- earnings from employment (standardized by a unit of time, such as hourly or monthly earnings).

While the conceptual meaning of these variables is pretty simple, development of standard definitions and measurement techniques has been the subject of substantial discussion and survey research in the post World War II period.). Because statistics are a system, the definitions of employment outcomes necessary connect with other parts of the national social and economic data systems, including the System of National Accounts (SNA). _Therefore, the SNA provides the conceptual framework for the measurement of time spent in employment (economic activity)._ The objective of collecting data on employment should include measurement all labor effort spent on the production measured in the SNA. With this objective in mind, discussions, mostly led by the ILO in their annual meetings of statisticians, have established specific, precise, and lengthy technical specifications for these terms (and associated modifiers) which are accepted by almost all national statistics offices.<sup>7</sup> Some of these definitions are even included in legal documents (e.g. the definition of selfemployment vs. employment by an employer for the purposes of tax policy or the eligibility for social security benefits).

Translating these widely accepted specifications into survey questions which are both easily administered, and understood by respondents in different cultural, social, and economic settings, is not easy. Commonly used words are rarely adequate. For example, what is “work” or a “job”? For a wage earner in an OECD country - someone who leaves home 5 days a week and goes to a factory or office for a usual number of hours each day or week and gets a regular income - the answer may be clear. A simple question in a survey such as “what is your main job?” will normally provoke from the respondent an answer regarding the _economic_ activity where she has spent the most time in the last week, month or year _and_ where the most labor income has been earned. The vast majority of the labor force in industrial countries does not change economic activities with the season, nor do they work in several sectors or take on multiple occupations during the year.

But the situation is much more complicated in low-income countries, where the most activities take place around or near the home, within a household economic system. Depending on the country, 30-50 percent of the economically active population reports undertaking two or more substantially different economic activities during the year (for example, agriculture during harvest time and running a kiosk the rest of the time), as well as doing household chores. The definition of employment is doing any _economic activity_ even for 1 hour. In order to answer the question “what is your main job?” respondents would have to know which of their daily, weekly, or monthly activities are classified as economic ones (and therefore could be called “work” or a “job”). To give some examples:

- Is running errands in an unpaid apprenticeship “work”?

- Is tending livestock or small farm animals ‘”work”?

- Is watering vegetables in a family garden “work”?

> an outcome variable.  It can be measured by low hours worked and job search. See ILO (1982) and subsequent resolutions on this topic. As ILO (2012) notes, problems remain with the international comparability of statistics on underemployment.

> 7 See ILO (1993) “Resolution Concerning the International Classification of Status in Employment (ICSE), Adopted by the Fifteenth International Conference of Labour Statisticians”.

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