Christian Unkelbach

University of Cologne | UOC · Department of Psychology

We argue that one reason why people consider others’ ideological beliefs (i.e., progressive vs. conservative) is that people profit by predicting others’ exploration behavior from their beliefs. Eight experiments confirmed that people more readily invested in progressives when switching to novel options (i.e., exploration) was more profitable than...

Evaluative conditioning (EC) is the change of a conditioned stimulus’s evaluation due to its pairing with an unconditioned stimulus (US). While learning typically shows negativity biases, we found no such biases in a reanalysis of meta-analytic EC data. We provide and test a cognitive-ecological answer for this lack of negativity bias. We assume th...

Serial judgments of different target persons in a given situation can depend on the target’s position in the series: Perceivers may initially withhold extreme judgments to avoid violating their judgment algorithm’s consistency in case of more extreme observations later on. With subsequent observations, perceivers may better calibrate their judgment...

Most psychological theories are expressed in natural language terms, which incurs a number of important problems (e.g., vagueness, limited refutability, lack of parsimony, possible contradictiveness, redundancy and specification gaps). Better theory specification has been called for many times, and formalization is a means of achieving it. We prese...

Fluency, defined as the metacognitive experience of ease, is a state that influences people's evaluations, judgments, and attitudes toward both others and themselves. Previous literature has explored various thematic aspects of fluency, ranging from smoothly deducing inferences to recognizing continuity and consistency in self-growth, and even to r...

In 2020, the Division of Social Psychology of the German Psychological Society (DGPs) published 11 methodological recommendations for improving the quality, replicability, and transparency of social psychological research. We evaluate these recommendations in a quantitative and qualitative survey conducted with members of the division (N = 54). Mos...

We apply the shared features principle to the domain of person perception: When one person (target) shares a feature with another person (source), people will make assumptions about various other features of the target. We tested this prediction by conducting three pre-registered studies (N = 695). Participants completed a training task wherein one...

People judge repeated information as truer than new information. In politics, this truth effect may be used to manipulate beliefs and evaluations of other politicians (e.g., by repeatedly derogating an opponent). We investigate the truth effect for such statements about others in political contexts. In two pre-registered experiments, we examined ho...

General Audience Summary The phenomenon that repetition increases the believability of both correct and incorrect information is well-established in the literature and of high societal relevance in today’s age of misinformation. Remarkably, research on this so-called truth-by-repetition effect largely neglected the reality that in today’s globalize...

We investigate how the complexity of the social environment (more vs. less groups) influences attitude formation. We hypothesize that facing a larger number of groups renders learning processes about these groups noisier and more regressive, which has two important implications. First, more-complex social environments should lead perceivers to unde...

Attribute conditioning refers to the phenomenon that target stimuli acquire specific attributes by pairing them with stimuli possessing these attributes. We apply attribute conditioning to a marketing context where brands are often displayed with stimuli possessing semantic attributes to establish brand-attribute associations. In particular, we exa...

We investigate self-appraisals over time using a cognitive–ecological approach. We assume that ecologically, negative person attributes are more diverse than positive ones, while positive person attributes are more frequent than negative ones. We combine these ecological properties with the cognitive process of similarity- and differences-based soc...

People judge repeated statements as more truthful than new statements: a truth effect. In three pre-registered experiments (N = 463), we examined whether people expect repetition to influence truth judgments more for others than for themselves: a bias blind spot in the truth effect. In Experiments 1 and 2, using moderately plausible and implausible...

People are more likely to believe information to be true if they have encountered it before. Research on this truth-by-repetition effect (TBRE) typically only considered one’s native language. In five experiments (N = 1344), we examined the TBRE in multi-lingual contexts (Belgium, Spain, US, Mexico). We found that the TBRE emerges in the non-native...

The first of three volumes, the five sections of this book cover a variety of issues important in developing, designing, and analyzing data to produce high-quality research efforts and cultivate a productive research career. First, leading scholars from around the world provide a step-by-step guide to doing research in the social and behavioral sci...

In serial evaluations (e.g., teachers evaluating student performances; managers evaluating job applications), people typically provide more extreme judgments at the end of a series compared to the beginning. Serial positions thereby represent an unwanted contamination of the judgment process; bad performances profit and good performances suffer fro...

