Subliminal anchoring: Judgmental consequences and underlying mechanisms

Judgmental anchoring—the assimilation of a numeric estimate towards a previously considered standard—is an exceptionally ubiquitous effect that influences human judgment in a variety of domains and paradigms. Three studies examined whether anchoring effects even occur, if anchor values are presented subliminally, outside of judges’ awareness. Studies 1 and 2 demonstrate such subliminal anchoring effects: judges assimilated target estimates towards the subliminally presented anchor values. Study 3 further demonstrates that subliminal anchors produced a selective increase in the accessibility of anchor-consistent target knowledge. The implications of these findings for the ubiquity of judgmental anchoring, its different underlying mechanisms, and comparative information processing are discussed.     

The Semantics of Anchoring

Previous research has demonstrated that judgmental anchoring effects—the assimilation of a numeric estimate to a previously considered standard—are semantic in nature. They result because the semantic knowledge about the target object that is activated during the comparison with the anchor influences the absolute judgment. In addition to this semantic influence, the numeric anchor value itself may also yield an effect under specific conditions. The present research was designed to examine the relative strength of both mechanisms and explore their boundary conditions. Studies 1 and 2 demonstrate that semantic anchoring effects are more potent than purely numeric effects. Study 3 further suggests that purely numeric effects only operate if accessible semantic knowledge is inapplicable to the critical judgment so that semantic influences are incapacitated. The implications of these findings are discussed from the perspective of an integrative model which differentiates between two stages of anchoring. Whereas purely numeric influences appear to be limited to the stage of anchor selection, the actual comparison with the target involves more elaborate semantic processes.     

When knowledge matters—differential effects of available knowledge in standard and basic anchoring tasks

The present research examines whether anchoring effects—the assimilation of a numeric estimate towards a previously considered standard—depend on judges' available knowledge in the target domain. Based on previous research, I distinguish two types of anchoring effects. Standard anchoring is obtained if judges are explicitly asked to compare the anchor to the target. Basic anchoring results if the accessibility of the anchor is increased prior to judgments about the target. I expected that only basic but not standard anchoring is reduced by providing judges with judgment‐relevant knowledge. Using a standard versus basic anchoring paradigm, 112 participants were confronted with a high versus low anchor before estimating the average price of a German midsize car. Prior to this task, participants were provided with information about prices of cars (relevant knowledge) versus kitchens (irrelevant knowledge). Results demonstrate that this knowledge only influenced the magnitude of basic but not standard anchoring effects. This finding demonstrates that knowledge has differential effects in different types of anchoring. Copyright © 2007 John Wiley & Sons, Ltd.     

Taking the High (or Low) Road: A Quantifier Priming Perspective on Basic Anchoring Effects

ABSTRACT

Current explanations of basic anchoring effects, defined as the influence of an arbitrary number standard on an uncertain judgment, confound numerical values with vague quantifiers. I show that the consideration of numerical anchors may bias subsequent judgments primarily through the priming of quantifiers, rather than the numbers themselves. Study 1 varied the target of a numerical comparison judgment in a between-participants design, while holding the numerical anchor value constant. This design yielded an anchoring effect consistent with a quantifier priming hypothesis. Study 2 included a direct manipulation of vague quantifiers in the traditional anchoring paradigm. Finally, Study 3 examined the notion that specific associations between quantifiers, reflecting values on separate judgmental dimensions (i.e., the price and height of a target) can affect the direction of anchoring effects. Discussion focuses on the nature of vague quantifier priming in numerically anchored judgments.     

Are adjustments insufficient?

Many judgmental biases are thought to be the product of insufficient adjustment from an initial anchor value. Nearly all existing evidence of insufficient adjustment, however, comes from an experimental paradigm that evidence indicates does not involve adjustment at all. In this article, the authors first provide further evidence that some kinds of anchors (those that are self-generated and known to be incorrect but close to the correct answer) activate processes of adjustment, whereas others (uncertain anchors provided by an external source) do not. It is then shown that adjustment from self-generated anchors does indeed tend to be insufficient, both by comparing the estimates of participants starting from different anchor values and by comparing estimates with actual answers. Thus, evidence is provided of adjustment-based anchoring effects similar to the accessibility-based anchoring effects observed in the traditional anchoring paradigm, supporting theories of social judgment that rely on mechanisms of insufficient adjustment.     

