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Published in final edited form as: Hum Nat. 2023 Dec 20;34(4):605–620. doi: 10.1007/s12110-023-09466-y

Perceptions of Income Inequality and Women’s Intrasexual Competition

Abby M Ruder 1, Gary L Brase 1, Nora J Balboa 1, Jordann L Brandner 2, Sydni A J Basha 3
PMCID: PMC10947790  NIHMSID: NIHMS1970155  PMID: 38114790

Abstract

Income inequality has been empirically linked to interpersonal competition and risk-taking behaviors, but a separate line of findings consistently shows that individuals have inaccurate perceptions of the actual levels of income inequality in society. How can inequality be both consistently misperceived and yet a reliable predictor of behavior? The present study extends both these lines of research by evaluating if the scope of input used to assess income inequality (i.e., at the national, state, county, or postal code level) can account for perception discrepancies and if actual/perceived inequality is associated with female intrasexual competition. Female participants recruited online from the general US population (n = 691) provided demographic information, measures of perceived income inequality, and measures of intrasexual competition attitudes and behavior. Actual and perceived income inequality (at any level) did not predict negative attitudes toward other women or female weighting of physical appearance as a desirable trait. Perceived income inequality and actual county-level inequality was, however, predictive of female competition in the form of self-sexualization clothing choice. Further analyses found that age and importance placed on physical attractiveness also predicted women’s clothing choices. Perceptions of income inequality were predicted not by actual Gini indices, but by beliefs about the levels of poverty and income gaps. These results highlight the importance of better understanding the proximate cues by which people perceive environmental features such as inequality, and how those cues are used to adjust interpersonal behaviors.

Keywords: Income inequality, Intrasexual competition, Perceived inequality, Self-sexualization

Power can be a great aphrodisiac (per Henry Kissinger, primarily referencing women), but it also is a zero-sum resource; if I have power over you, your own power is reciprocally diminished. To the extent that women place differential weight on power as a desirable trait, it will tend to create differences in the desirability of potential partners. Men will compete with other men for power; women will compete with other women for powerful men. Though simplistic, this is generally true (e.g., Hopcroft, 2006, 2021; Nettle & Pollet, 2008; Voland, 1990; Weeden et al., 2006). Further, to the extent that more money translates to greater power in modern societies, this pattern also should be exacerbated by higher levels of income inequality. It has, in fact, been found that income inequality exacerbates intrasexual competition (see below). This creates an apparent paradox, though, because a separate research literature has documented that people pervasively misperceive the degree of income inequality in their environment. How, then, do people accurately calibrate their competition based on a variable which they do not accurately perceive?

Income Inequality

Income inequality refers to the distribution of how much people earn within a given period relative to other earners, with one of the most common measures of inequality being the Gini index; a measurement of the difference between a completely equal distribution of income within a population and the actual cumulative proportion of people at different income levels (Furman et al., 2019). Thus, a Gini index varies from 0 to 1, with 0 being perfectly equal and 1 being perfectly inequal populations.

For practical purposes, actual Gini index numbers tend to be on the low end of the theoretical range and small differences are of substantial practical importance. Thus, the United States has a relatively high a Gini index of 0.415 for a developed nation (versus, for comparison, 0.292 [Netherlands], 0.293 [Sweden] and 0.256 [Ukraine]; World Bank, 2022). Less-developed and lower-income nations often have comparable or higher Gini indices (e.g., 0.489 for Brazil, 0.542 for Colombia, and 0.454 for Mexico; World Bank, 2022). Because the United States is geographically large and diverse, there are also state-level Gini indexes (World Population Review, 2022) which range from 0.417 (Alaska) to 0.510 (New York).

A growing research literature indicates that most people, however, are either unaware of or systemically mistaken about the degree of income inequality in their societies (Norton & Ariely, 2011). For example, the International Social Survey Project (ISSP Research Group, 2017) found that participants worldwide were able to correctly identify the income distribution for their country of residence about 29% of the time from a set of five options (Fig. 1). This represents only slightly better than chance accuracy. For reference, the estimated Gini indices corresponding to the distributions in Fig. 1 (Gimpelson & Treisman, 2017) are Type A (0.42), Type B (0.35), Type C (0.30), Type D (0.20), and Type E (0.21).