Sampling approaches to judgment and decision making are distinct from traditional accounts in psychology and neuroscience. While these traditional accounts focus on limitations of the human mind as a major source of bounded rationality, the sampling approach originates in a broader cognitive-ecological perspective. It starts from the fundamental as...

We predicted and found in three experiments that psychological distance increases conceptual generalization. We manipulated psychological distance by describing a medicine as being either domestic (proximal) or foreign (distal) and examined generalization by testing how information about initial experience (positive vs. negative) with this medicine...

People judge repeated statements as more true than new statements: a truth effect. In three preregistered experiments (N = 463), we examined whether people predict others' truth judgments to be more biased by repetition than their own: a bias blind spot for the truth effect. In Experiment 1, using uncertain but moderately plausible statements, part...

People judge repeated information as truer than new information, a “truth-by-repetition” effect. Because repetition increases processing fluency, which is assumed to elicit positive affect, participants may match their positive experience associated with repeated information with a positive (“true”) rather than negative (“false”) response. We teste...

A key challenge for social psychology is to identify unifying principles that account for the complex dynamics of social behaviour. We propose psychological relativity and its core mechanism of comparison as one such unifying principle. To support our proposal, we review recent evidence investigating basic processes underlying and novel application...

Evaluative Conditioning (EC) research shows that people learn their likes and dislikes due to the co-occurrence of stimuli (CS and US) in the environment. Most recent EC research addressed processes underlying this phenomenon: how do people acquire their likes and dislikes? We address the question of when people learn from co-occurrences. To unders...

Past research indicates that people judge repeated statements as more true than new ones. An experiential consequence of repetition that may underly this “truth effect” is processing fluency: processing statements feels easier following their repetition. In three preregistered experiments (N=684), we examined the effect of merely instructed repetit...

Corneille et al. (2020) found that repetition increases judgments that statements have been used as fake news on social media. They also found that repetition increases truth judgments and decreases falsehood judgments (i.e., two instantiations of the truth-by repetition effect). These results supported an ecological explanation of the truth-by rep...

Moran et al. (2021) report a multi-lab registered replication of Olson and Fazio’s (2001) surveillance task. The surveillance task is an incidental learning procedure over the course of which participants observe pairings of conditioned stimuli (CSs) and unconditioned stimuli (USs) while engaging in a distracting secondary task. Unaware evaluative...

Guiding people’s attempts to sustain current states—from health and personal relationships, to households, jobs, and the biological environment—maintenance goals are a fundamental albeit understudied aspect of human motivation. We tested how comparisons to the self and to others impact the motivation to maintain. We hypothesized that maintenance go...

People believe repeated information more compared to novel information. Classic research on this repetition‐induced truth effect used trivia statements as information and truth ratings as the main DV. We investigate how repeating stereotypes about groups influence the stereotypes' believability and decisions about group members. Participants learne...

People rate and judge repeated information more true than novel information. This truth-by-repetition effect is of relevance for explaining belief in fake news, conspiracy theories, or misinformation effects. To ascertain whether increased motivation could reduce this effect, we tested the influence of monetary incentives on participants’ truth jud...

Corneille et al. (2020) found that repetition increases judgments that statements have been used as fake news on social media, a result that is consistent with an ecological theorization. They also found that repetition increases truth judgments and decreases falsehood judgments (i.e., two instantiations of the Truth-by-Repetition effect), which is...

Fluency is the experienced ease of ongoing mental operations, which increases the subjective positivity of stimuli attributes. This may happen because fluency is inherently positive. Alternatively, people may learn the meaning of fluency from contingencies within judgment-contexts. We test pseudocontingencies (PCs) as a mechanism through which flue...

In Dictator Games, dictators decide how much of a given endowment to send to receivers with no further interactions. We explored the social inferences people draw about dictators from the dictators’ money amount sent and vice versa in 11 experiments ( N = 1,425): Participants rated “unfair” dictators, who sent little or no money, as more agentic, b...

When judging whether someone is trustworthy, people rely on the perceptual typicality of a person’s face. We tested whether a more general typical-is-trustworthy heuristic exists based on the descriptive typicality of a person. In four experiments, we provided participants with descriptive information about the typicality of target persons’ attribu...

Past research indicates that people judge repeated statements as more true than new ones. An experiential consequence of repetition that may underly this “truth effect” is processing fluency: processing statements feels easier following their repetition. Here, we examine the effect of merely instructed (i.e., not experienced) repetition on truth ju...

