Who incurs a cost for their group and when? The effects of dispositional and situational factors regarding equality in the volunteer's dilemma

Highlights

• In the volunteer's dilemma, at least one member must volunteer for the group.

• Those who respond negatively to suffering from inequality tend not to volunteer.

• Those who respond negatively to benefiting from inequality tend to volunteer.

• Those who have volunteered less than other members become more likely to volunteer.

• Those who have volunteered more than other members become less likely to volunteer.

Abstract

The “volunteer's dilemma” (VoD) is a group situation in which one member needs to incur a volunteering cost to provide public goods to the group. Considering that efficiency conflicts with equality in the VoD, we investigated how dispositional and situational variables regarding equality affect volunteering behavior in the VoD (specifically, in repeated VoD). We conducted an online VoD game comprising a new “lever-pulling paradigm,” and participants were grouped with two other participants to play the game iteratively. The results showed the effects of the dispositional factor (i.e., justice sensitivity; JS); those sensitive to suffering from inequality (i.e., those high in JS-Victim) were unlikely to volunteer, whereas those sensitive to benefiting from inequality (i.e., those high in JS-Beneficiary) were likely to volunteer. We also found the effect of the situational factor (i.e., previous relative volunteering rate); those who had volunteered more than others became less inclined to volunteer, and vice versa. This research shows that both dispositional and situational factors regarding equality play a crucial role in repeated VoD, while posing future questions and directions to understand their interaction effects.

Introduction

Imagine a work situation in which exactly one member of a project team is required to help the team manager. It is highly likely that everyone in the team would already have their hands full with their own tasks, so those who volunteer to undertake the additional task need to make sacrifices (e.g., personal time). Meanwhile, if no one was to volunteer, the project would fail to be completed in time, and this could adversely impact everyone's income. This group situation, in which one member needs to incur a cost to provide public goods to the group, can be referred to as the volunteer's dilemma (VoD; Diekmann, 1985). In the VoD, some members are inclined to volunteer for their group, while others are not. To understand what causes this difference in volunteering behavior, in the present research, we examined the effect of both dispositional (e.g., personality traits) and situational factors (e.g., others' behaviors), using an economic game experiment which involved financial incentives.

The VoD is a form of social dilemma; more precisely, it is a step-level public goods game of a group of n ≥ 2 players, in which public goods are provided only when at least one player incurs a volunteering cost. Here, n players simultaneously decide whether to volunteer or not. If no one decides to volunteer, no one gains anything—as Table 1 demonstrates. If at least one player chooses to volunteer (i.e., incurs a cost of c), each player receives a utility of b (where b > c > 0; i.e., the benefit of volunteering outweighs the cost).

In the VoD, it is most efficient to have only one member incurring a volunteering cost. This is because having more than one volunteer (“over-volunteering;” Krueger et al., 2016) does not improve the total gain; it only increases the total cost. Having no volunteer is also inefficient because, if no one volunteers, the payoff for each member is zero.

When a group faces the VoD only once (hereinafter, one-shot VoD), achieving efficiency concomitantly undermines equality (Tham, Hashimoto, & Karasawa, 2019). In the one-shot VoD, when only one group member volunteers (i.e., succeeds in providing public goods with the lowest cost), the volunteer gains a payoff of b – c, while each of the other members receives a payoff of b. Although achieving equality is possible if everyone/no one chooses to volunteer, both solutions entail inefficiency.

By contrast, it is possible to achieve both principles when a group repeatedly confronts the VoD (hereinafter, repeated VoD). In the repeated VoD, the person who volunteers gains a lower payoff (i.e., a payoff of b – c) than the other group members at some point. However, this person can, later on, let other members volunteer and enjoy a higher payoff (i.e., a payoff of b) than the volunteers, which is an efficient and equal solution. As Przepiorka et al. (2021) described, it is not rare for people to find themselves in a situation of the repeated VoD in everyday life. Consider the project team that we described in the first paragraph of this research. It is possible for a project team, in practical terms, to encounter a similar crisis (i.e., a situation in which they would miss the deadline if no one volunteers) more than once.

While most studies on the VoD have focused on the one-shot VoD (e.g., Feldhaus & Stauf, 2016; Hillenbrand & Winter, 2018; Kurz et al., 2018; Przepiorka & Diekmann, 2013), Diekmann and Przepiorka (2016) examined the emergence of conventions in the repeated VoD. They found that a group of people who faced the VoD for an indeterminate number of times tended to take turns to volunteer, which is an efficient and equal solution. Thus, people in the repeated VoD generally decide whether to volunteer depending on a previous relative volunteering rate (PRVR); those who have volunteered less than others become more inclined to volunteer, and vice versa. In the present research, in addition to being interested in this general tendency, we were also interested in individual differences in volunteering behavior. Specifically, we focused on justice sensitivity.¹

Although it has been said that, by and large, people prefer equality (Fehr & Schmidt, 1999; Shaw & Olson, 2012), it is also true that people differ in the strength of their preferences (Schmitt et al., 1995). To measure a personality trait that captures individual differences in perceptions of and reactions to injustice—including inequality—Schmitt et al. (2010) developed a self-reported measure called the Justice Sensitivity Inventory. This scale accounts for the fact that there can be four perspectives in a situation of injustice: of those who suffer from injustice (i.e., victims), of those who benefit from injustice (i.e., beneficiaries), of those who commit injustice (i.e., perpetrators), and of those who observe injustice (i.e., observers). In the scale, these four perspectives for justice sensitivity (hereinafter JS-Victim, JS-Beneficiary, JS-Perpetrator, and JS-Observer) are assessed separately.² When people are high in JS-Victim, JS-Beneficiary, JS-Perpetrator, or JS-Observer, they tend to show negative cognitive and emotional responses when becoming a victim, beneficiary, perpetrator, or observer, respectively, in a situation of injustice.