Fig. 1.

Fig. 1

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Five diagrams of possible inequality distributions of societies, used in the International Social Survey Project survey (ISSP Research Group, 2017)

Multiple international economic surveys have also shown large inaccuracies in estimated average salaries of different occupations, the percentage owned by the wealthiest 1%, poverty rates, representation in income deciles, and overall levels of changing inequality (Gimpelson & Treisman, 2017). There seems to be a general inability of participants to accurately gauge the economic state of their county and how it impacts them (Hauser & Norton, 2017).

Misperceptions of actual income inequality is concerning because it has pervasive negative effects on economic growth, skill development and social mobility, constructive public policy, and political stability (e.g., Cingano, 2014; Krupp & Cook, 2018; Luberti et al., 2020; Schmalor & Heine, 2022; Willis et al., 2022). For example, it is generally thought that, holding all else equal, greater national inequality fosters greater demands for redistribution which fuels reactionary revolutions and less democratization (Gimpelson & Treisman, 2017). Inequality can generally lead people to seek out more high-risk, high-reward situations and—of particular interest here—engage in more intense intrasexual competition. Yet these general socio-economic phenomena seem to imply good sensitivity to actual levels of income inequality, even as other research results indicate people consistently misperceive those levels.

Intrasexual Competition

Intrasexual competition in nonhuman animals tends to be fairly direct conflict between members of the same sex to improve access to potential mates or to resources (e.g., territory) needed for that access. Research on human intrasexual competition has found similar, albeit often less direct, competitive behaviors among men and women. For both, the goals are often to strategically derogate potential rivals and engage in self-promotion tactics in order to successfully compete for potential mates (Buss & Dedden, 1990; Campbell, 1999; Karimi-Malekabadi et al., 2019). These derogation and self-promotion tactics center around traits that are valued for their reproductive potential and investment by the opposite sex. For example, men often self-promote in terms of resource acquisition and derogate rivals in displays of aggression (e.g., Griskevicius et al., 2009) as women tend to prefer status- and resource-associated traits (Buss, 1988). For women, intrasexual self-promotion often tends to involve domains of physical attractiveness (Davis & Arnocky, 2022; Wang et al., 2021) and rival derogation includes tactics such as indirect and verbal aggressiveness (Buunk & Fisher, 2009; Fisher & Cox, 2009; Fisher & Krems, 2023; Krems et al., 2022; Reynolds, 2022; Vaillancourt & Sharma, 2011; Vaillancourt, 2013).

Competitive behavior among women regarding physical attractiveness can lead to self-sexualizing: emphasizing one’s sexual appeal and physical traits by wearing more revealing clothing or acting more provocatively (Blake et al., 2018). For example, previous research has found that women who were expecting their “crush” at a hypothetical party they were attending with an attractive friend chose significantly more attractive and revealing clothes than women who were attending with a less attractive friend (Olson et al., 2020). This research suggests that women may increase their intrasexual competitiveness by self-sexualizing when they perceive a bigger “threat” compared to other conditions. Keys and Bhogal (2016) found that, when around a suggestively and provocatively dressed woman, female participants tended to use more negative and derogatory words to describe that woman than when she was more conservatively and modestly dressed.

Blake and colleagues (2018) found a positive relationship between female self-sexualization in social media posts and income inequality within specific regions, particularly in developed nations such as the United States. In contrast to earlier thoughts that sexualization of women was largely based on gender oppression, objectification, and gender inequality, Blake et al. argued based on this social media evidence that women sexualize themselves even in nations that are not gender oppressive and do this more so in areas of relatively high income inequality. Importantly, this evidence implies that women who sexualize themselves may be mentally tracking the levels of income inequality and of competition in their environments. Furthermore, Blake and Brooks (2019b) suggest that aggregate sales of goods and services related to enhancing women’s appearances will increase in areas of high-income inequality because women could perceive those products as enhancing their desirability and signaling high-status.

Research Questions and Hypotheses

This recent evidence suggesting links between income inequality and female self-sexualization raise several questions. As reviewed above, people are poor estimators of income inequality, yet at the same time it appears that even relatively slight income inequality differences influence social behaviors such as intrasexual competition. How are these things both correct?

