Alternatively, the empirical specifications demonstrate that food access was significantly worse in the northern parts of the country that are largely controlled by Houthi forces. The fact that food access tended to be worse in the north could be indicative of both the tightening of the ports and the lack of government salaries adversely affecting food security. The ports that supply the north have been subjected to more pressure than ports in regions controlled by the internationally‐recognized government, and reports suggest that government salaries have been paid less often in those same regions (e.g., WFP 2017). However, the worse food security outcomes could also be due to other conflict‐ related factors, such as poor governance and oversight given the lack of control by the internationally‐ recognized government.<sup>8</sup> However, there is further evidence that the tightening of the ports in particular had a large and immediate impact on the population. During November 2017, there was an unexpected air and sea blockade of the entire country, which dramatically worsened the disruption to the supply chains. One of the monthly WFP mobile phone surveys was being fielded as this blockade was implemented, and one can observe an immediate and significant decline in food access overnight. Given the speed with which households were affected, these results suggest that food supplies in the country are very tight and have been substantially stressed by the difficulty in importing goods over the course of the conflict.

There are two primary contributions of these results. First, the finding that violence is less correlated with levels of welfare than other conflict‐related shocks contrasts with findings in other settings where aggregate economic outcomes, firm outcomes, and individual employment outcomes are adversely affected by violence (e.g., Abadie and Gardeazaba 2003; Singh and Pedersen 2003; Guidolin and La Ferrara 2007; Collier and Duponchel 2013; Klapper et al. 2013; Ksoll et al. 2015; Amodio and Di Maio 2018; Tandon forthcoming; etc.).<sup>9</sup> Thus, these previous results might not generalize to this unique setting among the mobile phone‐using population.

Second, these results have important implications for the targeting of food assistance across Yemen. The most recent official IPC classification of food emergencies in Yemen, which is the basis for much of the food aid distributed in the country, has identified more violent regions as being closer to famine. The announcement explained the classification stating that “armed conflict remains the main driver of food security (IPC 2018).” The previous official IPC classification in 2017 also explicitly included indicators that correlated with violence, which resulted in governorates being more affected by violence receiving much more food assistance than the rest of the country (e.g., Tandon and Vishwanath 2019). However, the results here contrast with this narrative, and suggest that reducing the emphasis on violence in the identification of regions with poor food security could lead to better targeting of assistance.

# **Background: The Current Conflict in Yemen and Available Data**

The conflict in Yemen has been ongoing since the mid‐2000s. The Houthis' movement began as a theological movement that protested the national government. However, following this protest, the government used the military to try to arrest their leader, which led to a number of wars during which the group made few gains, and was repeatedly beaten back by the military.<sup>10</sup>

> 8 This pattern was not present just prior to the conflict in the 2014 Household Budget Survey (World Bank 2017).

> 9 See also Blattman and Miguel (2010) for a thorough review of the literature.

> 10 See (accessed July 2017): <u>http://www.aljazeera.com/news/middleeast/2014/08/yemen‐houthis‐hadi‐protests‐ 201482132719818986.html.</u>

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