Research

In the wake of the January 2025 Los Angeles Fires, a dramatic shift in perception related to water systems and their ability to fight wildfires may have occurred. This study is the first to empirically examine the extent of regional public opinion regarding the role of water management in the LA fires, leveraging a unique, representative survey of 1,360 Los Angeles County households conducted in February and March 2025. This data source allows us to analyze the degree to which residents in the region who were affected by the fires to different degrees attribute blame for the wildfires to poor water management. It also enables us to study which specific household-level factors─including direct or indirect experience of the fires; political sentiment from partisan cues; and longer-standing socioeconomic, demographic, and behavioral elements─influence this attribution. We find descriptively that water management was the fifth most common factor perceived to be responsible for the fires’ impact. While several household-level characteristics correspond with this blame attribution, when we further examine potential explanations using multivariate regression techniques, we find that political sentiment from partisan cues was by far the most powerful explanatory factor.

Importance: Wildfires are projected to increase in frequency and severity, yet their mental health consequences, particularly the social factors associated with vulnerability, are not well understood. Objectives: To estimate the association between wildfire exposure and psychological distress and to assess the social factors that modify this association. Design, Setting, and Participants: In this longitudinal survey study, a probability-based internet panel of Los Angeles County residents in California was surveyed monthly, before and after the January 2025 wildfires, generating prefire measures of social vulnerability, postfire measures of wildfire impact, and prefire and postfire mental health assessments. Exposure: Residence in an evacuation warning or order zone during the January 2025 wildfires, based on respondents' residential census tracts. Main Outcomes and Measures: Psychological distress was measured monthly using the validated 4-item Patient Health Questionnaire (PHQ-4; range, 0-12, with higher scores indicating greater distress); subscales assessed anxiety and depression. Two-way fixed-effects (TWFE) models with respondent and month-year fixed effects were used to estimate wildfire-associated mental health changes. Results: The analytic sample included 1510 adults (mean [SD] age, 47.2 [15.5] years; 924 [61.2%] female) and 31 632 respondent-month observations spanning October 1, 2023, through December 31, 2025; at wildfire onset, 143 (9.5%) were residing in an evacuation order or warning zone. TWFE models interacting wildfire onset with evacuation zone residence indicated that evacuation zone residents experienced a 0.28-point greater increase in PHQ-4 score (β [SE] = 0.28 [0.09]; P = .002) after wildfire onset. This association showed no significant attenuation over the 11-month follow-up and was concentrated among individuals with household incomes below $100 000, extreme housing cost burden, prefire psychological distress, or limited instrumental social support. Subscale analyses suggest that the increase in PHQ-4 scores was associated primarily with increases in anxiety; after wildfire onset, evacuation zone residents exhibited greater increases in both anxiety (β [SE] = 0.17 [0.05]; P = .002) and depression (β [SE] = 0.12 [0.05]; P = .02), but only anxiety increased significantly from its prefire baseline. Conclusions and Relevance: In this longitudinal survey study of Los Angeles County residents, residential exposure to the January 2025 wildfires was associated with increased psychological distress, but only among individuals with preexisting psychosocial or economic vulnerabilities. Policies that strengthen housing security and instrumental support networks may reduce wildfire-related mental health burdens.

Objectives: To examine associations between partisan political identification and self-reported acetaminophen (paracetamol) use after revised federal guidance on acetaminophen issued by the current administration in September 2025. Study design: Repeated cross-sectional analysis of longitudinal monthly panel survey data collected from October 2025 to December 2025. Methods: Regression analysis of longitudinal survey data from the Understanding America Study (UAS), a nationally representative internet panel of over 14,000 US adults, spanning from October 2025 to December 2025. Using data on self-reported acetaminophen use and political identification over time, probability of acetaminophen use, Tylenol® use, and non-Tylenol® acetaminophen use are estimated by partisan identity (Democrat, Republican, and independent). Results: 43.6% of respondents reported past-month acetaminophen use. Compared to Democrats, Republicans (OR = 0.908, 95% CI 0.833–0.988) and Independents (OR = 0.821, 95% CI 0.744–0.905) had significantly lower odds of any acetaminophen use. This effect was driven primarily by Tylenol® use (Republican OR = 0.843, 95% CI 0.771–0.922; Independent OR = 0.814, 95% CI 734–.901). Republicans had significantly higher odds of using non-Tylenol® acetaminophen compared to Democrats (OR = 1.134, 95% CI 1.018–1.262). Conclusions: Partisan political identity is associated with differential patterns of acetaminophen use following revised federal guidance. Republicans reported lower Tylenol® use but higher use of other acetaminophencontaining medications, suggesting that partisan cues may shape brand-specific drug behaviour.