The present research focuses on two issues that fall out of this apparent contradiction. First, are perceptions of income inequality seemingly inaccurate because people experience income distributions only within a small segment of the population? For example, rather than country-level inequality, perhaps people are only able to evaluate state, county, or even local region inequalities; variations in income that they have actually experienced. Objective data on income inequality is often considered at the national, or occasionally the state, level. To the extent that people are estimating inequality based on their own lived experience, though, their data may be quite different. It may be more accurate to look at scales such as the county or postal code in which someone lives for their subjective income inequality.

Second, does income inequality influence social judgments and behaviors directly, while perhaps largely bypassing conscious perceptions and judgments (hence resolving the apparent contradiction)? Conscious awareness is not a necessary part of behavior changes in response to the environment (Hollands et al., 2016). For instance, learning by classical and operant conditioning can occur without conscious awareness. It is possible that cues of income inequality are exerting their influence on behavior, including female intrasexual competition, without conscious awareness of that influence’s origins. Indeed, these questions connect with a critical commentary about the ability to infer key proposed relationships in the Blake et al. (2018) results (Borgerhoff Mulder, 2018).

In a sense, only once we have a better idea of the reference class with which people are judging income inequality can we then evaluate how well or poorly they are judging it. Subsequently, the relationship can be assessed between these judgments of income inequality (or actual inequality) and women’s self-sexualization as an aspect of intrasexual competition.

Therefore, a first set of analyses were based on hypotheses replicating and extending prior findings. We expected that greater perceived levels of income inequality will be associated with women:

  1. having more negative attitudes toward same-sex others (the female intrasexual attitudes hypothesis).

  2. being more likely to endorse themselves dressing suggestively (the suggestive dressing hypothesis).

  3. rating physical appearance traits significantly higher in importance (the desirable traits hypothesis).

A second set of planned exploratory analyses were based on the hypothesis that the scope of input used to perceive income inequality (i.e., at the national, state, county, postal code, or societal grouping levels) could be clarified by looking at possible differential relationships between these alternative types of income inequality measures and the above measures of attitudes toward same-sex others, self-sexualization, and emphasis on physical appearance.

Methods

Participants

Participants were recruited from Amazon’s Mechanical Turk using Cloud Research, an online research and participant recruitment tool (Litman et al., 2017), and were compensated with $0.25 for successful completion of the study. Participation was restricted to women who were current residents of the United States (for purposes of using relevant Gini index data). Of the 979 total responses, 187 participants were removed for failing an English literacy question and 90 participants were removed for failing either of two attention check questions. Additionally, four participants were removed for self-identifying as a man, and seven participants were removed for not disclosing their sex or gender or self-identifying as non-binary. This left a final total of 691 responses. The majority of these participants were White or Caucasian (68.6%), heterosexual (80.6%), and cisgender (99.4%). Participant ages ranged from 18 to 78 years old, with the average being 42 years old. Additionally, 64.7% of participants were married or in a relationship and 89.8% had a reported a gross household income below $100,000 per year.

Materials and Procedure

Participants responded to a variety of measures and self-report scales via an online survey platform (Qualtrics). After giving their informed consent, filling out both a Captcha and English competency question to determine study eligibility, participants responded to demographic questions. This included their biological sex, gender, sexual orientation, age, race/ethnicity, relationship status, and state, county, and zip code of current residence (location information was used to calculate the different levels of Gini scores).

Next, participants responded to a variety of questions and statements about items related to income inequality. Most of these items are modeled on measures from prior studies (Gimpelson & Treisman, 2017; Norton & Ariely, 2011). Participants were asked to indicate their own income in $10,000 increments, ranging from $0 to over $100,000. Then, participants were asked questions about their current job, job social status, job paying status, layoffs, economic recessions, wealth redistribution, wealth hoarding, the gap between the rich and poor, poverty rates, and income distribution. Finally, participants were asked to indicate which of the five income distribution patterns for societies (Fig. 1) best describes their country’s income inequality. This question is aimed at directly assessing how people perceive the income distribution of the United States, with type A being the most inequal and type D being the most equal.

