- Introduction
- Introduction to Correspondence Tables
- Developing the NOC 2016 – SOC 2018 (US) correspondence table
Introduction
This reference note provides a brief introduction and reference for the Statistics Canada correspondence table between the Canadian National Occupational Classification (NOC) 2016 Version 1.3 and the American Standard Occupational Classification (SOC 2018) (US).
In general, correspondence tables are used in classification-related work to summarize the theoretical relationships between different classification systems.
National Occupational Classification (NOC) 2016 Version 1.3
The NOC has been developed and maintained as part of a collaborative partnership between Employment and Social Development Canada (ESDC) and Statistics Canada. The NOC is designed to classify occupational information from statistical surveys. It is also used in a range of contexts to compile, analyze and communicate information about occupations. Occupational information is of critical importance for the provision of labour market and career intelligence, skills development, occupational forecasting, labour supply and demand analysis, employment equity and numerous other programs and services.
The structure and format of the National Occupational Classification 2016 is based on a four-tiered hierarchical arrangement of occupational groups with successive levels of disaggregation, with broad occupational categories at the lowest level and unit groups at the highest level of disaggregation. There are 500 unit groups in the NOC 2016, with approximately 35,000 example job titles. Some titles are clearly occupations, such as librarian and chef, while others represent a range of jobs, such as furniture assembler and sawmill machine operator. These titles are used to describe the work performed by many individuals holding similar jobs within an occupational area. The list of titles in the NOC is not meant to be exhaustive, but attempts to cover the most commonly used and universally understood labels that identify work in the labour market.
More information on the NOC is available here: National Occupational Classification (NOC) 2016 Version 1.3.
Standard Occupational Classification (SOC) 2018 (US)
The Standard Occupational Classification system is used by the United States' federal agencies to classify workers and jobs into occupational categories for the purpose of collecting, calculating, analyzing or disseminating data. The most recent version used for this correspondence table is the SOC 2018 (US).
To facilitate classification and presentation of data, the SOC is organized into a tiered system with four levels, ranging from major groups to detailed occupations. There are, at the lowest level of specification, 867 detailed occupations. Detailed occupations with similar job duties, and in some cases, similar skills, education, and/or training, are grouped together in the SOC. Each worker is classified into only one of the 867 detailed occupations based on the tasks performed. The SOC, like the NOC, does not attempt to provide an exhaustive list of job titles, but attempts to cover the most commonly used and universally understood labels that identify work in the US labour market.
More information on the SOC is available here: Standard Occupational Classification (SOC) 2018 (US).
Introduction to Correspondence Tables
Correspondence tables are used in classification-related work to summarize the relationships between different classification systems. These tables relate the individual detailed classification items (e.g. classes) of the different systems, as well as the more aggregate (or "roll-up") levels of each system. Correspondence tables are also known as concordances, crosswalks, mappings, link tables or look-up tables.
In correspondence tables, the source (or object) classification is on the left-hand side of the table, while the target classification is on the right-hand side. Correspondence tables should be developed starting from the lowest level categories. Then, high-level links can be derived from the lower ones.
When building correspondence tables, various scenarios may be encountered. Classification items may match perfectly across classifications (one-to-one), or one classification item in the object classification may split into several classification items in the target classification (one-to-many); in other cases, two or more classification items in the object classification may link to one (many-to-one) or many classification items (many-to-many) in the target classification.
Types of correspondence tables
There are two main types of correspondence tables: Definitional and Empirical.
- Definitional Correspondence Tables: These tables show relationships based on the definitions of the classification items subject to the correspondence process. For a given object class, all target classification items are identified that are wholly or partly synonymous. This is assessed by comparing the definitions and illustrative examples provided for each classification item, taking into account their full scope. Each example and each element of the definition must be assessed. This is sometimes referred to as working from the "granular level". Definitional correspondence tables are also referred to as classification correspondence tables, conceptual correspondence tables or theoretical correspondence tables. This is the type of correspondence table mainly developed for the purpose of standardization at Statistics Canada.
- Empirical Correspondence Tables: These tables are also developed to establish relationships between classification items of two classification systems. They can be used to measure the significance of each of the links, based on actual data. They are also good tools to manage the one-to-many and many-to-many splits. They are usually a means of selecting key relationships when developing forced one-to-one correspondences. Empirical correspondences might also be referred to as statistical correspondence tables, though a definitional correspondence table can still be used for statistical purposes as well.
Uses of Correspondence Tables
Correspondence tables allow users to see the relationships between the classification items of the two systems. They are a convenient summary of the similarities and differences between two classifications.
Correspondence Tables Terms and Structure
Object Classification: The user is mapping from this classification. The object classification is the starting point. In the NOC to SOC correspondence table, NOC 2016 is considered as the object classification as the respective NOC classes are mapped to the SOC.
Target Classification: The user is mapping to this classification. In the NOC to SOC correspondence table, SOC 2018 (US) is considered as the target classification as all SOC classes, which are synonymous (partially or fully) with each NOC class, are identified.
