iAaiaadMgacaWGRbaabeaakiGacwgacaGG4bGaaiiCamaabmaabaGa eyOeI0IaaCiEamaaDaaaleaacaWGObGaamyAaiaadUgaaeaakmaaCa aameqabaqcLbwacWaGyBOmGikaaaaakiaahk7aaiaawIcacaGLPaaa caWH4bWaa0baaSqaaiaadIgacaWGPbGaam4AaaqaaOWaaWbaaWqabe aajugybiadaITHYaIOaaaaaaGccaGLBbGaayzxaaaabaaabaGaaGzb VlabgUcaRiaadweadaGadaqaaiaadAfadaWadaqaamaaeiaabaWaaa buaeqaleaacaWGObGaamyAaiaadUgacqGHiiIZcaWGtbaabeqdcqGH ris5aOGaam4DamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaam OCamaaBaaaleaacaWGObGaamyAaiaadUgaaeqaaOGaamyEamaaBaaa leaacaWGObGaamyAaiaadUgaaeqaaOGaciyzaiaacIhacaGGWbWaae WaaeaacqGHsislcaWH4bWaa0baaSqaaiaadIgacaWGPbGaam4Aaaqa aOWaaWbaaWqabeaajugybiadaITHYaIOaaaaaOGaaCOSdaGaayjkai aawMcaaiaahIhadaqhaaWcbaGaamiAaiaadMgacaWGRbaabaGcdaah aaadbeqaaKqzGfGamai2gkdiIcaaaaaakiaawIa7aiaahQfaaiaawU facaGLDbaaaiaawUhacaGL9baacaaIUaaaaiaaiccaaaa@C3D4@

Le premier terme est O ( M 2 / n ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4tamaabm aabaWaaSGbaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaGcbaGaamOB aaaaaiaawIcacaGLPaaaaaa@3999@ en vertu des arguments classiques et le deuxième terme est O ( M 2 / n ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4tamaabm aabaWaaSGbaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaGcbaGaamOB aaaaaiaawIcacaGLPaaaaaa@3999@ en vertu du lemme 1, en notant que le bornage de R h i k MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOuamaaBa aaleaacaWGObGaamyAaiaadUgaaeqaaaaa@383C@ et x h i k MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaCiEamaaBa aaleaacaWGObGaamyAaiaadUgaaeqaaaaa@3866@ borne également exp ( x h i k β ) . MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciyzaiaacI hacaGGWbWaaeWaaeaacqGHsislcaWH4bWaa0baaSqaaiaadIgacaWG PbGaam4AaaqaaOWaaWbaaWqabeaajugybiadaITHYaIOaaaaaOGaaC OSdaGaayjkaiaawMcaaiaac6caaaa@4399@ Par conséquent,

V [ β ^ β θ ^ θ ] = D ( R , β , θ ) 1 V [ h i k S w h i k u ( y h i k , x h i k , r h i k , β ) ] D ( R , β , θ ) T + o ( M 2 / n ) . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOvamaadm aabaqbaeqabiqaaaqaaiqahk7agaqcaiabgkHiTiaahk7aaeaacuaH 4oqCgaqcaiabgkHiTiabeI7aXbaaaiaawUfacaGLDbaacaaI9aGaaC iramaabmaabaGaaCOuaiaaiYcacaWHYoGaaGilaiabeI7aXbGaayjk aiaawMcaamaaCaaaleqabaGaeyOeI0IaaGymaaaakiaadAfadaWada qaamaaqafabeWcbaGaamiAaiaadMgacaWGRbGaeyicI4Saam4uaaqa b0GaeyyeIuoakiaadEhadaWgaaWcbaGaamiAaiaadMgacaWGRbaabe aakiaahwhadaqadaqaaiaadMhadaWgaaWcbaGaamiAaiaadMgacaWG RbaabeaakiaaiYcacaWH4bWaaSbaaSqaaiaadIgacaWGPbGaam4Aaa qabaGccaaISaGaamOCamaaBaaaleaacaWGObGaamyAaiaadUgaaeqa aOGaaGilaiaahk7aaiaawIcacaGLPaaaaiaawUfacaGLDbaacaWHeb WaaeWaaeaacaWHsbGaaGilaiaahk7acaaISaGaeqiUdehacaGLOaGa ayzkaaWaaWbaaSqabeaacqGHsislcaWGubaaaOGaey4kaSIaam4Bam aabmaabaWaaSGbaeaacaWGnbWaaWbaaSqabeaacaaIYaaaaaGcbaGa amOBaaaaaiaawIcacaGLPaaacaaIUaaaaa@79D2@

Le résultat en (3.3) s’ensuit parce que

[ D ( R , β , θ ) ] 1 = [ C 0 T Q X C 1 ] . MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiFu0Je9sqqrpepC0xbbL8F4rqqr=fFD0xd9Wqpe0dd9 qqaqFeFr0xbbG8FaYPYRWFb9fi0lXxbvc9Ff0dfrpm0dXdHqps0=vr 0=vr0=fdbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaaca WHebWaaeWaaeaacaWHsbGaaGilaiaahk7acaaISaGaeqiUdehacaGL OaGaayzkaaaacaGLBbGaayzxaaWaaWbaaSqabeaacqGHsislcaaIXa aaaOGaaGypamaadmaabaqbaeqabiGaaaqaaiabgkHiTiaahoeaaeaa caWHWaaabaGabCivayaafaGaaCyuaiaahIfacaWHdbaabaGaeyOeI0 IaaGymaaaaaiaawUfacaGLDbaacaaIUaaaaa@4ADA@

Bibliographie

Abraham, K.G., Helms, S. et Presser, S. (2009). How social processes distort measurement: The impact of survey nonresponse on estimates of volunteer work in the United States. American Journal of Sociology, 114(4), 1129-1165.

