Emotions before actions: When children see costs as causal.

Adults expect people to be biased by sunk costs, but young children do not. We tested between two accounts for why children overlook the sunk cost bias. On one account, children do not see sunk costs as causal. The other account posits that children see sunk costs as causal, but unlike adults, think future actions cannot make up for sunk costs. These accounts make opposing predictions about whether children should see sunk costs as affecting emotions. Across three experiments, 4-7-year-olds (total N = 320) and adults (total N = 429) saw stories about characters who collected items that were easy or difficult to obtain, and predicted characters' emotions and actions. At all ages, participants anticipated that characters would feel sadder about high-cost objects, but only adults predicted that characters would keep high-cost objects. Our findings show that children see incurred costs as causal, and that costs are integrated children's and adults' theory of emotions. Moreover, the findings suggest that developmental differences in sunk cost reasoning may rest in children's incomplete mental accounting. We also discuss children's reasoning about rational and irrational action.

Close counterfactuals and almost doing the impossible.

Can we feel that an unrealized outcome nearly happened if it was never possible in the first place? People often consider counterfactual events that did not happen, and some counterfactuals seem so close to reality that people say they "almost" or "easily could have" happened. Across four preregistered experiments (total N = 1,228), we investigated how judgments of counterfactual closeness depend on possibility, and whether this varies across two kinds of close counterfactuals. In judging whether outcomes almost happened, participants were more strongly impacted by possibility than by incremental manipulations of probability. In contrast, when judging whether outcomes easily could have happened, participants treated the distinction between impossible and possible like any other variation in probability. Both kinds of judgments were also impacted by propensity, though these effects were comparatively small. Together, these findings reveal novel differences between the two kinds of close counterfactuals and suggest that while possibility is privileged when judging what almost happened, probability is the focus when judging what easily could have happened.

Calculated Feelings: How Children Use Probability to Infer Emotions.

Developing the ability to accurately infer others' emotions is crucial for children's cognitive development. Here, we offer a new theoretical perspective on how children develop this ability. We first review recent work showing that with age, children increasingly use probability to infer emotions. We discuss how these findings do not fit with prominent accounts of how children understand emotions, namely the script account and the theory of mind account. We then outline a theory of how probability allows children to infer others' emotions. Specifically, we suggest that probability provides children with information about how much weight to put on alternative outcomes, allowing them to infer emotions by comparing outcomes to counterfactual alternatives.

Local or foreign? Flexibility in children's preference for similar others.

Children have a robust social preference for people similar to them, like those who share their language, accent, and race. In the present research, we show that this preference can diminish when children consider who they want to learn about. Across three experiments, 4- to 6-year-olds (total N = 160; 74 female, 86 male, from the Waterloo region in Canada, a predominantly White and middle-class region) and adults (N = 103) saw pairs of characters. One character was from nearby and had characteristics typical of the participating child's location (e.g., playing soccer), whereas the other character was from far away and had characteristics atypical of children's location (e.g., playing hurling). In Experiment 1, children had no preference when judging who they liked better, but preferred foreign characters when judging who they wanted to learn about. Experiments 2 and 3 followed up by using procedures where participants were not told anything about the characters besides whether they were local or foreign. Children and adults preferred local characters when choosing who they liked, but preferred local characters less when choosing who to learn about. These findings show that children's preferences for similar others are flexible and depend on the judgment they are making. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Two kinds of counterfactual closeness.

People often consider counterfactual events that did not happen, and some counterfactuals seem so close to actual events that they are described as aspects of reality. In five preregistered experiments (N = 1,195), we show there are two kinds of counterfactual closeness. These two kinds of closeness are inferred from different causes, elicit different emotions, and are described using different linguistic expressions. Distance-based closeness is inferred from the distance between the counterfactual and reality, is expressed by saying the counterfactual almost happened, and is more strongly linked with disappointment than surprise. Meanwhile, odds-based closeness is inferred from prior odds, is expressed by saying the counterfactual easily could have happened, and is more strongly linked with surprise. Even without information about the distance between outcomes and prior odds, people more strongly link expressions of whether something almost happened with disappointment and link expressions of whether something easily could have happened with surprise. In sum, counterfactual closeness is not perceived on a single dimension. Instead, there are at least two forms of closeness. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Probability and intentional action.