Research examining the individual impacts of wildfires has found that wildfires are associated with worse mental health, more physical illness, and increased financial strain. However, these results often rely on local surveys fielded after a wildfire occurs and there is little to no understanding of how post-wildfire differential non-response may bias these estimates of impact. If those individuals most impacted by the wildfire are unwilling or unable to respond to post-wildfire surveys, this would lead to underestimating wildfire impacts. If individuals who are less impacted are less willing to respond, wildfire impacts will be overestimated. We use monthly panel data from the Understanding America Study and its LABarometer subpanel to study differences in response rates among Los Angeles County residents before and after the January 2025 Palisades and Eaton wildfires. By matching survey respondents with geocoded data on wildfire exposure, we find some evidence that response rates declined in post-wildfire months among respondents residing in census tracts in closer proximity to the burn zone, under evacuation orders, or under evacuation warnings. However, these effects are of short and inconsistent duration.

U.S. public opinion has traditionally supported Israel in the context of the Israeli–Palestinian conflict. However, in recent years, support for Israel has declined, especially among younger left-leaning Americans. At the same time, Israel has received unprecedented criticism from international human rights organizations and left-wing Jewish-American organizations for its treatment of Palestinians in the occupied territories, particularly with respect to its military campaigns in Gaza. Has critical information from these sources helped shape U.S. public opinion of the conflict? We conduct a survey experiment analyzing the extent to which information from Human Rights Watch and Jewish Voice for Peace impacts views of who is to blame for the 2021 Israel-Gaza conflict. We find individuals who are treated with criticism of Israel from Jewish Voice for Peace or are informed of the death toll of the 2021 Israel-Gaza conflict (which killed far more Palestinians than Israelis) to be more likely to blame Israel for the violence and to support U.S. foreign policy taking a more pro-Palestinian stance. The effects of the treatment are stronger amongst Democrats and independents than Republicans. These results demonstrate that critical cues from Jewish-American organizations and death-toll information negatively impact U.S. public opinion toward Israel.

Recruitment into longitudinal survey panels has declined in recent years. In response, researchers have experimented with various strategies to improve the effectiveness of recruitment materials. However, rarely, if ever, are recruitment materials subjected to qualitative testing prior to their deployment. We adopted a mixed-methods approach to improve and experimentally evaluate recruitment materials for the Understanding America Study (UAS), a probability-based online panel of U.S. adults. Qualitative analysis identified several issues with existing recruitment materials, including a lack of clarity about the opportunity to participate in future paid surveys after joining the panel, confusion about data privacy and use, the need for easier online access to the initial survey, and concerns about the length and complexity of the invitation letter. After revising the recruitment materials based on the qualitative results, we conducted an experiment to evaluate the effect of a new invitation letter, with Frequently Asked Questions (FAQs) printed on its reverse side, on panel recruitment. We find that the new recruitment letter increased both the proportion of respondents who agreed to join the panel and, among those completing the initial survey, the share who ultimately became panel members. Mediation analysis reveals that this effect operates primarily through increased online completion of the initial survey, likely facilitated by the addition of a QR code in the revised letter that provides direct online access to the survey. This result corroborates a key aspect of the qualitative results.