After the income inequality questions, participants responded to items assessing their numerical literacy. These items included the 8-item Subjective Numeracy Scale (SNS), developed by Fagerlin et al. (2007). Examples of the scale’s questions are, “How good are you at working with fractions?” The SNS showed good reliability in this sample (McDonald’s ω = 0.843), with a mean of 4.01 and standard deviation of 1.00. Two new exploratory items to measure numerical literacy were also asked, which asked participants to estimate how long it would take to count to a million, to a billion, and to a trillion. The responses to these items, however, proved to be so diverse as to be unusable (e.g., the range of responses for counting to a million was from 40 min to 30 years) and are therefore not included in these analyses.

Participants then responded to the intrasexual competition questions, based on the work of Olson et al. (2020) on mate presence and intrasexual competition. Participants were instructed to imagine they were single and were actively looking for a sexual or romantic partner. Then, they were given the following vignette:

It’s the biggest party of the year, and you know you can’t miss it! You’re really excited because your crush said they were going to the party and mentioned meeting up there. You promised your friend that you would go to the party with them. You aren’t really sure who is going to attend the party, so you and your friend are planning on staying with each other for most of the night.

Participants then rated how they would like to dress at that party on a slider from 0 (modest) to 100 (provocative) utilizing the pictures from Keys and Bhogal (2016, see their Supplemental materials) as visual endpoints.

Utilizing items derived from Fletcher et al. (2004), participants were then asked to rate the extent to which a potential “crush” would value the traits of warmth (Trustworthiness, Understanding, Supportive), resources (Status, Successful, Financially Stable), and physical attractiveness (Attractiveness, Sexiness, Active/Healthy). Each trait was rated on a seven-point Likert scale from extremely unimportant to extremely important. Items for all three traits showed acceptable reliability in this sample (McDonald’s ω = 0.885, 0.748, and 0.734, respectively), with means of 4.69–6.08 and standard deviations of 0.897–1.10.

Finally, participants responded to the Intrasexual Competition Scale (ICS), developed by Buunk and Fisher (2009). The ICS aims to gauge the degree of animosity or negativity women feel about other women when it comes to competing for romantic partners and in other general situations, such as work. Examples of the scale’s questions are, “I like to be funnier and more quick witted than other women,” and, “When I am at a party, I enjoy it when men pay more attention to me than other women.” The ICS showed good reliability in this sample (McDonald’s ω = 0.911), with a mean of 2.52 and standard deviation of 1.08. Finally, participants then responded to another attention check and were given an opportunity to leave any questions or comments about the study. They were debriefed about the study, which included additional resources and contact information, and thanked for their participation. The data and R code for analyses are available at: https://osf.io/ku4ha/.

Results

The intrasexual attitudes hypothesis predicts that women with greater perceived levels of income inequality will have significantly more negative attitudes toward other women, indicating greater intrasexual competition. Two simultaneous regressions were run; per Albert et al. (2022), the intrasexual competition scale was split into two subcomponents: Inferiority Frustration and Superiority Enjoyment. Each regression utilized the intrasexual competition measure as the target variable, with different measures of income inequality as potential predictor variables (i.e., state Gini, county Gini, zip code Gini, and Perceived [Five Societies] inequality). The omnibus model test for the Inferiority Frustration subscale revealed no significant predictors (F(4, 640) = 1.46, p = .214, Adjusted R2 = 2.8e−3). Importantly, collinearity statistics also found that the income inequality predictor variables, which are conceptually related, did not present collinearity issues (VIF 1.00–1.28; Tolerance 0.78–1.00). The regression predicting the Superiority Enjoyment subscale similarly revealed a null omnibus test (F(4, 640) = 0.67, p = .615, Adjusted R2 = 2.1e−3). A full table of these results can be seen in Tables S1 and S2 in the ESM.

The suggestive dressing hypothesis predicts that women with greater perceived levels of income inequality will be significantly more likely to endorse themselves dressing suggestively. A simultaneous regression was run with self-sexualizing scores as the target variable, and with different measures of income inequality as potential predictor variables (as listed above). The omnibus model test revealed a significant relationship (F(4, 640), = 4.87, p < .001, Adjusted R2 = 0.02), which was driven by perceived inequality (t = 2.78, p = .005) and county-level Gini (t = 2.53, p = .012). A full table of these results can be seen in Table S3.