How does probability affect attributions of intentionality? In five experiments (total N = 1410), we provide evidence for a probability raising account holding that people are more likely to see the outcome of an agent's action as intentional if the agent does something to increase the odds of that outcome. Experiment 1 found that high probability without probability raising does not suffice for strong attributions of intentionality. Participants were more likely to conclude a girl intentionally obtained a desired gumball from a single gumball machine when it offered favorable odds for getting that kind of gumball compared with when it offered poor odds, but their attributions of intentionality were lukewarm. Experiments 2 and 3 then found stronger attributions of intentionality when the girl raised her probability of success by choosing to use machines offering favorable odds over machines offering poor odds. Finally, Experiments 4 and 5 examined whether these effects of probability raising might reduce to consideration of agents' beliefs and expectations. We found that although these mental states do matter, probability raising matters too-people attribute intentional actions to agents who increase their odds of success, rather than to agents who merely become convinced that success is likely. We discuss the implications of these findings for claims that control and skill contribute to attributions of intentional action.

The social network: How people infer relationships from mutual connections.

People infer that individuals are socially related if they have overlapping preferences, beliefs, and choices. Here we examined whether people also infer relationships by attending to social network information. In five preregistered experiments, participants were shown the social networks of two target people and their friends or acquaintances within a group, and judged if the targets were socially related to one another. In the first three experiments, adults (total N = 528) were more likely to judge that individuals were friends when a high rather than low proportion of their friendships were mutual. Adults also considered other factors when inferring friendships, such as the number of friends each individual had. In the final two experiments, 5-7-year-olds (total N = 135) were also sensitive to the proportion of mutual relationships. Together, our work suggests that people use proportional information and statistical inferences when assessing whether individuals are socially related. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The odds tell children what people favor.

In pursuing goals, people seek favorable odds. We investigated whether young children use this fact to infer goals from people's actions across two experiments on Canadian 3- to 7-year-old children (N = 316; 167 girls, 149 boys). Participants' demographic information was not formally collected, but the region is predominantly middle-class and White. In Experiment 1, 3-year-old children saw a story where one agent went to a gumball machine with mostly red gumballs and another agent went to a machine with mostly purple ones. When asked which agent wanted a red gumball, children mostly selected the agent who chose the mostly red machine. Moreover, children responded at chance in a control condition where they judged which agent knew they would get a red gumball. In Experiment 2a, 3- to 7-year-old children saw a story where an agent either chose between two gumball machines or two open bowls of gumballs. In both conditions, the agent chose a location with mostly red gumballs over one with mostly blue gumballs but ended up with a blue gumball. Children were more likely to infer the agent had wanted a red gumball when the agent had made a probabilistic choice (machines) than a determinative choice (bowls), though inferences that the red gumball was preferred also increased with age. In Experiment 2b, a preregistered follow-up, American adults responded similarly to the older children. Together our findings suggest that children infer goals by drawing on the understanding that people seek favorable odds, though the clearest findings come from children aged 6 years and older. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Novelty preferences depend on goals.

People are sometimes drawn to novel items, but other times prefer familiar ones. In the present research we show, though, that both children's and adults' preferences for novel versus familiar items depend on their goals. Across four experiments, we showed 4- to 7-year-olds (total N = 498) and adults (total N = 659) pairs of artifacts where one was familiar and the other was novel (e.g., a four-legged chair and ten-legged chair). In Experiment 1, children wanted to have familiar artifacts, but to learn about novel ones. Experiment 2 replicated this pattern using a simpler procedure, and found the same pattern in adults. In Experiment 3, 4- to 6-year-olds and adults more strongly preferred familiar items when choosing which they would rather have than when choosing which they would rather try using. Finally, Experiment 4 replicated adults' preferences to have familiar items and learn about novel ones with an additional set of items. Together these findings show that preferences for novelty depend on people's goals. We suggest these effects arise because children and adults are motivated both by the promise of information and the desire for safe options in high commitment decisions that entail risk.

