modules in LSMS‐ISA surveys include a variant of the question _‘In the last [reference period], did you work as an employee for a wage, salary, commission, or any payment in kind, including doing paid apprenticeship, domestic work or paid farm work, even if only for one hour?’_ This question is a critical first step to capture wage employment, including casual labor. The complexity becomes, however, evident in those surveys that aim to distinguish casual labor from other types of wage employment. The 2015/16 Ethiopia LSMS‐ISA survey, for instance, includes the questions _‘How many hours in the last seven days did [name] do any work for a wage, salary, commission, or any payment in kind, excluding temporary?’_ and _‘How many hours in the last seven days did [name] engage in casual, part‐time, or temporary labor?’_ The difference between both questions is unclear and is not further clarified in the enumerator manual. A similar approach is used in Malawi, where the first question is the same as in Ethiopia but excludes ‘ganyu’ labor<sup>15</sup> , while the second question asks the respondents to report on casual, part‐time or _ganyu_ labor. In Tanzania, a different approach is followed. Rather than distinguishing casual labor from other types of wage employment using stylized questions, persons engaged in wage employment are asked whether they have a ‘permanent’, a ‘specific task’, a ‘fixed time’ or a ‘casual contract’. In the Swahili questionnaire, the term casual contract is translated as ‘kibarua’. According to Oya (2013) and Mueller (2015), _kibarua_ is used for most forms of manual casual labor, and often has a negative connotation in Tanzania.

# 4.2.4. Time diaries

The fourth approach to measure hours worked in paid and unpaid economic activities is a time diary, an approach that was initially developed to measure time use within a reference period (typically the last 24 hours) but can also be used to identify productive activities. Time diaries have several advantages. First, time diaries are more accurate and suffer less from recall bias than stylized questions (Bonke, 2005; Kan & Pudney, 2008). Second, they provide an exhaustive list of all activities undertaken in the last 24 hours (Seymour et al., 2017). Third, given the format of a time diary, enumerators can easily verify that the sum of all activities equals 24 hours, which may reduce measurement error. Fourth, they offer the potential to capture simultaneous activities (for example, women caring for children and working on an agricultural plot at the same time) (Grosh & Glewwe, 2000; ILO, 2018e).

Time diaries increase, however, the complexity and duration on the interview, have high operational costs, and might yield inaccurate response due to respondents’ memory loss and illiteracy. The United Nations Statistics Division (UNSD) Time Use Data Portal<sup>16</sup> identified several methodological issues regarding collecting accurate time use data that are not yet settled such as (1) whether a time diary should be administered to all household member or only to (randomly) selected household members; (2) whether proxy‐reporting of time use is acceptable; (3) how to deal with variation in time use across the week (e.g. interviews on Tuesdays versus on Sundays) and (4) whether the definition of time is context and cultural

> 15 The enumerator manual defines _ganyu_ labor as _“short term labour hired on a daily or other short‐term basis. Most commonly, piecework weeding or ridging on the fields of other smallholders or on agricultural estates. However, ganyu labour can also be used for non‐agricultural tasks, such as construction and gardening.”_

> 16 https://unstats.un.org/unsd/gender/timeuse/ (last updated in May 2016)

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