The desirable traits hypothesis predicts that women with greater perceived levels of income inequality will rate physical appearance traits significantly higher in importance. A simultaneous regression was run with physical trait importance scores as the target variable, and with different measures of income inequality (as listed above) as potential predictors. The omnibus model test revealed no significant predictors (F(4, 640), = 1.97, p = .098, Adjusted R2 = 5.8e−3). A full table of these results can be seen in Table S4.

Additional simultaneous regressions were conducted to further explore predictors of self-sexualization and of perceived income inequality. The first analysis aimed to evaluate the ability of age, relationship status, and partner traits importance (physical attractiveness, resources, and warmth) to predict self-sexualizing scores. The overall model was significant, (F(10, 686), = 14.16, p < .001, Adjusted R2 = 0.15), with significant predictors of age (t = − 7.47, p < .001) and physical attractiveness as an important partner trait (t = 6.23, p < .001). Additionally, relationship status predicted self-sexualization such that those who had been widowed reported significantly lower self-sexualization (t = − 2.09, p = .037). A full table of these results can be seen in Tables S5 and S6.

A second exploratory simultaneous regression examined variables that might predict perceived income inequality as measured by the Five Societies scale (the strongest measure of income inequality that was itself predictive of self-sexualization in the form of clothing choice). The overall model was significant (F(16, 628), = 6.18., p < .001, Adjusted R2 = 0.11). Of the potential predictors of state Gini, county Gini, zip code Gini, personal income range, perceptions of 1% of wealth owners, own income status perceptions, perceptions of poverty rates, and perceptions of income gap, four were significantly predictive. These four were perceptions of 1% wealth owners (t = 3.27, p = .001), poverty rate perception (t = 2.92, p = .003), one’s own income status (t = − 2.32, p = .021), and income gap perception, such that those who believed the income gap had increased had a significantly greater estimate of income inequality (t = 3.42, p < .001). The complete results can be seen in Tables S7 and S8. The data and R code, for both analyses and assumption checks, are available at: https://osf.io/ku4ha/.

Discussion

A question we aimed to investigate was how income inequality at three different levels (state, county, & zip code Gini) affects women’s intrasexual competition. This included examining whether income inequality predicts intrasexual attitudes and behaviors, whether people are utilizing true or perceived income inequality as cues, and which cues of income inequality individuals are utilizing, if any.

The female intrasexual attitudes hypothesis predicted that greater perceived levels of income inequality by women will predict significantly more negative attitudes toward other women through intrasexual competition. None of the three levels of income inequality measured (state, county, and zip code) or perceived inequality showed a significant relationship with negative attitudes toward other women.

The suggestive dressing hypothesis predicted that greater income inequality will be associated with women being significantly more likely to endorse themselves dressing suggestively, and this did receive some support. Both county Gini and perceived inequality were significant predictors of self-sexualizing in hypothetical outfit choice. The results of this analysis suggest that women may be most closely tracking income inequality subjectively and on a more local level. As noted earlier, this type of result could be due to women tracking their immediate environments more so than larger regional or national ones. Proximate assessments of inequality would be both more computationally feasible as a process, more feasible as an evolved adaptation, and could also contribute to understanding the apparent discrepancy between perceived inequality and (national level) statistics such as the Gini index.

The desirable traits hypothesis, that greater income inequality will lead women to rate physical appearance traits significantly higher in importance, was not supported. As with the measure of female intrasexual attitudes, it seems that income inequality may have more easily measurable influences on intrasexual competition behaviors rather than intrasexual competition attitudes. A summary of the results can be found in Table 1.

Table 1.