This study examines how major life events influence subjective well-being, focusing on differences between life satisfaction and momentary affect. Using Ecological Momentary Assessment (EMA) data from a nationally representative panel of adults aged 50 and older, we analyze responses to significant life events, including health issues, financial shocks, and bereavements. Participants reported their wellbeing during baseline “random bursts” and subsequent “triggered bursts” following life events. Results reveal that while life satisfaction exhibits significant changes in response to these events, momentary affect remains largely unaffected, with smaller or statistically insignificant effects. Notably, the impacts of participant age and the day of the week on momentary affect exceeded those of life events. These findings support the “focusing hypothesis,” suggesting that while life satisfaction may adapt to significant circumstances, day-to-day emotional experiences are more resilient.

Climate change and its effects will impact populations differently depending on a number of geographic and individual vulnerabilities, yet studies are conflicting as to whether those more vulnerable to climate change express greater levels of concern. These conflicting reports may be due to the fact that interpretations of climate vulnerability are intensely specific to individuals and because these vulnerabilities are moderated through the lens of partisanship. This paper examines the lack of residential air conditioning as a marker of climate vulnerability and how the effect of air conditioning on climate change views differs by partisan leaning. Using data from the Understanding America Study’s Los Angeles Barometer survey, this analysis shows that Republicans in Los Angeles County who lack central air conditioning, and are thus more vulnerable to hot temperatures, are more likely to consider climate change a human-caused threat and more likely to support individual and government action to address climate change than Republicans with central air conditioning. In contrast, lack of air conditioning only somewhat or insignificantly affects climate change views among Democrats. The results suggest not only that the climate change views of Republicans are amenable to personal vulnerability but also that adaptation measures may lead to reduced concern about climate change.

BACKGROUND: Democrats are more likely to be vaccinated for COVID-19 than Republicans. It is unknown if political polarization surrounding the COVID-19 vaccine has affected flu vaccine uptake. The purpose of this study is to examine the partisan differences in annual flu vaccine uptake before and after the COVID-19 pandemic. METHODS: This study uses longitudinal panel survey data from the Understanding America Study (UAS), spanning from 2015 to 2024. Using self-reported flu vaccination and partisanship over time, I estimate the odds ratios of flu vaccination for partisan groups before the COVID-19 pandemic, during the pre-vaccination phase of the COVID-19 pandemic, and after the rollout of the COVID-19 vaccine. RESULTS: In pre-COVID years, the predicted probability of flu vaccination was 0.54 ([0.52,0.56], P < .000) among Republicans and 0.63 ([0.61,0.64], P < .00) among Democrats. After the roll-out of the COVID-19 vaccine, the average flu vaccination probability was 0.44 ([0.43,0.46], P < .00) among Republicans and 0.61 ([0.59,0.62], P < .00) among Democrats. CONCLUSIONS: The COVID-19 pandemic increased the partisan gap in annual flu vaccination. Researchers should continue to investigate if the partisan gap in other types of vaccinations has grown post-COVID. Practitioners may need to tailor their flu vaccine messaging to vaccine-hesitant political demographics.

Recent surveys have shown that significant numbers of partisans in the United States harbor violent attitudes towards out-party politicians and out-party members. This finding has corresponded with the increased visibility of political fringe groups, such as Antifa on the political left and QAnon on the political right. Fringe groups such as these take ideologically extreme political positions and defy political norms, including prohibitions on political violence. Are partisan supporters of these fringe groups more likely to hold violent political attitudes? Using survey data from the Understanding America Study (UAS), we test whether Antifa supporters and QAnon supporters are more likely to report violent attitudes compared to non-fringe group supporters. We find supporters of both groups are more likely to wish harm towards out-party members, support violent protest, and support various forms of interpersonal violence towards out-party members. The results hold even when controlling for ideological extremity, personality, and affective partisanship.

