Comments on Jardina and Piston 2021 "The Effects of Dehumanizing Attitudes about Black People on Whites' Voting Decisions"

The British Journal of Political Science published Jardina and Piston 2021 "The Effects of Dehumanizing Attitudes about Black People on Whites' Voting Decisions".

---

1.

Jardina and Piston 2021 used the "Ascent of Man" measure of dehumanization, which I have discussed previously. Jardina and Piston 2021 subtracted participant responses to the 0-to-100 measure of perceptions of how evolved Blacks are from participant responses to the 0-to-100 measure of perceptions of how evolved Whites are, and placed this difference on a 0-to-1 scale.

Jardina and Piston 2021 placed this 0-to-1 measure of dehumanization into an OLS regression with controls, took the resulting coefficient, such as 0.60 in Table 1 (for which the p-value is less than p=0.001), and halved that coefficient, so that, for the 0.60 coefficient, moving from the neutral point on the dehumanization scale to the highest measured dehumanizing about Blacks relative to Whites accounted for 0.30 points on the outcome variable scale, which for this estimate was a 0-to-100 feeling thermometer rating about Donald Trump placed on a 0-to-1 scale.

However, this research design means that 0.30 points on a 0-to-1 scale is also the corresponding estimate of how much dehumanizing about Whites relative to Blacks affected feeling thermometer ratings about Donald Trump. Jardina and Piston 2021 thus did not permit the estimate of the marginal effect of dehumanizing Blacks to differ from the estimate of the marginal effect of dehumanizing Whites.

I discussed this before (1, 2), but it's often better to not assume a linear association for continuous predictors (citation to Hainmueller et al. 2019).

Figure 3 of Jardina and Piston 2021 censors the estimated effect of dehumanizing Whites, by plotting predicted probabilities of a Trump vote among Whites but restricting the range of dehumanization to run from neutral (0.5 on the dehumanization measure) to most dehumanization about Blacks (1.0 on the measure).

---

2.

Jardina and Piston 2021 claimed that "Finally, our findings serve as a warning about the nature of Whites' racial attitudes in the contemporary United States" (p. 20). But Jardina and Piston 2021 did not report any evidence that Whites' attitudes in this area differ from non-Whites' attitudes in this area. That seems like a relevant question for researchers interested in understanding racial attitudes.

If I'm reading page 9 correctly, Jardina and Piston 2021 reported on original survey data from a 2016 YouGov two-wave panel of 600 non-Hispanic Whites, a 2016 Qualtrics survey of 500 non-Hispanic Whites, a 2016 GfK survey of 2,000 non-Hispanic Whites, and another 2016 YouGov two-wave panel of 600 non-Hispanic Whites.

The funding statement in Jardina and Piston 2021 acknowledges only Duke University and Boston University. That's a lot of internal resources for surveys conducted in a single year, and I don't think that Jardina and Piston 2021 limiting the analysis to Whites can be reasonably attributed to a lack of resources.

The Qualtrics_BJPS.dta dataset at the Dataverse page for Jardina and Piston 2021 has cases for 1,125 Whites, 242 Blacks, 88 Asians, 45 Native Americans, and 173 coded Other, with respective non-Latino cases of 980, 213, 83, 31, and 38. The Dataverse page doesn't have a codebook for that dataset, and the relevant variable names in that dataset aren't clear to me, but I'll plan to post a follow-up here if I get sufficient information to analyze responses from non-White participants.

---

3.

Jardina and Piston 2021 suggested (p. 4) that:

We also suspect that recent trends in the social and natural sciences are legitimizing beliefs about biological differences between racial groups in ways that reinforce a propensity to dehumanize Black people.

This passage did not mention the Jardina and Piston 2015/6 TESS experiment in which participants were assigned to a control condition, or a condition with a reading entitled "Genes May Cause Racial Difference in Heart Disease", or a condition with a reading entitled "Social Conditions May Cause Racial Difference in Heart Disease".

My analysis of data for that experiment found a p<0.01 difference between treatment groups in mean responses to an item about whether there are biological differences between Blacks and Whites, which suggests that the treatment worked. But the treatment didn't produce a detectable effect on key outcomes, according to the description of results on the page for the Jardina and Piston 2015/6 TESS experiment, which indicates that "Experimental conditions are not statistically associated with the distribution of responses to the outcome variables". This null result seems to be relevant for the above quoted suspicion from Jardina and Piston 2021.