Results summary by hypothesis

Hypothesis Data used Outcome
The female intrasexual attitudes hypothesis: Greater perceived levels of income inequality will be associated with women having more negative attitudes toward same-sex others. Actual income level (state, county, and zip code), perceived income inequality, and the intrasexual competition scale (split into two subcomponents). No significant predictors; hypothesis not supported.
The suggestive dressing hypothesis: Greater perceived levels of income inequality will be associated with women being more likely to endorse themselves dressing suggestively. Actual income level (state, county, and zip code), perceived income inequality, and self-sexualizing scores. County income level and perceived inequality were significant predictors; hypothesis somewhat supported.
The desirable traits hypothesis: Greater perceived levels of income inequality will be associated with women rating physical appearance traits significantly higher in importance. Actual income level (state, county, and zip code), perceived income inequality, and physical trait importance scores. No significant predictors; hypothesis not supported.
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Exploratory regression analyses found that younger age and physical trait importance were also significant predictors of women’s tendencies to dress more suggestively. This finding may be particularly notable because the current participant sample (from mTurk) had a wider age range representation than some prior studies (e.g., Blake et al., 2018; Keys & Bhogal, 2016). This broader representation provides valuable context for other studies that relied on college-aged participants, for whom there may be some context and age-specific factors that limit the visibility of these variables as predictors of behavior.

A second exploratory analysis found that perceptions of income inequality (as measured by the Five Societies Gini) was significantly predicted by perceptions of how much wealth the 1% of wealthiest people have, poverty rate, income gap, personal income status (which includes several other factors, but not actual Gini indices), and the perception that the income gap had increased in recent years. These results suggest that societal perceptions and beliefs about income, wealth, and standard of living—whether they are accurate or not—significantly predict one’s perception of national income inequality. Those who believe that there is less equity between the rich and the poor naturally believe there is more income inequality. This suggests that it is not actual income inequality levels that are influencing perceptions of income inequality, but rather individuals’ perceptions of how they (and others) stand relative to the very poor and very wealthy.

These results suggest that people, generally, are not accurate at estimating income inequality because it is based on personal perceptions of how well-off people are doing. A process such as this could lead to someone who is well-off being more likely to think a greater number of people are in their income group than there truly are (i.e., underestimate inequality), while simultaneously leading someone much less well-off to also believe more people are in their income group than there are (also thus underestimating income inequality). More abstractly, this is a process of individual people, in the presence of incomplete and subjective information, filling the gaps in their knowledge with more of the same information they already have. Because that information is biased by local homogeneity the true level of diversity is not recognized.

Limitations

One major limitation of the current study could be that the participant sample was limited to those in the United States. Although this allowed for greater control and consistent data across participants, it also is the case that Gini index data across geographic levels can be fairly similar to each other. For example, a resident of El Paso County, Texas (zip code 79901), had a state Gini of 0.477, a county Gini of 0.467, and zip code Gini of 0.461. The similar values can make it difficult to differentiate at which specific level people could be tracking income inequality. As it turns out, though, these Gini indices are not multicollinear and in fact are only moderately correlated (r = .165–.464). The overall lack of relationship between measures of income inequality and negative attitudes toward other women suggests that women might not be utilizing income inequality as a cue to their attitudes toward other women or differential weight placed on physical attractiveness. Some recent research has advocated for methods of measuring inequality that do not rely on the Gini coefficient as a way to resolve these issues (Blesch et al., 2022).

An alternative possibility one might consider is that participants could be utilizing a national income inequality baseline, which would be the same across all of the present participants (e.g., 0.415). This seems to be an implicit position in some prior research on income inequality, yet it raises several issues. First, how could individuals perceive a broad and diffuse statistic such as national income inequality based on their lived experience? Second, why would individuals use national level inequality when it turns out that more local measures are not as correlated as one might think and are also more relevant to their lives? Finally, the use of a national income inequality baseline would leave totally unresolved the question about how people are both reacting adaptively to national inequality and simultaneously unable to estimate that inequality accurately.

Another possible limitation in the present research is the measurement of intrasexual competition. While the ICS has been used as an outcome variable in previous research (e.g., Arnocky et al., 2014), it is more typically used as a trait measure of intrasexual competition attitudes rather than a state measure of changes to intrasexual strategy. However, because income inequality is a long-term, steady measurement of differential access to economic resources, we expected that it would influence the development of more trait-like attitudes rather than specific intrasexual strategies used.

Additionally, the more state-like clothing choice measure, which captures more state-like behavioral changes to intrasexual strategy, is targeted toward young adult women rather than capturing the range of intrasexual competition strategies that may be used by a variety of ages. Future research should include additional measures of strategies, such as derogation of competitors and self-promotion tactics.

