Rank, stress, and risk: A conjecture.

A perception at the core of studies that consider the link between social rank and stress (typically measured by the so-called stress hormone cortisol) is that the link is direct. Examples of such studies are Bartolomucci (2007), Beery and Kaufer (2015), and Koolhaas et al. (2017). A recent and stark representation of this body of work is a study by Smith-Osborne et al. (2023), who state that "social hierarchies directly influence stress status" (Smith-Osborne et al. p. 1537, italics added). In the present paper, we reflect on this "direct" perspective. We conjecture that the link between social rank and stress involves an intervening variable: an indirect relationship arises when the loss of rank triggers a behavioral response in the form of risk taking aimed at regaining rank, and it is the engagement in risk-taking behavior that is the cause of an elevated level of cortisol. Smith-Osborne et al., as well as others whose papers are cited by Smith-Osborne et al. and who, like Creel (2001) and Avitsur et al. (2006), conducted comprehensive research on the association between rank (social standing) and stress, do not refer to risk taking at all. We present four strands of research that lend support to our conjecture: evidence that in response to losing rank, individuals are stressed; evidence that in response to losing rank, individuals resort to risk-taking behavior aimed at regaining their lost rank; evidence that there exists a link between engagement in risky activities or exposure to risk and elevated levels of cortisol; and an analytical perspective on incidence and intensity, namely a perspective that shows how the willingness to take risks responds to a change in rank, specifically, how a loss of rank triggers a greater willingness to take risks and how this trigger is stronger for individuals whose rank is higher.

The modification of social space as a tool for lowering social stress.

The social stress experienced by an individual from having a low relative income or from having a low income-based rank is a derivative of the individual's location in social space, and is the outcome of unfavorable comparisons with other individuals in that space. (The term social space stands for the set of individuals with whose incomes or with whose income-based ranks the individual compares his income or his income-based rank.) The stress that arises from unfavorable social comparisons can cause physical and mental harm. Essentially, there are three ways to thwart unfavorable income-related comparisons experienced by an individual: to operate on the individual's income or on a characteristic (an attribute) of the individual's income; to operate on the incomes or on a characteristic of the incomes of the individual's comparators; or to modify the individual's social space. The first two approaches feature extensively in the existing literature. The third does not. In this communication, I analyze this third approach, keeping in mind its application as a policy tool for lowering social stress.

"COVID-19 and income inequality in OECD countries:" A methodological comment.

Wildman (2021), who identifies "a clear association between income inequality [measured by the Gini coefficient] and COVID-19 cases and deaths," concludes that "a goal of government should be to reduce [income] inequalities and [thereby] improve [the COVID-19 outcomes /] underlying health of their populations." In this Comment, we argue that reducing the Gini coefficient of the income distribution of a population need not weaken the population's social stress. It is this stress which is a source of adverse health outcomes of the population. Because a measure of this stress is a component of the Gini coefficient, reducing the coefficient can leave the measure as is, or even increase the measure.

On a tendency in health economics to dwell on income inequality and underestimate social stress.

Social stress can cause physical and mental harm. It is therefore not surprising that public health policy makers have sought to identify and implement policies aimed at tackling this social ill. A frequently prescribed remedy is to reduce social stress by reducing income inequality, which is typically measured by the Gini coefficient. Decomposing the coefficient into a measure of a population's social stress and a population's income makes it possible to show that steps taken to lower the coefficient can actually exacerbate social stress. We formulate conditions under which lowering the Gini coefficient coincides with increasing social stress. If the aim of public policy is to improve public health and increase social welfare, and if social welfare is reduced by social stress, then lowering the Gini coefficient may not be the right course of action.

Menopause as a regulatory device for matching the demand for children with its supply: A hypothesis.

Drawing on two assumptions: that menopause is an instrument for the efficient regulation of the duration of a biologically expensive state, and that people have children in order to obtain support from them in old age, we set out a new idea that seeks to explain both the occurrence of menopause and its timing. On the basis of the notion that the purpose of having children is to obtain support in old age, we perceive menopause as an upper limit to the fertile state, when a continued ability to give birth to children would not generate the desired support. The conjecture yields specific testable predictions, and can be assessed against the "reproductive conflict" hypothesis. Being supported by one's offspring is a distinctive feature of humans; in this context, we cannot rely on animal studies in evolutionary biology and related fields to help us to ascertain something that is specific to humans.

"Reexamining the Influence of Conditional Cash Transfers on Migration From a Gendered Lens": Comment.

In a recent article, "Reexamining the Influence of Conditional Cash Transfers on Migration From a Gendered Lens," Hughes (2019) claimed that conditional cash transfers, CCT, limit the likelihood of migration by women, compensating them for giving up an attractive migration option. I question the analysis that lies behind this claim. I argue that in seeking to understand the likelihood of women migrating if they participate in a CCT program, issues of selectivity, endogeneity, and optimization cannot be set aside. In particular, it is not that receiving CCT curtails a migration option; it is that not contemplating migration encourages women to accept CCT. And if a household perspective is brought to bear, then a household's free choices weaken the appeal of migration to women. This reduction in appeal does not arise from an exogenously imposed curb but rather from endogenously determined preferences.

A methodological rejoinder to "Does income relate to health due to psychosocial or material factors?"

There is a presumption that when an individual's comparison of his income with the incomes of others in his comparison group yields an unfavorable outcome, the individual is dismayed and experiences stress that impinges negatively on his health. In a recent study, Hounkpatin et al. (2016) conduct an inquiry aimed at deciphering which measure of low relative income reflects better the adverse psychosocial effect of low relative income on health. Hounkpatin et al. pit against each other two indices that they characterize as "competing:" the "relative deprivation (Yitzhaki Index)" of individual i, RDi; and the "income rank position" of individual i, Ri. In this Rejoinder we show that because a measure of rank is embodied in the RDi index and the Ri index can be elicited from the RDi index, these two indices need not be viewed as competing. Furthermore, we formulate a composite measure of relative deprivation, CRDi, which can be used to assess more fully the psychosocial effect of individual i's low relative income on his health.

Is population growth conducive to the sustainability of cooperation?

This paper asks whether population growth is conducive to the sustainability of cooperation. A simple model is developed in which farmers who live around a circular lake engage in trade with their adjacent neighbors. The payoffs from this activity are governed by a prisoner's dilemma "rule of engagement." Every farmer has one son when the population is not growing, or two sons when it is growing. In the former case, the son takes over the farm when his father dies. In the latter case, one son stays on his father's farm, whereas the other son settles around another lake, along with the "other" sons of the other farmers. During his childhood, each son observes the strategies and the payoffs of his father and of the trading partners of his father, and imitates the most successful strategy when starting farming on his own. Then mutant defectors are introduced into an all-cooperator community. The defector strategy may spread. A comparison is drawn between the impact in terms of the sustainability of cooperation of the appearance of the mutants in a population that is not growing, and in one that is growing. It is shown that the ex-ante probability of sustaining the cooperation strategy is higher for a community that is growing than for a stagnant community.