The effect of global versus local processing styles on assimilation versus contrast in social judgment

The authors propose a global/local processing style model (GLOMO) for assimilation and contrast effects in social judgment. GLOMO is based on Schwarz and Bless' (1992, 2007) inclusion-exclusion model, which suggests that when information is included into a category, assimilation occurs, whereas when information is excluded from a category, contrast occurs. According to GLOMO, inclusion versus exclusion should be influenced by whether people process information globally or locally. In 5 experiments, using both disambiguation and social comparison, the authors induced local versus global processing through perceptual tasks and time perspective and showed that global processing produced assimilation, whereas local processing produced contrast. The experiments showed that processing styles elicited in one task can carry over to other tasks and influence social judgments. Furthermore, they found that hemisphere activation and accessibility of judgment-consistent knowledge partially mediated these effects. Implications for current and classic models of social judgment are discussed.     

The malleability of anchoring effects

Anchoring effects--the assimilation of a numeric estimate to a previously considered standard--are typically described as very robust and persistent. Based on the assumption that judgmental anchoring involves a hypothesis-testing process in which judges actively seek and generate judgment-relevant target knowledge, it was assumed that anchoring effects might at the same time be fairly malleable. Specifically, subtle influences that change the nature of the tested hypothesis are likely to affect the magnitude of anchoring. Using a procedural priming task, judges were induced to focus on similarities versus differences during a series of anchoring tasks. The results demonstrate that the magnitude of the obtained effect critically depended on this manipulation. In particular, a more pronounced anchoring assimilation effect resulted for judges with a similarity rather than a difference focus. Implications of these findings for models of anchoring as well as for the nature of the anchoring phenomenon are discussed.     

The need for contextual and technical knowledge in judgmental forecasting

The purpose of this research is to assess the extent to which judgmental forecasts are improved by having more contextual and technical knowledge. Contextual information is knowledge gained by practitioners through experience on the job, consisting of general forecasting experience in the industry as well as specific product knowledge. Technical knowledge is knowledge about data analysis and formal forecasting procedures, including information on how to analyze data judgmentally. We directly compared judgmental forecasts of business practitioners with those generated by students, using 22 real-world time series. The practitioners had considerable contextual but no technical knowledge. The students had no contextual but two different levels of technical knowledge. We also generated forecasts with statistical methods to benchmark performance. Results show that contextual knowledge is particularly important in making good judgmental forecasts, while technical knowledge has little value. Practitioner forecasts are better than student forecasts in almost all comparisons. A decisive factor affecting forecast performance appears to be data variability, measured by the coefficient of variation of the time-series data. As the variability of a time series increases, the performance of all forecasts deteriorates, but judgmental forecasts by practitioners become more preferable. Statistical methods have difficulty achieving reasonable forecasts when the data are more variable, whereas judgemental forecasts reinforced by contextual information do relatively well. Data variability is one explanation for the mixed findings of past studies, relative to how well statistical techniques compare with judgment as a forecasting method.     

Adaptive Anchoring Model: How Static and Dynamic Presentations of Time Series Influence Judgments and Predictions

When attempting to predict future events, people commonly rely on historical data. One psychological characteristic of judgmental forecasting of time series, established by research, is that when people make forecasts from series, they tend to underestimate future values for upward trends and overestimate them for downward ones, so‐called trend‐damping (modeled by anchoring on, and insufficient adjustment from, the average of recent time series values). Events in a time series can be experienced sequentially (dynamic mode), or they can also be retrospectively viewed simultaneously (static mode), not experienced individually in real time. In one experiment, we studied the influence of presentation mode (dynamic and static) on two sorts of judgment: (a) predictions of the next event (forecast) and (b) estimation of the average value of all the events in the presented series (average estimation). Participants' responses in dynamic mode were anchored on more recent events than in static mode for all types of judgment but with different consequences; hence, dynamic presentation improved prediction accuracy, but not estimation. These results are not anticipated by existing theoretical accounts; we develop and present an agent‐based model—the adaptive anchoring model (ADAM)—to account for the difference between processing sequences of dynamically and statically presented stimuli (visually presented data). ADAM captures how variation in presentation mode produces variation in responses (and the accuracy of these responses) in both forecasting and judgment tasks. ADAM's model predictions for the forecasting and judgment tasks fit better with the response data than a linear‐regression time series model. Moreover, ADAM outperformed autoregressive‐integrated‐moving‐average (ARIMA) and exponential‐smoothing models, while neither of these models accounts for people's responses on the average estimation task.     