Future Directions

Based on the present findings on perceived income inequality, future research should further seek to determine how well individuals actually perceive income inequality, if at all, and how other perceptions might impact intrasexual attitudes and behaviors. Additionally, personal perceptions of national-level standards of living, wealth, and income earnings were found to be strong predictors of perceptions of income inequality and warrant more in-depth examination. Additional research with these variables, as well as experimental manipulation, could shed more light onto how people perceive their economic environment, how accurate they truly are on all these aspects, and how they contribute to perceived income inequality. Other effects in our study that seemed to be strong were age and societal beliefs, specifically based on wealth and income.

The replicated result here of a relationship between female self-sexualization and perceived/county-level income inequality is an important refinement of the original result (Blake et al., 2018; Blake & Brooks, 2019a, b). It is also important, though, to follow up on the relationships not found here as they suggest limitations to these and prior findings.

Conclusion

The present study found little evidence that broad-level income inequality is driving intrasexual competition, sharply limiting some previous research results (Blake et al., 2018; Blake & Brooks, 2019b). It is possible that these collective results could be due to covariates of income inequality in the environment. For example, cities tend to have higher income inequality than rural areas (Bishaw & Posey, 2016) and cities also have more online female self-sexualization (e.g., sexy selfie postings) simply because of base rates: more people live in cities and thus more people from cities can self-sexualize. Additionally, it seems that age plays a significant role in this relationship with intrasexual competition, which has not been thoroughly represented in previous research.

Understanding complex relationships with correlational data—often the main source of data available given preexisting societal systems—is always difficult. Our best guess based on the present results is that perceptions of specific aspects of society (wealth of the top 1%, poverty rate, and own income/income gap) feed into overall perceptions of income inequality, rather than some type of internalized Gini index. That perception of subjective income inequality, in turn, has some influence on female self-sexualization behaviors but not on broader attitudes toward other women.

Supplementary Material

Supplementary Material

Acknowledgements

This research was supported by a Doreen Shanteau undergraduate research fellowship to AMR, from the Department of Psychological Sciences, Kansas State University.

Biographies

Abby M. Ruder is a graduate of Kansas State University, receiving a Bachelor of Science in psychology and a Bachelor of Science in economics in 2022. She will be pursuing a master’s degree in economics at New Mexico State University in 2024. Her research interests include judgment and decision-making, female intrasexual competition, behavioral economics, and personality decisions.

Gary L. Brase is a professor and interim department head in the Department of Psychological Sciences at Kansas State University. He studies complex human decision making using social, cognitive, and evolutionary theories. His research includes work on topics such as medical decisions, decisions about sustainability issues, relationship and fertility decision making, personality and mating decisions, and reasoning about social rules.

Nora J. Balboa is a graduate student in the Department of Psychological Sciences at Kansas State University. Her research focuses on social decision making across contexts such as mating, emotional judgments, and reciprocally altruistic scenarios. All aim to provide a better understanding of the interplay of social relationships and judgment strategies present when making decisions.

Jordann L. Brandner is an assistant professor in the Department of Psychology at Elon University. Her research integrates evolutionary, cognitive, and social psychology to understand the judgment and decision-making processes that underly relationship decisions such as mate choice and interpersonal attraction. Her work includes projects on perceiving and communicating sexual interest, tracking environmental sex ratios, and the cognitive processing of mate value.

Sydni A. J. Basha is a graduate research assistant and NIDA T32 Pre-Doctoral Fellow in the Department of Psychology at Arizona State University. Her current research primarily centers around understanding how clinical practitioners influence participant engagement with trauma-informed, evidence-based interventions. In her prior work, she was interested in understanding how individuals make decisions about romantic relationships and understanding individual differences in perceptions of mate value and sociosexual orientation.

Footnotes

Declarations

Competing Interests The authors all declare that they have no financial or non-financial interests that are directly or indirectly related to this work.

Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s12110-023-09466-y.

Data Availability

The data and R code for analyses are available at https://osf.io/ku4ha/.

References

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplementary Material
NIHMS1970155-supplement-Supplementary_Material.pdf (147.5KB, pdf)

Data Availability Statement

The data and R code for analyses are available at https://osf.io/ku4ha/.

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