Previous studies have investigated the relationships between each kind of justice sensitivity and behavior in social dilemmas. In dictator games, those high in JS-Beneficiary, JS-Perpetrator, and JS-Observer were likely to divide money equally between themselves and one another, while those high in JS-Victim were not (Fetchenhauer & Huang, 2004). In prisoner's dilemma games, JS-Beneficiary positively correlated with cooperative behavior, while JS-Victim did not (Haesevoets et al., 2018). In public goods dilemma games, those high in JS-Beneficiary, JS-Perpetrator, and JS-Observer tended to contribute more to public goods (Schlösser et al., 2018). There was no significant effect of JS-Victim on contributing behavior in Schlösser et al. (2018), but another study showed that those high in JS-Victim became unlikely to contribute to public goods when they received cues of others' meanness (Gollwitzer et al., 2009). Overall, the literature shows that JS-Beneficiary, JS-Perpetrator, and JS-Observer have a positive effect on prosocial behavior, while JS-Victim does not. Further, some studies showed that those high in JS-Victim tend to display antisocial behavior (see also Gollwitzer et al., 2005).

Based on these studies, it is possible to infer that these effects of justice sensitivity may also appear in the VoD, not only because it is a form of social dilemma but also because it involves a trade-off between efficiency and equality. When people face such a trade-off and must choose whether to sacrifice equality for another principle, their preference for equality will play a crucial role in the choice. Indeed, Tham, Hashimoto, and Karasawa (2019) found that those high in JS-Victim were less willing to volunteer while those high in JS-Beneficiary were more willing to volunteer in the one-shot VoD. Note that this study analyzed only two kinds of justice sensitivity owing to the characteristics of the VoD; people in a group facing the VoD can only be either a “victim” (i.e., when they volunteer and receive a lower payoff than those who do not volunteer) or a “beneficiary” (i.e., when they do not volunteer and receive a higher payoff than those who volunteer), giving no space for a “perpetrator” or an “observer.”

Although the effects of justice sensitivity in the VoD have already been revealed by Tham, Hashimoto, and Karasawa (2019), this cited study included the following limitations. First, the researchers conducted only scenario-based experiments. In this regard, previous studies showed that there are discrepancies between decisions made in a hypothetical scenario and those made in a situation that involves some consequences (FeldmanHall et al., 2012; Teper et al., 2011). Thus, it is crucial to examine people's tendency to volunteer not only via self-report but also via real behavior. The second limitation is that the study examined only the one-shot VoD, so the effects of justice sensitivity in the repeated VoD remain unclear. In the one-shot VoD, equality conflicts with efficiency, which denotes that the extent to which people wish to avoid inequality can influence their volunteering intention and behavior. On the other hand, in the repeated VoD, efficiency and equality are compatible, so everyone may try to achieve both principles. Thus, while justice sensitivity is likely to affect intention and behavior in the former situation, it may not be the case in the latter situation.

The aim of the present research was to examine dispositional and situational factors regarding equality that can affect volunteering behavior in the repeated VoD. Furthermore, we explored interaction effects between the dispositional and situational factors. As to the situational factors, we aimed to conceptually replicate Diekmann and Przepiorka (2016), which found that, in the repeated VoD, people tend to take turns to volunteer, thereby allowing them to achieve both efficiency and equality. Generally, as noted above, this indicates that those who have volunteered less than others would become more inclined to volunteer, and vice versa. In the current research, we hypothesized that PRVR would have a negative effect on volunteering behavior (Hypothesis 1; hereinafter H1).

As to the dispositional factors, we examined the effects of justice sensitivity. As noted above, Tham, Hashimoto, and Karasawa (2019) have already found a negative effect of JS-Victim and a positive effect of JS-Beneficiary in the one-shot VoD. Although the influence of justice sensitivity might be smaller in the repeated VoD than in the one-shot VoD, we still hypothesized that JS-Victim would have a negative effect (Hypothesis 2; hereinafter H2) and JS-Beneficiary would have a positive effect on volunteering behavior (Hypothesis 3; hereinafter H3). This is because, even though people in the repeated VoD can simultaneously achieve efficiency and equality, we presumed that not all of them would try to do so unless being forced—and we did not provide a condition where they were forced to do so. In this case, there would be room for the dispositional factors to take effect.

To examine the effects of PRVR and justice sensiticity, we conducted an online experiment, in which participants were grouped with two other participants to play a VoD game repeatedly. This game involved financial incentives.