Young children's use of probabilistic reliability and base-rates in decision-making.

Children are skilled reasoners who readily use causal, reliability, and base-rate (i.e., prior probability) information in their decisions. Though these abilities are typically studied in isolation, children often must consider multiple pieces of information to make an informed decision. Four experiments (N = 320) explored the development of children's ability to use reliability and base-rate information when making decisions about draw outcomes. Experiment 1 examined the age at which children can first compare and choose between probabilistically reliable machines. Three- and 4-year-old children saw machines that were probabilistically reliable at obtaining objects while sampling from uniform distributions (i.e., all target or non-target objects). Although 4-year-old children correctly used reliability in their decisions, 3-year-olds did not. In Experiment 2a, 4- to 6-year-olds were presented with the same probabilistically reliable machines, although they sampled from a mixture of target and non-target items. Here, children tended to choose the machine with the better proportion of targets, regardless of reliability. This was replicated in Experiment 2b. In Experiment 3, children were presented with one perfectly reliable machine and one probabilistically unreliable machine. Here, children continued to mostly choose the machine with the better proportion of targets. These results raise questions about base-rate overuse early in development and highlight the need for additional work on children's ability to use multiple pieces of information in decision-making.

Developmental change in the use of base-rates and individuating information.

Adults tend to make biased inferences when they are given base-rates (i.e., prior probabilities) that conflict with individuating information (i.e., a personality description), relying heavily on individuating information. Recent work has shown that six-year-olds do the same, whereas four-year-olds rely more on prior probabilities. In the present article, we revisit the argument that producing responses that align closely with base-rates should necessarily be seen as normative. We instead posit that rational inferences should be sensitive to all relevant information and should depend on its strength. In three experiments, we explored four-year-olds', six-year-olds' (N = 200), and adults' (N = 196) information use by manipulating the strength of individuating and base-rate information. Across base-rate manipulations, adults showed a bias for individuating information regardless of its strength. In contrast, six-year-olds appeared to use each type of information flexibly, depending on which was more informative. Four-year-olds' performance was less clear: Although they relied on base-rates when they were informative, they struggled to use the individuating information in their inferences and did not appreciate the manipulation of the strength of individuating information. Thus, six-year-olds appear to more flexibly use multiple sources of information than both younger children and adults, suggesting a period in development where children are able to weigh information before they are too biased toward individuating information. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Blind to Bias? Young Children Do Not Anticipate that Sunk Costs Lead to Irrational Choices.

Young children anticipate that others act rationally in light of their beliefs and desires, and environmental constraints. However, little is known about whether children anticipate others' irrational choices. We investigated young children's ability to predict that sunk costs can lead to irrational choices. Across four experiments, 5- to 6-year-olds (total N = 185) and adults (total N = 117) judged which of two identical objects an agent would keep, one obtained at a high cost or one obtained at a low cost. In Experiment 1, adults predicted that the agent would choose the high-cost object over the low-cost one, whereas children responded at chance. Experiment 2 replicated these findings in children, but also included another condition which showed they were sensitive to future costs. They predicted that an agent would be more likely to seek out a low-cost item than a high-cost item. Experiments 3 and 4 then found that children do not anticipate the sunk cost bias in first person scenarios, or in interpersonal sunk cost scenarios, where costs are sunk by others. Taken together, our findings suggest that young children may struggle to understand and predict irrational behavior. The findings also reveal an asymmetry between how they consider sunk costs and future costs in understanding actions. We propose that this asymmetry might arise because children do not consider sunk costs as wasted.

Oh so close! Children's close counterfactual reasoning and emotion inferences.