Recent polling shows significant levels of radical partisanship among the US public in the form of violent partisan schadenfreude and violent partisan attitudes. Previous research shows that the partisan intensity underlying these sentiments increases around presidential elections and when political actors use violent rhetoric. Has lethal mass partisanship declined in the years after the 2020 election, especially now that one of the main purveyors of violent rhetoric has left office? This paper uses panel data from the Understanding America Study (UAS) to show how levels of radical partisanship have changed from the post-election period of 2020 to the same time period in 2021 and 2022. The results demonstrate that rates of violent partisan attitudes have declined in 2021 and 2022 compared to 2020, especially amongst those who were most supportive of former President Donald Trump. However, changes in partisan schadenfreude have no discernable pattern. The results demonstrate both that radical partisanship is not on a uniformly upward trajectory but likely decreases and increases with changes in political context, and that elements of radical partisanship do not vary in parallel.

Previous studies show Republicans have lower risk perceptions of COVID-19 than Democrats. Has this gap in risk perception been consistent throughout the course of the pandemic? Using longitudinal data from the Understanding America Study’s Understanding Coronavirus in America longitudinal panel survey, we examine how time and vaccination status have changed Republican and Democratic risk perceptions of engaging in various activities (such as grocery shopping, visiting friends and family etc.) as well as risk perceptions of infection, hospitalization, and death due to COVID-19. We find that while Republicans have lowered their perceived risk of activity more than Democrats over time, vaccinated Democrats have lowered their perceived risk of infection, hospitalization, and death more than vaccinated Republicans. These results are robust to inclusion of media consumption and social media use. This divergence on the two measures of risk from COVID-19 may complicate leaders’ efforts to move on from the politics of the pandemic toward a return to “normal.”

According to policymakers, US national values shape US foreign aid policy. However, these national values clash with material interests when policymakers are faced with the decision of whether or not to grant US military aid to countries that do not adhere to US national values but do serve US security and economic interests. To what extent are US national values resilient to clashes with these material interests? This paper hypothesizes that national values are resilient to clashes with interests to the extent to which these values are a salient feature of US national identity. The findings indicate that more prominent values (democracy) are almost impervious to countervailing interests while more tangential values (enterprise and human rights) exhibit different effects on US military aid allocation depending on the security and economic importance of the recipient state.

Objective We examine the role of how a hostile discourse toward Islam influences American public opinion regarding U.S. foreign policy actions toward Muslim populations and Muslim‐majority nations. Methods Using a survey experiment with two vignettes, we test how Americans’ foreign policy preferences are affected by Islamic identity. In the first vignette, a minority group is facing ethnic cleansing. Second, a country is developing chemical weapons. Results We find that Americans are less likely to see Muslim minorities abroad as under threat or to support costly foreign policy actions to assist them. We also find that Americans are more likely to see Muslim countries as threatening and to support the use of military force against Muslim states. Conclusion Our evidence suggests that the political effects of Islamophobia are not restricted to domestic policy but include foreign policy preferences too.

President Trump verbally attacked human rights in his campaign rhetoric in 2016, leading many to believe that he would undermine the role of human rights in US foreign policy as President. I examine whether or not President Trump’s anti-human rights rhetoric manifested in US foreign policy by analyzing potential changes in how human rights were considered in foreign aid allocations under the Trump Administration. While President Trump had a number of executive tools at his disposal to exert control over foreign aid allocation, he would still have had to overcome considerable bureaucratic and legislative inertia in order to implement his anti-human rights agenda in US foreign aid. I demonstrate that he was unsuccessful in overcoming this inertia, at least in the first two years of his Administration (the years for which data is currently available). If anything, human rights received more consideration under President Trump than under President Obama.

This paper theorizes that the effect of human rights violations on US economic aid is conditioned by the salience of US national security concerns. National security concerns will be more salient in situations where recipients contribute to maintaining US security and in temporal eras when the USA is perceived as being under increased external threat. As the relational and temporal salience of national security increases, any negative effect of human rights violations on US economic aid should decrease. I test this hypothesis by examining US economic aid allocations to states from 1977 to 2005. The results show that the salience of national security concerns present in the US-recipient relationship does condition the relationship between human rights violations and US economic aid. There are also significant differences between different temporal eras of US foreign aid allocation. Future work should address how conflicts between interests and values in US foreign policy are negotiated.