Structure: Correspondence tables are typically presented with the object class on the left-hand side and the target class on the right.
Classification item: A classification item represents a category at a certain level within a statistical classification. It defines the content and the borders of the category. An object/unit can be classified to one and only one classification item at each level of a statistical classification.
Asterisk: An asterisk (*) is used to flag situations in which a single object classification item (left side of the correspondence table) corresponds to two or more target classification items (right side of the correspondence table). It is referred to as a "partial" flag.
Explanatory Notes: An explanatory note provides a short description of the nature of the overlap between the object and target classification item(s). It is required for many to one relationships as well as when the "partial" flag is used.
Good practice guidelines used when building this NOC to SOC Correspondence Table
- All detailed classification items of both the object and target classifications must be present (100% mapped)
- All relationships between those classification items must be known by (or summarized for) the correspondence table builder.
- The names of all classification items must be available to the correspondence table builder.
- For classifications with aggregate (or "roll-up") levels for which the numeric coding system involves removing the final digit from the more detailed codes, and doing so successively for each level of aggregation, higher levels are straightforward. For classifications that are not hierarchical in this way, the aggregation structure must be explicitly available to the correspondence table builder.
Examples of elements of correspondence tables
This section provides four examples from the NOC – SOC correspondence table to demonstrate how to read the correspondence table. The first example shows a one-to-one relationship, the second example shows a one-to-many relationship, the third example shows a many-to-one relationship and the fourth example shows a many-to-many links with tables for both sides for illustration.
The correspondence examples are shown at the lowest level of both classifications, namely at the 4-digit level in NOC and the 6-digit level in SOC. The relationships between the two classifications can be simple or complex, with example 4 being one of the complex ones.
Example 1 - one-to-one relationship
In this example, a NOC classification item maps to one SOC classification item, their coverage of occupations being the same. All of the occupational duties in NOC 2234 are found in SOC 13-1051. This is a one-to-one relationship and therefore no explanatory note is required, and also, no asterisk is needed in the column "partial".
| NOC 2016 Version 1.3 | Partial | SOC 2018 (US) | * Explanatory notes |
|---|---|---|---|
| 2234 Construction Estimators | 13-1051 Construction Estimators |
Example 2 - One-to-many relationship
In this example, a NOC classification item maps to more than one SOC classification item. Each SOC item represents a part of the NOC item. This is a one-to-many relationship and therefore requires an asterisk (indicating a partial match) and an explanatory note to detail how the NOC classification item relates to each SOC classification item.
| NOC 2016 Version 1.3 | Partial | SOC 2018 (US) | * Explanatory notes |
|---|---|---|---|
| 1123 Professional occupations in advertising, marketing and public relations | * | 13-1011 Agents and Business Managers of Artists, Performers, and Athletes | Only agents, publicists, promoters, representatives and managers of performers, athletes, writers and other talented individuals |
| 1123 Professional occupations in advertising, marketing and public relations | * | 13-1131 Fundraisers | Only professionals specializing in fundraising |
| 1123 Professional occupations in advertising, marketing and public relations | * | 13-1161 Market Research Analysts and Marketing Specialists | Only professionals specializing in marketing, including advertising specialists and consultants |
| 1123 Professional occupations in advertising, marketing and public relations | * | 27-3031 Public Relations Specialists | Only professionals specializing in communication, media and public relations and publicity |
| 1123 Professional occupations in advertising, marketing and public relations | * | 41-3011 Advertising Sales Agents | Only professionals specializing in advertising accounts management |
The asterisk (*) is used to indicate that each classification item of the target classification (SOC 2018 (US)) represents a portion of the classification item of the object classification (NOC). In this example above, the occupations represented in NOC code 1123 are split between 5 classification items of the SOC 2018 (US); which means these 5 SOC categories are merged into one NOC category.
The explanatory note provides a short description of the nature of the link between the NOC and SOC classification items. It is important to note that occupational example titles may vary from one classification to the other. As a result, in the example 2 table, all titles related to each SOC category (e.g., 27-3031 for professionals specializing in communication, media and public relations and publicity), are also occupations included in 27-3031 and therefore are linked to that SOC code which is linked to NOC code 1123.
Example 3 – Many-to-one relationship
In this example, two or more NOC classification items map to one SOC classification item. An explanatory note is required to detail how the different NOC classification items relate to the SOC classification item.
| NOC 2016 Version 1.3 | Partial | SOC 2018 (US) | * Explanatory notes |
|---|---|---|---|
| 2143 Mining Engineers | 17-2151 Mining and Geological Engineers, Including Mining Safety Engineers | Only mining engineers | |
| 2144 Geological Engineers | 17-2151 Mining and Geological Engineers, Including Mining Safety Engineers | Only geological engineers | |
| 7313 Heating, refrigeration and air conditioning mechanics | 49-9021 Heating, Air Conditioning, and Refrigeration Mechanics and Installers | Only mechanics and installers for heating, refrigeration and air conditioning | |
| 7331 Oil and solid fuel heating mechanics | 49-9021 Heating, Air Conditioning, and Refrigeration Mechanics and Installers | Only mechanics and installers for oil and solid fuel heating |
The explanatory note provides a short description of the nature of the link between the NOC and SOC classification items. It is important to note that occupational example titles may vary from one classification to the other. As a result, in example 3 table, all related titles to these NOC classification items are also included in the links to that SOC code. The NOC to SOC correspondence is not mapped in this fashion. This example is provided to demonstrate many-to-one relationships within the NOC – SOC correspondence, and how it would be displayed, if sorted in this manner.