How we feel about an outcome often depends on how close an alternative outcome was to occurring. In four experiments, we investigated whether predominantly White, middle-class, Canadian children (N = 425, Experiments 1-3) and American adults (N = 227, Experiment 4) consider close counterfactual alternatives when inferring other people's emotions. In Experiment 1, 6-year-olds (but not 4- and 5-year-olds) inferred that an agent would feel sadder about winning a mediocre prize if she later found out that a more attractive one could have easily been won. However, children of all ages failed to judge whether the better outcome could have easily happened. In Experiment 2, when 5- and 6-year-olds knew the locations of the prizes beforehand, they inferred that an agent would be equally happy about winning a mediocre prize, regardless if she almost won a better prize or not. Again, they did not recognize when the better outcome was a close counterfactual possibility. In Experiment 3, we included extra cues to the closeness of the alternative and both 5- and 6-year-olds inferred that she would feel sadder about winning a mediocre prize, and 6-year-olds acknowledged that the attractive prize was a close counterfactual alternative. In Experiment 4, adults considered close counterfactuals when inferring emotions. Our findings suggest that close counterfactuals influence children's emotion inferences before they become able to acknowledge their closeness. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Components and Mechanisms: How Children Talk About Machines in Museum Exhibits.

The current investigation examines children's (N = 61; 4- to 8-year old) learning about a novel machine in a local history museum. Parent-child dyads were audio-recorded as they navigated an exhibit that contained a novel artifact: a coffee grinder from the turn of the 20th century. Prior to entering the exhibit, children were randomly assigned to receive an experimental "component" prompt that focused their attention on the machine's internal mechanisms or a control "history" prompt. First, we audio-recorded children and their caregivers while they freely explored the exhibit, and then, we measured children's learning by asking them two questions in a test phase. Children of all ages, regardless of the prompt given, discussed most aspects of the machine, including the whole machine, its parts, and, to a lesser extent, its mechanisms. In the test phase, older children recalled more information than younger children about all aspects of the machine and appeared more knowledgeable to adult coders. Overall, this suggests that children of all ages were motivated to discuss all aspects of a machine, but some scaffolding may be necessary to help the youngest children take full advantage of these learning opportunities. While the prompts did not significantly influence the number of children who discussed the machine's mechanisms, children who received the component prompt were rated as more knowledgeable about the machine in the test phase, suggesting that this prompt influenced what they learned. Implications for visitor experience and exhibit design are discussed.

Toddlers and Preschoolers Understand That Some Preferences Are More Subjective Than Others.

Four experiments examined Canadian 2- to 3-year-old children's (N = 224; 104 girls, 120 boys) thoughts about shared preferences. Children saw sets of items, and identified theirs and another person's preferences. Children expected that food preferences would be more likely to be shared than color preferences, regardless of whether the items were similar or different in appeal (Experiments 1-3). A final study replicated these findings while also exploring children's expectations about activity and animal preferences. Across all studies, children expected shared preferences at surprisingly low rates (never higher than chance). Overall, these findings suggest that young children understand that some preferences are more subjective than others, and that these expectations are driven by beliefs about domains of preferences.

Infants' reasoning about samples generated by intentional versus non-intentional agents.

The current experiments investigate how infants use goal-directed action to reason about intentionally sampled outcomes in a probabilistic inference paradigm. Older infants and young children are flexible in their expectations of sampling: They expect random samples to reflect population statistics and non-random samples to reflect an agent's preferences or goals (Kushnir, Xu, & Wellman, 2010; Xu & Denison, 2009). However, more recent work shows that probabilistic inference comes online at approximately 6 months (Denison, Reed, & Xu, 2013; Kayhan, Gredebäck, & Lindskog, 2017; Ma & Xu, 2011; Wellman, Kushnir, Xu, & Brink, 2016), and thus, these sampling assumptions can be investigated at the age probabilistic reasoning first emerges. Results indicate that 6-month-old infants expect a human agent to sample in accord with their goal and do not expect the same of an unintentional agent-a mechanical claw. By 9.5 months, infants expect the mechanical claw to sample in accord with random sampling. These results suggest that infants use goals to make inferences about intentional sampling, under appropriate conditions at 6 months, and they have expectations of the kinds of samples a mechanical device should obtain by 9.5 months.

Who knows what? Preschoolers appreciate the link between ownership and knowledge.