People gather information about others along a few fundamental dimensions; their current goals determine which dimensions they most need to know. As proponents of competing social-evaluation models, we sought to study the dimensions that perceivers spontaneously prioritize when gathering information about unknown social groups. Because priorities d...

According to the evaluative information ecology model of social-comparison, people are more similar on their positive traits and tend to differ on their negative traits. This means that comparisons based on differences will naturally produce negative evaluations, whereas those based on similarities will produce positive evaluations. In this researc...

In a recent study, Shin and Niv explain both negativity and positivity biases in social evaluations as a function of the diversity and low frequency of events. We discuss why negative information is indeed more diverse and less frequent, and highlight the implications beyond social evaluations.

General Audience Summary The “truth effect” is the phenomenon that mere repetition increases belief in the repeated information, both relative to its initial presentation and relative to other, non-repeated information. This truth effect is currently recruited to explain how people come to believe apparently false information, which is a prominent...

Evaluative conditioning is one of the most widely studied procedures for establishing and changing attitudes. The surveillance task is a highly cited evaluative-conditioning paradigm and one that is claimed to generate attitudes without awareness. The potential for evaluative-conditioning effects to occur without awareness continues to fuel concept...

When people answer the question "How many animals of each kind did Moses take on the Ark?", they usually respond with "two," although Moses does not appear in the biblical story of the Ark. We investigated this "Moses illusion" in a multiple-choice format and tested the influence of monetary incentives on the illusion's strength. Thereby, we addres...

Moran et al. (2020) recently conducted a multi-lab registered replication of Olson and Fazio’s (2001) surveillance task study—an incidental learning procedure designed to establish evaluative conditioning (EC) effects in the absence of awareness. The potential for unaware attitude formation continues to fuel conceptual, theoretical, and applied dev...

Implicit measures are diagnostic tools to assess attitudes and evaluations that people cannot or may not want to report. Diagnostic inferences from such tools are subject to asymmetries. We argue that (causal) conditional probabilities p(AM+|A+) of implicitly measured attitudes AM+ given the causal influence of existing attitudes A+ is typically hi...

People believe repeated statements more compared to new statements – they show a truth by repetition effect. In three pre-registered experiments, we show that repetition may also increase perceptions that statements are used as fake news on social media, irrespective of the factual truth or falsehood of the statements (Experiment 1 & 2), but that r...

In attribute conditioning (AC), neutral stimuli (CSs) acquire specific attributes through mere pairings with other stimuli possessing that attribute (USs). For example, if a neutral person “Neal” is paired with athletic “Wade,” participants judge Neal as more athletic compared with when Wade would be unathletic. Building on Evaluative Conditioning...

As proponents of two theories of social evaluation, we disagree whether people spontaneously differentiate societal groups' conservative-progressive beliefs (distinct claim of the agency-beliefs-communion or ABC model) or warmth/communion (distinct claim of the stereotype content model or SCM). Our adversarial collaboration provides one way to reso...

Distinguishing between “good” and “bad” is a fundamental task for all organisms. However, people seem to process positive and negative information differentially, described in the literature as instances of negativity bias, positivity bias, or valence asymmetries. We provide an overview of these processing differences and their explanations. First,...

Measuring the similarity of stimuli is of great interest to a variety of social scientists. Spatial arrangement by dragging and dropping “more similar” targets closer together on the computer screen is a precise and efficient method to measure stimulus similarity. We present Qualtrics-spatial arrangement method (Q-SpAM), a feature-rich and user-fri...

Evaluative conditioning (EC) is one of the most widely-studied procedures for establishing and changing attitudes. The surveillance-task (Olson & Fazio, 2001) is a highly cited EC paradigm, and one that is claimed to generate attitudes without awareness. The potential for EC effects to occur without awareness continues to fuel conceptual, theoretic...

People often form attitudes about objects, individuals, or groups by examining and com-paring their attributes. Such attribute-based attitude formation is guided by a differentiation principle: Whether people come to like or dislike an attitude object depends on the object’s attributes that differentiate it from other objects. Attributes that are r...

People often form attitudes about objects, individuals, or groups by examining and comparing their attributes. Such attribute-based attitude formation is guided by a differentiation principle: Whether people come to like or dislike an attitude object depends on the object's attributes that differentiate it from other objects. Attributes that are re...