Example 4 – Many-to-many relationship
In this example, two or more NOC classification items map to many (two or more) SOC classification items, and vice versa. An explanatory note is required to detail how the different NOC classification items relate to the SOC classification items. The two tables below illustrate many-to-many relationships between NOC and SOC. We use SOC code 11-9111 to illustrate the many-to-many relationships showing that it is linked to 4 NOC codes (0014, 0114, 0311 and 0632), which in turn are linked to other SOC codes. Further, each individual SOC 2018 (US) code listed in the second table below could also be linked to different NOC 2016 codes than those shown on that table. One case to notice is the NOC 0311 which is only linked to SOC code 11-9111 therefore no asterisk is used in the second table below. In fact, the asterisk is not used in that case because the object classification is the one driving the use of partials; therefore, the asterisk is used on the reverse correspondence table (SOC 2018 (US) to NOC 2016).
| SOC 2018 (US) | Partial | NOC 2016 Version 1.3 | * Explanatory notes |
|---|---|---|---|
| 11-9111 - Medical and Health Services Managers | * | 0014 Senior managers - health, education, social and community services and membership organizations | Only administrators and executive directors of hospitals |
| 11-9111 - Medical and Health Services Managers | * | 0114 Other administrative services managers | Only administrators, managers and directors in medical and health records management, including patient-registration manager and hospital admissions director |
| 11-9111 - Medical and Health Services Managers | * | 0311 Managers in health care | Only managers in health care not already represented in other relationships between this SOC code and NOC |
| 11-9111 - Medical and Health Services Managers | * | 0632 Accommodation service managers | Only managers of nursing homes |
| NOC 2016 Version 1.3 | Partial | SOC 2018 (US) | * Explanatory notes |
|---|---|---|---|
| 0014 Senior managers - health, education, social and community services and membership organizations | * | 11-9111 - Medical and Health Services Managers | Only administrators and executive directors of hospitals |
| 0014 Senior managers - health, education, social and community services and membership organizations | * | 11-1011 - Chief Executives | Only highest level management positions |
| 0014 Senior managers - health, education, social and community services and membership organizations | * | 11-1021 - General and Operations Managers | Only general and operations managers as specified in this NOC |
| 0114 Other administrative services managers | * | 11-9111 - Medical and Health Services Managers | Only administrators, managers and directors in medical and health records management, including patient-registration manager and hospital admissions director |
| 0114 Other administrative services managers | * | 11-3012 - Administrative Services Managers | Only administrative services managers, excluding administrators, managers and directors in medical and health records management, and also excluding patient-registration manager and hospital admissions director |
| 0311 Managers in health care | 11-9111 - Medical and Health Services Managers | ||
| 0632 Accommodation service managers | * | 11-9072 - Entertainment and Recreation Managers, Except Gambling | Only managers of ski resorts |
| 0632 Accommodation service managers | * | 11-9081 - Lodging Managers | Only accommodation and lodging service managers |
| 0632 Accommodation service managers | * | 11-9111 - Medical and Health Services Managers | Only managers of nursing homes |
| 0632 Accommodation service managers | * | 39-9041 - Residential Advisors | Only managers of student residences |
Developing the NOC 2016 – SOC 2018 (US) correspondence table
The correspondence table between NOC 2016 and SOC 2018 (US) relates the individual detailed classification items of the two systems – notably leading statements, main duties (job descriptions) and occupational qualifications and requirements, which in turn informs mappings of occupational title examples. For this correspondence table, analysis of occupations was completed for NOC 2016 at the 4 digit level (the lowest level and detailed description level), for SOC 2018 (US) at the 6 digit level (lowest level with occupation leading statements) and at the O*NET-SOC 8 digit detailed descriptions level Footnote 1. In addition, the crosswalk O*NET-SOC 2010 to SOC 2018 (US) was used to link the O*Net to SOC 2010 with the SOC 2018 (US).
Key considerations when using the NOC 2016 –SOC 2018 (US) correspondence table:
- The NOC 2016 –SOC 2018 (US) correspondence table is definitional and based on theoretical links.
- Each national occupational classification, NOC and SOC, structure encompasses the whole occupational universe for that country.
- Each national occupational classification provides a non-exhaustive list of occupational example titles at the lowest aggregate level.
- Occupational examples titles vary from one country's occupational classification to another.
- To aid in creating this correspondence table, the scope or function of an occupation was used to determine the relationship.
- In keeping with good practice and broader usage, there is a 100% mapping between the two classifications at the lowest level for each of their classification items.