Baker, R., Brick, J.M., Bates, N.A., Battaglia, M., Couper, M.P., Dever, J.A., Gile, K.J. et Tourangeau, R. (2013). Summary report of the AAPOR task force on nonprobability sampling. Journal of Survey Statistics and Methodology, 1, 90-143.

Binder, D.A. (1983). On the variances of asymptotically normal estimators from complex surveys. International Statistical Review/Revue Internationale de Statistique, 51, 279-292.

Brick, J.M. (2013). Unit nonresponse and weighting adjustments: A critical review. Journal of Official Statistics, 29(3), 329-353.

Eltinge, J.L. (2002). Diagnostics for the practical effects of nonresponse adjustment methods. Dans Survey Nonresponse, (Éds., R.M. Groves, D.A. Dillman, J.L. Eltinge et R.J.A. Little), New York: John Wiley & Sons, Inc., 431-443.

Fay, R.E. (1991). A design-based perspective on missing data variance. Dans Proceedings of the 1991 Annual Research Conference, U.S. Bureau of the Census, Washington, DC, 429-440.

Fuller, W.A. (2009). Sampling Statistics. Hoboken, NJ: Wiley.

Groves, R.M., et Heeringa, S.G. (2006). Responsive design for household surveys: Tools for actively controlling survey errors and costs. Journal of the Royal Statistical Society, Series A (Statistics in Society), 169(3), 439-457.

Groves, R.M. (2006). Nonresponse rates and nonresponse bias in household surveys. Public Opinion Quarterly, 70(5), 646-675.

Hamrick, K.S. (2012). Nonresponse Bias Analysis of Body Mass Index Data in the Eating and Health Module. Rapport technique 1934, United States Department of Agriculture Economic Research Service, Washington, DC.

Harris-Kojetin, B.A. (2012). Nonresponse Bias Analysis for Establishment Surveys: Guidance from the U.S. Office of Management and Budget. Document présenté au DC-AAPOR, http://www.dc-aapor.org/documents/Harris-Kojetin2012.pdf.

Haziza, D., et Lesage, É. (2016). A discussion of weighting procedures for unit nonresponse. Journal of Official Statistics, 32(1), 129-145.

Haziza, D., Thompson, K.J. et Yung, W. (2010). L’effet des ajustements pour la non-réponse sur l’estimation de la variance. Techniques d’enquête, 36, 1, 39-48. Article accessible à l'adresse http://www.statcan.gc.ca/pub/12-001-x/2010001/article/11246-fra.pdf.

Kim, J.K., et Kim, J.J. (2007). Nonresponse weighting adjustment using estimated response probability. Canadian Journal of Statistics, 35(4), 501-514.

Kohut, A., Keeter, S., Doherty, C., Dimock, M. et Christian, L. (2012). Assessing the Representativeness of Public Opinion Surveys. Pew Research Center, Washington, DC.

Lohr, S.L., Hsu, V. et Montaquila, J. (2015). Using classification and regression trees to model survey nonresponse. Proceedings of the Survey Research Methods Section, American Statistical Association, 2071-2085.

Oh, H.L., et Scheuren, F.J. (1987). Weighting adjustments for unit nonresponse. Dans Incomplete Data in Sample Surveys, (Éds., W.G. Madow, I. Olkin et D.B. Rubin), New York: Academic Press, 2, 143-184.

Riddles, M., Marker, D.A., Rizzo, L., Wiley, E. et Zukerberg, A. (2015). Adaptive Design for the National Teacher Principal Survey. Document présenté à l’AAPOR 70th Annual Conference, Hollywood, FL.

R Core Team (2015). R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienne, Autriche.

Särndal, C.-E., et Lundström, S. (2005). Estimation in Surveys with Nonresponse. Hoboken, NJ: Wiley.

SAS Institute, Inc. (2011). SAS/STAT 9.3 User’s Guide. Cary, NC: SAS Institute, Inc.

Shao, J., et Steel, P. (1999). Variance estimation for survey data with composite imputation and nonnegligible sampling fractions. Journal of the American Statistical Association, 93, 254-265.

Shao, J., et Tu, D. (1995). The Jackknife and Bootstrap. New York: Springer.

Tourangeau, R., Brick, J.M., Lohr, S. et Li, J. (2016). Adaptive and responsive survey designs: A review and assessment. Journal of the Royal Statistical Society, Series A (Statistics in Society), publié en ligne, http://onlinelibrary.wiley.com/doi/10.1111/rssa.12186/pdf.

United States Office of Management and Budget (2006). Standards and guidelines for statistical surveys. https://www.whitehouse.gov/sites/default/files/omb/inforeg/statpolicy/standards_stat_surveys.pdf.

Yung, W., et Rao, J.N.K. (2000). Jackknife variance estimation under imputation for estimators using poststratification information. Journal of the American Statistical Association, 95(451), 903-915.

Date de modification :