锚定判断中的心理刻度效应：来自ERP的证据

当前主要有两种理论解释锚定效应的发生机制：锚定调整启发模型和选择通达模型。同样,锚值可能是自发产生的,也可能是外部提供的。本研究用两个ERP实验分别探讨了不同精细程度的心理刻度对自发锚定加工和外部锚定加工的影响。结果表明,只有在自发锚引起的锚定加工中才出现心理刻度效应：在目标呈现后250~800ms之间,精细心理刻度比粗糙心理刻度诱发一个更大的波形正走向,支持锚定调整启发模型。在外部锚引起的锚定加工中,没有出现心理刻度效应,却出现了一个与通达有关的N300成分,支持选择通达加工模型。总的结果支持了锚定加工的双重属性：锚定判断是主动调整还是选择通达取决于不同的情境     

Relatively certain! Comparative thinking reduces uncertainty

Comparison is one of the most ubiquitous and versatile mechanisms in human information processing. Previous research demonstrates that one consequence of comparative thinking is increased judgmental efficiency: comparison allows for quicker judgments without a loss in accuracy. We hypothesised that a second potential consequence of comparative thinking is reduced judgmental uncertainty. We examined this possibility in three experiments using three different domains of judgment and three different measures of uncertainty. Results consistently demonstrate that procedurally priming participants to rely more heavily on comparative thinking during judgment induces them to feel more certain about their judgment.     

Elaboration and consequences of anchored estimates: An attitudinal perspective on numerical anchoring

In the standard numerical anchoring paradigm, the influence of externally provided anchors on judgment is typically explained as a result of elaborate thinking (i.e., confirmatory hypothesis testing that selectively activates anchor-consistent information in memory). In contrast, theories of attitude change suggest that the same judgments can result from relatively thoughtful or non-thoughtful processes, with more thoughtful processes resulting in judgments that last longer over time and better resist future attempts at change. Guided by an attitudinal approach to anchoring, four studies manipulated participants’ level of cognitive load to produce relatively high versus low levels of thinking. These studies show that, although anchoring can occur under both high and low thought conditions, anchoring based on a higher level of thinking involves greater use of judgment-relevant background knowledge, persists longer over time, is more resistant to subsequent attempts at social influence, and is less likely to result from direct numeric priming.     

Sadness and susceptibility to judgmental bias: the case of anchoring

In a wide range of empirical paradigms, sadness has been associated with more extensive and detail-oriented thinking than happiness, resulting in reductions in judgmental bias that arise from reliance on stereotypes and other simple decision heuristics. It was hypothesized that anchoring would constitute a significant exception to this general pattern. Recent research on anchoring indicates that an active thought process underlies the emergence of this bias. If sad people are likely to think more actively about the judgmental anchor than their neutral-mood counterparts, their subsequent judgments should be more likely to be assimilated toward this reference point. This prediction was confirmed in two experiments demonstrating that sad people are indeed more susceptible to anchoring bias than are people in a neutral mood. Moreover, this effect generalized over judgments in positive, neutral, and negative content domains.     

Anchoring unbound

An attitudes and persuasion perspective can broaden our understanding of anchoring by highlighting sources of variability in anchoring effects that have been largely overlooked. As the target article suggests, research guided by this perspective can help identify (1) different types of anchors that exert their influence through different underlying mechanisms, 2) important social psychological moderators of anchoring effects, and 3) sources of variability in the consequences of anchoring for judgment and choice. In this commentary, we take an even broader perspective on the types of anchors that are likely to influence judgment, suggesting four potentially distinct types—intuitive approximations, best/worst case scenarios, environmental suggestions, and magnitude priming. We conclude by discussing how an attitudes and persuasion perspective on anchoring may provide novel insights into the moderators and consequences of anchoring effects in everyday life.     

Judgmental forecasts of time series affected by special events: does providing a statistical forecast improve accuracy?

Time series found in areas such as marketing and sales often have regular established patterns which are occasionally affected by exogenous influences, such as sales promotions. While statistical forecasting methods are adept at extrapolating regular patterns in series, judgmental forecasters have a potential advantage in that they can take into account the effect of these external influences, which may occur too infrequently for reliable statistical estimation. This suggests that a combination of statistical method and judgment is appropriate. An experiment was conducted to examine how judgmental forecasters make use of statistical time series forecasts when series are subject to sporadic special events. This was investigated under different conditions which were created by varying the complexity of the time series signal, the level of noise in the series, the salience of the cue, the predictive power of the cue information and the availability and presentation of the statistical forecast. Although the availability of a statistical forecast improved judgment under some conditions, the use the judgmental forecasters made of these forecasts was far from optimal. They changed the statistical forecasts when they were highly reliable and ignored them when they would have formed an ideal base‐line for adjustment. Copyright © 1999 John Wiley & Sons, Ltd.     

