Academic journal article Perception and Psychophysics

Inverted-U Effects Generalize to the Judgment of Subjective Properties of Faces

Academic journal article Perception and Psychophysics

Inverted-U Effects Generalize to the Judgment of Subjective Properties of Faces

Article excerpt

Researchers studying absolute identification have long known that it takes more time to identify a stimulus in the middle of a range than one at the extremes. That is, there is an inverted-U relation between mean response time and response position. In this task, an inverted-U relation also exists between response uncertainty and response position. Similarly, an inverted-U relation between mean response time and response position has been found for psychometric measures involving questions about the self. However, psychophysicists explain these inverted-U effects differently than do self-schema researchers. We propose an integrative framework in which task constraints explain these effects. To verify the generality of these inverted-U effects, we hypothesized that they would exist in three tasks having similar constraints-in this case, tasks involving the judgment of subjective properties of faces on a Likert-type scale. Our results are consistent with this hypothesis. We discuss the relevance of the results for other applications of Likert-type scales.

(ProQuest: ... denotes formula omitted.)

Researchers from several disciplines have found that participants make judgments more quickly at the extremes of a set of ordered response categories than in the middle. In other words, there is an inverted-U relation between mean response times (RTs) and response position. This inverted-U RT effect has been identified in domains as diverse as absolute identification (Brown, Marley, Donkin, & Heathcote, 2008; Monahan & Lockhead, 1977) and psychometric tests (Akrami, Hedlund, & Ekehammar, 2007; Casey & Tryon, 2001; Catanzaro, 1997; Crandall, 1998). In an absolute identification task, each participant makes judgments of a physical property of stimuli, such as the length of a bar. The inverted-U RT effect describes the fact that participants take less time to judge the shortest and longest bars of the range. In the psychometric tests in which the inverted-U RT effect has been found, participants are typically asked to evaluate how much they agree with a given statement about themselves, using a Likert-type scale. In this context, the inverted-U RT effect describes the fact that participants respond faster when they strongly agree or strongly disagree with a statement. In absolute identification, researchers have also found a related effect, that the diversity of responses provided for a stimulus, or response uncertainty, is less for stimuli at the extremes than for those in the middle of the presented range (Avant, Bevan, & Wing, 1968; Behar, 1963). We call this effect an inverted-U response uncertainty effect. Similarly, in the field of psychometrics, many researchers have remarked that there is greater ambiguity in the middle of Likert-type scales than at the extremes (e.g., Coolican, 1994; Weems & Onwuegbuzie, 2001).

Psychophysicists (Brown et al., 2008; Lacouture & Marley, 1995; Monahan & Lockhead, 1977; Stewart, Brown, & Chater, 2005) explain these inverted-U effects differently than do self-schema researchers (Akrami et al., 2007; Casey & Tryon, 2001; Catanzaro, 1997; Crandall, 1998; Kuiper, 1981). Self-schema researchers usually explain them by a two-process mechanism whereby judgments about the self activate a process different from that involved in the judgment of unfamiliar others. Psychophysicists attribute the inverted-U effects to stimulus representation and response selection processes. Here, we adopt the psychophysical perspective by testing an integrative framework in which inverted-U effects are part of a general phenomenon that arises in any task of judging stimuli on a response scale involving polytomous (i.e., more than two) ordered categories.

As detailed in the next section, every successful contemporary model of choice in unidimensional absolute identification-and, when included, RT-involves a unidimensional representation of the relevant stimulus attribute, followed by some form of limited capacity mapping of that stimulus representation to a response selection phase. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.