---

4.

Jardina and Piston 2021 indicated that "Dehumanization has serious consequences. It places the targets of these attitudes outside of moral consideration, ..." (p. 6). But the Jardina and Piston proposal for the 2015/6 TESS experiment had proposed that some participants be exposed to a treatment that Jardina and Piston hypothesized would increase participant "biological racism", to use a term from their proposal.

Selected passages from the proposal are below:

We hypothesize that the proportion of respondents rating whites as more evolved than blacks is highest in the Race as Genetics Condition, lower in the Control Condition, and lowest in the Race as Social Construction Condition.

...Our study will also inform scholarship on news media communication, demonstrating that ostensibly innocuous messages about race, health, and genetics can have pernicious consequences.

Exposing some participants to a treatment that the researchers hypothesized as having "pernicious consequences" seems like an interesting ethical issue that the proposal didn't discuss.

Moreover, like some other research that uses the Ascent of Man measure of dehumanization, the Jardina and Piston 2015/6 TESS experiment included the statement that "People can vary in how human-like they seem". I wonder which people this statement is meant to refer to. Nothing in the debriefing indicated that this statement was deception.

---

5.

The dataset for the Jardina and Piston 2015/6 TESS experiment includes comments from participants. I thought that comments from participants with IDs 499 and 769 were worth highlighting (the statements were cut off in the dataset):

I disliked this survey as you should ask the same questions about whites. I was not willing to say blacks were not rational but whites are not rational either. But to avoid thinking I was prejudice I had to give a higher rating. All humans a

Black people are not less evolved, 'less evolved' is a meaningless term as evolution is a constant process and the only difference is what particular adaptations a group has. I don't like to claim certainty about things of which I am unsure, a

---

NOTES

1. The Table 3 header for Jardina and Piston 2021 indicates that vote choice is the outcome for that table, but the corresponding note indicates that "Higher values of the dependent variable indicate greater warmth toward Trump on the 101-point feeling thermometer". Moreover, Figure 3 of Jardina and Piston 2021 plots predicted probabilities of a vote for Trump, but the figure note indicates that the figure was "based on Table 4, Model 4", which is instead about warmth toward Obama.

2. Jardina and Piston 2021 reported results for participant responses about the "dehumanizing characteristics" of "savage", "barbaric", and "lacking self-restraint, like animals", so I checked how responses to the "violent" stereotype item associated with two-party presidential vote choice in data from the ANES 2020 Time Series Study.

Results indicated that, compared to White participants who rated Whites as being as violent on average as Blacks, White participants who rated Blacks as being more violent on average than Whites were more likely to vote for Donald Trump net of controls (p<0.05). But result also indicated that, compared to White participants who rated Whites as being as violent on average as Blacks, White participants who rated Whites as being more violent on average than Blacks were less likely to vote for Donald Trump net of controls (p<0.05). See lines 105 through 107 in the output.

3. Jardina and Piston 2021 reported that, in their 2016b YouGov survey, 42% of Whites rated Whites as more evolved than Blacks (pp. 9-10). For a comparison, the Martherus et al. 2019 study about Democrat and Republican dehumanization of outparty members reported dehumanization percentages of "nearly 77%" (2018 SSI study) and "just over 80%" (2018 CCES study).

4. Data sources:

American National Election Studies. 2021. ANES 2020 Time Series Study Preliminary Release: Combined Pre-Election and Post-Election Data [dataset and documentation]. March 24, 2021 version. www.electionstudies.org.

Ashley Jardina and Spencer Piston. 2015/6. Data for: "Explaining the Prevalence of White Biological Racism against Blacks". Time-sharing Experiments for the Social Sciences. https://www.tessexperiments.org/study/pistonBR61

Ashley Jardina and Spencer Piston. 2021. Replication Data for: The Effects of Dehumanizing Attitudes about Black People on Whites' Voting Decisions, https://doi.org/10.7910/DVN/A3XIFC, Harvard Dataverse, V1, UNF:6:nNg371BCnGaWtRyNdu0Lvg== [fileUNF]