We propose the Evaluative Information Ecology (EvIE) model as a model of the social environment. It makes two assumptions: Positive “good” information is more frequent compared to negative “bad” information and positive information is more similar and less diverse compared to negative information. We review support for these two properties based on...

When a celebrity (e.g., George Clooney) endorses a brand (e.g., a coffee type), people’s assessment of this brand typically changes. We suggest that the mere repeated pairing of celebrities with brands imbues brands with the celebrities’ attributes. We call this effect attribute conditioning, which is, more generally, the phenomenon that people ass...

People are more inclined to believe that information is true if they have encountered it before. Little is known about whether this illusory truth effect is influenced by individual differences in cognition. In seven studies (combined N = 2,196), using both trivia statements (Studies 1-6) and partisan news headlines (Study 7), we investigate modera...

Generalisation in learning means that learning with one particular stimulus influences responding to other novel stimuli. Such generalisation effects have largely been overlooked within research on attitude acquisition via Evaluative Conditioning (i.e. EC effects). In five experiments, we investigated whether and when generalisation of EC effects i...

People are more inclined to believe that information is true if they have encountered it before. Little is known about whether this illusory truth effect is influenced by individual differences in cognition. In seven studies (combined N = 2196), using both trivia statements (Studies 1-6) and partisan news headlines (Study 7), we investigate moderat...

People believe repeated information more than novel information; they show a repetition-induced truth effect. In a world of “alternative facts,” “fake news,” and strategic information management, understanding this effect is highly important. We first review explanations of the effect based on frequency, recognition, familiarity, and coherent refer...

People judge positive information to be more alike than negative information. This good-bad asymmetry in similarity was argued to constitute a true property of the information ecology (Alves, H., Koch, A., & Unkelbach, C. (2017). Why good is more alike than bad: Processing implications. Trends in Cognitive Sciences, 21, 69–79). Alternatively, the a...

Processing fluency, the experienced ease of ongoing mental operations, influences judgments such as frequency, monetary value, or truth. Most experiments keep to-be-judged stimuli ambiguous with regards to these judgment dimensions. In real life, however, people usually have declarative information about these stimuli beyond the experiential proces...

We present a model of attribute conditioning, the phenomenon that people’s assessment of stimuli’s specific attributes (e.g., a person’s characteristics) changes due to pairings with other stimuli possessing these specific attributes (e.g., another "athletic" person). These changes in attribute assessments go beyond evaluation changes due to these...

People often hold negative attitudes toward out-groups and minority groups. We argue that such intergroup biases may result from an interaction of basic cognitive processes and the structure of the information ecology. This cognitive-ecological model assumes that groups such as minorities and out-groups are often novel to a perceiver. At the level...

The role of awareness in evaluative learning has been thoroughly investigated with a variety of theoretical and methodological approaches. We investigated evaluative conditioning (EC) without awareness with an approach that conceptually provides optimal conditions for unaware learning - the Continuous Flash Suppression paradigm (CFS). In CFS, a sti...

We investigate halo effects from agency behaviors and communion behaviors in different social contexts. According to the salient dimension model, attributes elicit halo effects on the ratings of other, unrelated attributes, when they are relevant in a situation. Given that communion behaviors are more relevant in social and care-related jobs, they...

People quickly form impressions about moral character; for example, if people learn that someone cheated, they form a negative impression about that person’s character and expect that person to cheat in the future. Four studies show that the formation of such moral character impressions depends on the degree of valence homogeneity in the target’s c...

People are more likely to judge repeated statements as true compared to new statements, a phenomenon known as the illusory truth effect. The currently dominant explanation is an increase in processing fluency caused by prior presentation. We present a new theory to explain this effect. We assume that people judge truth based on coherent references...

Positive attributes are more prevalent than negative attributes in the social environment. From this basic assumption, 2 implications that have been overlooked thus far: Positive compared with negative attributes are more likely to be shared by individuals, and people's shared attributes (similarities) are more positive than their unshared attribut...

Humans process positive information and negative information differently. These valence asymmetries in processing are often summarized under the observation that ‘bad is stronger than good’, meaning that negative information has stronger psychological impact (e.g., in feedback, learning, or social interactions). This stronger impact is usually attr...

