tions that regress an indicator for responding to a post-displacement round on the violence experienced prior to displacement and all 14 pre-displacement food access variables contained in the WFP survey from the most recent pre-displacement survey to which the household responded.<sup>19</sup> If better-off household were less likely to drop out of the survey and change the composition of the sample, we might expect better pre-displacement food access to be positively associated with the probability of responding to post-displacement rounds, especially for later rounds.

However, there is little correlation between pre-displacement food access indicators and the likelihood of responding to any single post-displacement round. For each of the thirteen rounds after displacement (month of displacement and 12 following months), the table reports the p-value of the hypothesis test of all pre-displacement characteristics jointly equaling zero. Only one of the 13 p-values is statistically significant at the 10 percent level, which is what would be expected if there were no relationship; and the p-values themselves vary between 0.065 and 0.915.

Third, the survey can only be representative of the mobile phone-using population. Although it is difficult to identify exactly how access to mobile phones has changed since the onset of the conflict, all evidence suggests that access has remained high. Approximately 85 percent of the population lived in a household that owned at least one mobile phone prior to the conflict, and this figure was high across the entire country and among vulnerable groups<sup>20</sup> ; there is anecdotal evidence that the share with access to mobile phones remained high following the start of the conflict (although some households re-

> 19Specifically, the independent variables for each regression are the number of times the household consumed staples, pulses, vegetables, fruits, proteins, dairy, sugars, and fats in the past week in the most recent pre-displacement survey answered (eight separate variables); the number of times in the past week the household relied on less expensive foods, borrowed to purchase food, reduced the number of meals consumed, limited portion sizes of meals, and restricted consumption in the most recent predisplacement survey answered (five separate variables); an indicator equaling one if the household received food assistance in the most recent pre-displacement survey; and the number of fatalities from violent incidents and the number of violent incidents in the month before displacement. The specifications do not include the FCS nor the rCSI because they are linear combinations of the above set of variables. The specifications also include month-year indicators and district fixed effects. Each specification includes the entire sample of households used in the baseline specification- 1,116. See Appendix 5 for the coefficient estimates from each of the specifications.

> 20Prior to the escalation of the conflict, the share of households owning at least one mobile phone remained high for the rural population (81 percent), the population living below the poverty line (77 percent), and the population of all governorates (over 60 percent for each). Authors’ calculations using the 2014 Household Budget Survey.

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