Uninformative Anchors Have Persistent Effects on Valuation Judgments

Anchoring effects influence a wide range of numeric judgments, including valuation judgments, such as willingness‐to‐pay (WTP). However, prior research has not established whether anchoring only temporarily distorts responses or exerts persistent influence on preferences. This article presents three incentive compatible experiments examining the long‐term effects of random anchoring on WTP. Study 1 evaluated the persistence of anchoring effects over long durations, and showed that the strength of the effect decayed but did not disappear completely even 8 weeks later. In Study 2, a random anchor significantly influenced WTP after one week, regardless of whether WTP was also elicited immediately following the anchoring procedure, showing that consistency motivations do not account for persistence of anchoring effects. Study 3 showed relatively low anchors resulted in more stable valuations, compared with participants who reported WTP with no anchoring procedure. Together with the pattern of decay over time in Study 1, this suggests that anchoring facilitates the “imprinting” of valuation judgments for later retrieval. These studies show that anchoring effects can lead to lasting changes in valuation judgments, providing the first demonstration of long‐term persistence of constructed preferences as a result of an uninformative and arbitrary manipulation.     

Modularity in everyday life judgments of aggression and violent behavior

This review focuses on one aspect of moral judgment of aggression and violent behavior in the context of the psychodynamics of everyday life: Judgmental modularity. The central hypothesis asserts that, from the victim's perspective, the severity of judgments or the relative weight assigned to physical damage, when information on intent and damage is available, will be maximized, whereas inverse trends will typify the judgments of the same person from the assailant's perspective. This view resembles the spirit of the functional approach to moral judgment of violent behavior. In this light, related studies that were conducted within the framework of functional measurement are reviewed. Judgmental modularity was documented in the majority of the findings. However, in two studies, the same participants exhibited judgmental consistency in the first phase and judgmental modularity in a second phase, which manipulated other types of judgmental perspectives. Implications for the issue of judgmental modularity, for the issue of modularity in violent behavior and for a proposal to establish a functional definition of aggression are discussed.     

Effects of time pressure on context-sensitive property induction

Past research suggests that category-based induction flexibly draws on different kinds of knowledge in different contexts, and that different kinds of knowledge may differ in accessibility. The present study investigates the degree to which knowledge accessibility mediates context-sensitive induction by examining the effects of time pressure on inferences about novel properties of animal species. Participants were told about a novel gene or a novel disease that was true of one category of animals, then rated the likelihood that taxonomically, ecologically, and unrelated animals had the same property, under speeded or delayed conditions. Property effects were observed for taxonomically related species independent of time pressure, but were only observed for ecologically related species in the delayed condition. These results suggest that time pressure selectively restricts access to ecological knowledge, and that knowledge access is critical for context-sensitive inductive reasoning.     

Improving judgmental forecasts with judgmental bootstrapping and task feedback support

This study examines the utility of two widely advocated methods for supporting judgmental forecasts—providing task feedback and providing judgmental bootstrapping support. In a simulated laboratory based experiment that focused on producing composite sales forecasts from three individual components, we compared the effectiveness of these two methods in improving final judgmental forecasts. In the presence of cognitive feedback task, feedback led to better forecasts than providing judgmental bootstrap forecasts. Simply providing bootstrap forecasts was of no additional benefit over a control condition. This was true in terms of the Brunswik Lens model measures of achievement, knowledge, and consistency, and in terms of forecast accuracy. This occurred both in stable environments and when special events (unusual one‐time events requiring adjustments to the forecasts) arose. Copyright © 2005 John Wiley & Sons, Ltd.     

Judgment processes in motivation: Anchoring and adjustment effects on judgment and behavior

The behavioral correlates of human judgment have received little attention from judgment and decision making researchers. One behavioral domain that provides for the study of judgment-behavior relations is task motivation (i.e., the allocation of time and effort to a task). Judgments of contingent relations are primary components of several theories of motivation, including expectancy theories and the theory of behavior in organizations proposed by Naylor, Pritchard, and Ilgen (1980). The characteristics of heuristic judgment processes are hypothesized to affect contingency judgments and thus behavioral allocations of time and effort. This paper examines the effects of the anchoring and adjustment heuristic upon (a) judgments of future effort and performance and (b) upon actual allocations of time and effort using several types of anchoring information. Results indicate that both irrelevant and relevant information have strong anchoring effects on effort and performance judgments, but do not have concomitant effects on behavior. Implications for the role of judgment in motivation and for the link between judgment and behavior are discussed.