# **3. Experimental Design**

This study took place in Hayabley, a poor neighborhood of urban Djibouti City. Households were eligible to participate in the study if they had either a pregnant woman and/or a mother of children younger than 2 years old who was registered for and participating in nutrition sessions. Of the 1,055 eligible households, 1,011 (96 percent) were successfully interviewed and enrolled in the study at baseline.<sup>6</sup> Our evaluation exploited the phased rollout of Djibouti’s public works program. After participating in the baseline survey, each of the 1,011 eligible households were randomly assigned to one of 4 groups (A-D, as shown in Figure 1), and offered the opportunity to engage in public works every 6 months, starting in 2014 and ending in 2016. A total of 504 households constituted the first two randomly allocated groups, A and B, which were given priority in the opportunity to work. These two groups were designated as the treatment group. The remaining 507 households, groups C and D, constituted the control group and started the public works, on average, 15 months later than groups A and B (and nine months after the intervention for the treatment group ended). Stratification was conducted by the location of the public works (5 project sites);<sup>7</sup> by nutrition session type: one session for pregnant women, and another for women with child(ren) aged 0-2 years; by the session participant subsets: women in ongoing nutrition sessions and those whose sessions had ended, and by session groups. This stratification results in 65 strata.<sup>8</sup> There are two potential threats to the validity of this study. First, the gradual rollout of the intervention might have generated anticipation effects insofar as women who were not offered to participate in the program in the first round knew that they would eventually receive the offer. By midline most women in the control households (93 percent) who had yet to be offered the opportunity to work already knew about the program. As a result, these women might have delayed involvement in self-employment activities while waiting for the public works offer. However, since the women’s baseline level of economic engagement was very low, the margin for the aforementioned effect is likely small. Still, anticipation effects could have manifested in other ways; for example, some participants could have sought credit to engage in advanced spending with the expectation of receiving future public works income.

> 6 One-third of the 44 non-responses is due to the fact that no one from the household was present/available at time of the recruitment, while another one-third of the non-responses is due to refusal to be interviewed. 7 For program implementation, Hayabley district was divided into five geographical areas, and women were required to participate in the nutrition sessions offered where they lived.

> 8 Within our analysis we control for strata. Due to the high total sample and the large number of strata, 8 of the 65 strata cells have only one study participant after stratification. We dropped these observations from our analysis due to the lack of variation within the strata. We conduct robustness checks of main results using more aggregate strata variables (i.e., location, session type, and current status), which results in 20 strata categories instead of 65. Results are unchanged (Annex B Table 1).

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