The explanations above assume that people intend to report accurately but are prevented from doing so due to aspects of the situation. In some contexts, individuals may misreport due to expectations about the implications of the results of the study. For example, individuals may misreport to increase earnings in a study context (Mazar, Amir, and Ariely 2008) or to shape the results of the study if they believe that it will inform policy. In situations where individuals wish to influence a particular research outcome, a guise of anonymity will not shift their behavior. It is important to note that our concern is not with the ethics of individual misreporting – this is a reasonable response to contexts of extreme vulnerability – but rather to ensure that policymakers have access to data that enables them to adequately serve the vulnerable population as a whole.

Behavioral science is increasingly being used as a policy tool to help policymakers create better policy and solve collective action problems more effectively (World Bank 2015). This is based on research illustrating that people make decisions on the basis of both external and internal reward mechanisms (Mazar and Ariely 2006). Even in cases where people have an extrinsic incentive to misreport, this may be overridden by a preference for remaining consistent with their values. One example of this is when individuals’ beliefs regarding the consequences of misreporting affects their behavior. In an two‐person experiment where one participant can increase her payoff by misreporting but at the expense to her counterpart, Gneezy (2005) finds that individuals’ propensity to misreporting is sensitive to the costs it imposes on the other person. Contextual cues affect the salience of internal incentives (or intrinsic motivations) and thus the accuracy of responses. This psychological mechanism has been put to practical use in policy. In multiple contexts, normative messaging has been used to increase tax payments (Hallsworth et al. 2017; Hernandez et al. 2017) or reduce littering and environment theft (Cialdini 2003).

In this paper, we apply the tools of behavioral science to investigate the veracity of consumption reports by internally displaced persons (IDPs). In numerous rounds of data collection in Somalia and South Sudan, IDPs report significantly lower levels of consumption than non‐IDP households. In previous survey rounds 45 percent of Somali IDP households report food consumption below subsistence levels and approximately 80 percent below recommended levels (refer Figure 5). While the data may be accurate, there are two reasons to suspect that it is not. First, such high levels of non consumption would be associated with high rates of mortality due to starvation. Although being high, the mortality rates among IDPs suggest that this is not happening systematically across the country at such a scale (FEWS NET, 2018).<sup>3</sup> Second, non‐IDP households that are statistically similar on observable characteristics report higher levels of consumption than IDP households. While IDPs and non‐IDPs may

> 3 Although data from the USAID led Famine Early Warning Systems Network (FEWS NET) suggest high level of malnutrition, evidence on mortality across the counties is mixed (FEWS NET, 2018).

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