Evaluative conditioning (EC) refers to changes in the evaluation of conditional stimuli (CSs; e.g., neutral faces) due to their repeated pairing with unconditional stimuli of positive or negative valence (USs; e.g., likeable or unlikeable faces). The standard EC finding is an assimilation effect; CS evaluations change in direction of US valence. In...

Previous research argued that stereotypes differ primarily on the 2 dimensions of warmth/communion and competence/agency. We identify an empirical gap in support for this notion. The theoretical model constrains stereotypes a priori to these 2 dimensions; without this constraint, participants might spontaneously employ other relevant dimensions. We...

Attribute Conditioning (AC) refers to people’s changed assessments of stimuli’s (CSs) attributes due to repeated pairing with stimuli (USs) possessing these attributes; for example, when an athletic person (US) is paired with a neutral person (CS), the neutral person is judged to be more athletic after the pairing. We hypothesize that this AC effec...

The density hypothesis (Unkelbach, Fiedler, Bayer, Stegmüller, & Danner, 2008) claims a general higher similarity of positive information to other positive information compared with the similarity of negative information to other negative information. This similarity asymmetry might explain valence asymmetries on all levels of cognitive processing....

Past research showed that people accumulate more knowledge about other people and objects they like compared to those they dislike. More knowledge is commonly assumed to lead to more differentiated mental representations; therefore, people should perceive others they like as less similar to one another than others they dislike. We predict the oppos...

We propose stronger halo effects in trait assessments from positive information relative to negative information. Due to positive information's higher similarity, positive information should foster both indirect (from a global impression to traits) and direct halo effects (from traits to traits). Negative information's relative distinctiveness shou...

Alcohol has been implicated in intergroup aggression and hostility. The effect of consuming alcohol relative to a placebo on hostile cognitive biases toward a social category typically stereotyped as threatening and hostile (i.e., Middle Eastern men) was tested. Undergraduates (N = 81) consumed either an intoxicating dose of alcohol (BrAC = .05% by...

When people rapidly judge the truth of claims presented with or without related but nonprobative photos, the photos tend to inflate the subjective truth of those claims-a "truthiness" effect (Newman et al., 2012). For example, people more often judged the claim "Macadamia nuts are in the same evolutionary family as peaches" to be true when the clai...

The density hypothesis states that positive information is more similar than negative information, resulting in higher density of positive information in mental representations. The present research applies the density hypothesis to recognition memory to explain apparent valence asymmetries in recognition memory, namely, a recognition advantage for...

Existing findings on the truth effect could be explained by recollection of the statements presented in the exposure phase. In order to examine a pure fluency account of this effect, we tested a unique prediction that could not be derived from recollection of a statement. In one experiment, participants judged the truth of a statement that had the...

People experience “regulatory fit” when they pursue a goal in a manner that suits their chronic regulatory orientation. This regulatory fit impacts performance positively. The present research extends performance gains due to fit from individuals to dyadic team performance. Study 1 manipulated team fit of 32 table football participants (i.e., promo...

In the context of research on human judgment, regression is commonly treated as an artifact or an unwanted consequence of ill-controlled research designs. We argue that this negative image is undeserved. Regression affords not only an enlightening statistical construct but also a theoretical construct that can inspire novel research. It offers alte...

Abstract We propose Attribute Conditioning (AC) as a form of learning that refers to changes in people's assessment of stimuli's (CSs) attributes due to repeated pairing with stimuli possessing these attributes (USs). We review the available evidence and based on this review, delineate three open questions and investigate them experimentally: a) th...

Serial evaluations are the basis of many judgment and decision processes (e.g., in sports, talent shows, or academic examinations). We address the advantages and disadvantages of being in the beginning or the end of such evaluation series. We propose that for serial evaluations, people must calibrate a transformation function that translates observ...

Attribute conditioning (AC) refers to people's changed assessment of stimuli's (conditioned stimuli, CSs) attributes due to pairings with stimuli possessing these attributes (unconditioned stimuli, USs). Up to now, research only showed conditioning of only one attribute within a conditioning session (e.g., athleticism) and measured assessment chang...

In this editorial, the editor looks back at the positive and negative developments at Social Psychology during the last year. In conclusion, the journal has implemented many changes within the last year (e.g., online submission, accepting replications, more content) but also kept many things constant (e.g., double-blind review, special issues). Soc...