We investigated 4- and 5-year-olds' (N = 194) appreciation of the link between knowledge and ownership. Namely, we asked whether preschoolers appreciate the ways in which owners are typically knowledgeable about artifacts. Experiment 1 revealed that 4- and 5-year-olds view owners as better sources of knowledge about artifacts than those who simply like artifacts. Experiment 2 built on these findings by showing that 5-year-olds appreciate that owners typically have deep knowledge about artifacts and that they can use this appreciation to guide inferences about who owns what. These experiments are some of the first to investigate how children's inferences about knowledge and ownership are intertwined. As such, they have implications for our understanding of early childhood cognition. First, they provide insights into how object-person relations influence judgments of expertise. Second, they extend current understandings of ownership by demonstrating that ownership influences preschoolers' reasoning in other domains (i.e., knowledge) and by showing that preschoolers' theories of ownership extend beyond normative considerations (i.e., ownership rights). Together, these findings lay the groundwork for a new area of work on how ownership influences children's reasoning about knowledge. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Exploring information use in children's decision-making: Base-rate neglect and trust in testimony.

Classic literature in judgment and decision-making shows that when testimony information conflicts with base-rates, adults typically underuse base-rate information and rely heavily on testimony (Bar-Hillel, 1980; Lyon & Slovic, 1976; Tversky & Kahneman, 1981). Although children can use base-rates (Denison, Konopczynski, Garcia, & Xu, 2006; Kushnir, Xu, & Wellman, 2010) and testimony (Koenig & Harris, 2005) separately in their inferences, whether they show a similar tendency toward weighing testimony more heavily is unknown. Four- and 5-year-old children were asked to guess the color of a dog's collar, drawn from a group of 10 dogs (e.g., 8 blue: 2 yellow). Children were also presented with testimony about the dog's collar that was from either a previously accurate or inaccurate witness. In Experiment 1 (N = 120), children were presented with only base-rate or testimony information. They relied on base-rates at above chance levels and relied on testimony at rates that approximately matched the witness's previous accuracy. In Experiment 2 (N = 160), when base-rates and testimony were presented together and conflicted, a majority of children endorsed the color consistent with the accurate witness's testimony, neglecting base-rates. However, when presented with the inaccurate witness's testimony, children were more likely to endorse the color indicated by the base-rates. Children appear to rely on the testimony of an accurate but fallible witness, revealing that a tendency to neglect base-rates in favor of testimony emerges early in development, yet they remain sensitive to the witness's accuracy when presented with multiple sources of information. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Young Children Use Probability to Infer Happiness and the Quality of Outcomes.

Happiness with an outcome often depends on whether better or worse outcomes were initially more likely. In five experiments, we found that young children (N = 620, Experiments 1-4) and adults (N = 254, Experiment 5) used probability to infer emotions and assess outcome quality. In Experiments 1 and 2, 5- and 6-year-olds (but not 4-year-olds) inferred that an agent would be less happy with an outcome if a better outcome were initially more likely. In Experiment 3, 4- to 6-year-olds used probability to assess quality. These findings suggest a developmental lag between 4-year-olds' assessments of quality and happiness. We replicated this lag in Experiment 4. In Experiment 5, adults used probability to assess both quality and happiness. We suggest that children and adults may use probability to establish a standard against which actual outcomes are compared. Doing so might allow them to make probability-based inferences of happiness without drawing on counterfactual reasoning.

Infant Statisticians: The Origins of Reasoning Under Uncertainty.

Humans frequently make inferences about uncertain future events with limited data. A growing body of work suggests that infants and other primates make surprisingly sophisticated inferences under uncertainty. First, we ask what underlying cognitive mechanisms allow young learners to make such sophisticated inferences under uncertainty. We outline three possibilities, the logic, probabilistic, and heuristics views, and assess the empirical evidence for each. We argue that the weight of the empirical work favors the probabilistic view, in which early reasoning under uncertainty is grounded in inferences about the relationship between samples and populations as opposed to being grounded in simple heuristics. Second, we discuss the apparent contradiction between this early-emerging sensitivity to probabilities with the decades of literature suggesting that adults show limited use of base-rate and sampling principles in their inductive inferences. Third, we ask how these early inductive abilities can be harnessed for improving later mathematics education and inductive inference. We make several suggestions for future empirical work that should go a long way in addressing the many remaining open questions in this growing research area.