Fifth, table 2 demonstrates that there appears to be little relationship between violence and food access in both regions controlled by the internationally‐recognized government and the rest of the country. Specifically, column (6) re‐estimates the baseline specification but interacts the violence measure with an indicator equaling one if the respondent resided in regions not controlled by the internationally‐ recognized government. Only one of the coefficients is marginally significant (relationship in regions not controlled by the internationally‐recognized government), and the upper bound of the confidence interval for both estimates corresponds to a very small decrease in access to food in response to a doubling of fatalities in a month.

Sixth, it is possible that violence is causing a much larger decline in access to food, but food assistance targeted to violence‐prone regions is mitigating its effects. However, table 2 demonstrates that this explanation is not likely. The WFP survey began inquiring about whether the household is receiving food assistance beginning in 2017, and column (7) includes this in the baseline specification. The estimate is qualitatively identical with the addition of food assistance to the specification.

And lastly, it is not likely that the lack of a correlation between violence and food coping strategies is being completely driven by internal displacement. The primary concern is that those who were worst affected by the conflict simply left the governorate before the next month’s survey to re‐locate where it was safer, and this could obscure the identification of the correlation. However, the WFP data collect information on the displacement status of households, and the date of displacement and the governorate from where the household moved. In the WFP survey to which we have access to the unit‐level data (November 2017), only 8 households (of more than 2,422) reported to have been displaced from their original governorate the month before. And this is despite the fact that there was significant violence in October 2017, including 6 governorates that had more than 100 fatalities each.

# **Impact of Port Blockages and the Tightening of the Ports**

Although we find little correlation between the local effects of violence and food access, we find further evidence of the supply chain blockages having an immediate and significant effect. The monthly mobile phone surveys began after imports through the ports supplying the north of the country significantly dropped (e.g., WFP 2017), and it is difficult to estimate how food access changed in response. However, we analyze the effects on food access of a sharp event that caused this port blockage to get significantly worse.

Specifically, we use the complete sea and air blockade of _all_ of Yemen’s ports (not just the ports that supply the north),<sup>20</sup> and compare food access of those surveyed immediately before to those surveyed immediately after the event. Importantly, there was an ongoing mobile phone survey conducted by the World Food Programme (WFP) that interviewed 2,424 respondents. Of these interviews, approximately 900 occurred in the five days before the blockade was implemented; approximately 900 occurred during the full blockade on the entire country (November 6‐13); and approximately 600 occurred during the time period during which only northern ports were blockaded (November 13‐November 18). The ongoing survey and the distribution of responses over time allows one to gauge how households adapted to the economic difficulties, and whether this affected their access to food.

> 20 For example, see (accessed April 2017) <u>https://reliefweb.int/report/yemen/escalating‐humanitarian‐crisis.</u>

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