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PubMed1997

Informativity and asymmetry in comparisons.

We propose an account of comparison asymmetries based on viewing comparison as a process of structural alignment and mapping. Specifically, we hypothesize that (1) comparison asymmetries result from directional differences in informativity, and that (2) asymmetries can therefore be predicted from the relative degree of systematicity or conceptual coherence of the items being compared. In Experiment 1, we found a clear preference for placing the more systematic of two passages in the base position of a comparison. Experiments 1 and 2 further showed that structural alignability is crucial in obtaining such asymmetries. In Experiment 3, we found that asymmetries are predicted by the relative systematicity of the comparisons items rather than by the relative size of the distinctive feature sets. These results are inconsistent with accounts of asymmetry based on feature contrast or stimulus bias. In Experiments 4 through 6, we tested the functional implications of our account by examining inference projection and perceived informativity across asymmetric comparisons. Critically, comparisons having the more systematic item as the base were more likely to result in inference projection and other forms of target modification and were rated as more informative than reverse comparisons. We conclude by demonstrating that this account can explain comparison asymmetries without positing underlying asymmetries in subjective similarity, and that it offers a unified approach to the directionality of literal comparisons, analogies, and metaphors.

Adult↗

PubMed2001

The current status of microscopical hair comparisons.

Although the microscopical comparison of human hairs has been accepted in courts of law for over a century, recent advances in DNA technology have called this type of forensic examination into question. In a number of cases, post-conviction DNA testing has exonerated defendants who were convicted in part on the results of microscopical hair comparisons. A federal judge has held a Daubert hearing on the microscopical comparison of human hairs and has concluded that this type of examination does not meet the criteria for admission of scientific evidence in federal courts. A review of the available scientific literature on microscopical hair comparisons (including studies conducted by the Royal Canadian Mounted Police and the Federal Bureau of Investigation) leads to three conclusions: (1) microscopical comparisons of human hairs can yield scientifically defensible conclusions that can contribute to criminal investigations and criminal prosecutions, (2) the reliability of microscopical hair comparisons is strongly affected by the training of the forensic hair examiner, (3) forensic hair examiners cannot offer estimates of the probability of a match of a questioned hair with a hair from a randomly selected person. In order for microscopical hair examinations to survive challenges under the U.S. Supreme Court's Daubert decision, hair microscopists must be better trained and undergo frequent proficiency testing. More research on the error rates of microscopical hair comparisons should be undertaken, and guidelines for the permissible interpretations of such comparisons should be established. Until these issues have been addressed and satisfactorily resolved, microscopical hair comparisons should be regarded by law enforcement agencies and courts of law as merely presumptive in nature, and all microscopical hair comparisons should be confirmed by nuclear DNA profiling or mitochondrial DNA sequencing.

Expert Testimony↗

PubMed2002

Stability and inoculation of risk comparisons' effects under conflict: replicating and extending the "asbestos jury" study by Slovic et al.

Promotion or criticism of risk comparisons in risk communication has far exceeded empirical tests of their effects. Slovic et al. (1990) experimented with a hypothetical jury trial in which an asbestos-installing firm was accused of subjecting school occupants to unreasonable risk. A risk comparison sharply reduced subjects' estimates of risk and judgments that the firm was guilty, but a critique of the risk comparison had risk estimates and guilt judgments rebounding to the original (without risk comparison) level. Slovic et al. concluded that risk comparisons' effects were highly unstable, at least in conflict-ridden situations such as a jury trial. The present study replicates and extends this important study, using the same stimuli and questions. The respective effects of the risk comparison and the critique recurred, although much less sharply than in Slovic et al. Moreover, judgments of guilt, risk, and other aspects of the case seemed shaped more by demographics and beliefs about risk generically (e.g., about the likelihood of cancer after exposure to a carcinogen) than by either risk comparison or critique. A variant design, in which the defense's expert witness dismissed potential criticisms of the risk comparison, appeared to "inoculate" people against shifting their views after seeing the critique. Overall, these results show that risk comparisons might change some beliefs about risks in conflict and that "inoculation" can reduce vulnerability to criticism. However, the results also show strong limits on effects of both comparisons and their critiques: they shifted only a minority of judgments and had small effects relative to people's social locations and prior risk beliefs.

Adult↗

PubMed2005

Application of false discovery rate procedure to pairwise comparisons of refractive index of glass fragments.

This study was undertaken to apply a new method of controlling type I error when performing pairwise comparisons. The Benjamini and Hochberg false discovery rate (FDR) controlling procedures have proved to be very powerful tools in solving many practical problems but have not yet been applied to pairwise comparisons of refractive index of glass samples. Students t-test and Welch test (unequal variance Student's t-test) were applied to all possible pairwise comparisons. The comparisons were made on the basis of refractive index values of 72 glass fragments from different car windows and 69 different fragments from one windscreen. The type I error was controlled by the use of Benjamini and Hochberg false discovery rate (FDR) controlling procedure. To illustrate the importance of controlling type I error when using pairwise comparisons, results of pairwise comparisons with the FDR controlling procedure were compared to those comparisons made without any controlling procedure. Significantly fewer false negative results (false rejection of H0) were found during the use of FDR procedure in the comparison of refractive indices from the same windscreen than when comparing without controlling type I error. The results of application of FDR method were also compared to the results of other post-hoc tests, such as Tukey HSD test and Bonfferoni test. The FDR method has higher power than Bonferroni method and Tukey HSD method and control errors better than comparing without controlling type I error. The method of choice, for pairwise comparison of glass fragments on the basis of refractive index is Welch test with FDR adjustment. The method gave type I errors at level about 5.3% and type II error at about 3.7%.

Journal Article↗

PubMed2003

Status and solidarity in social comparison: agentic and communal values and vertical and horizontal directions.

Social comparison involves positioning the self relative to others on a vertical or status dimension (ranging from upward to downward comparisons) and a horizontal or solidarity dimension (ranging from contrastive to connective comparisons). Across 3 studies in which 389 undergraduates recorded everyday social comparisons (n = 4,417), downward and connective comparisons were rated as more helpful and mood enhancing than upward and contrastive comparisons. The effects of horizontal comparisons were greater for people for whom solidarity was an important value; however, the effects of vertical comparisons were not greater for people who valued status. The roles of the comparison target, topic, and situation were also explored; for example, noticing undesirable features of the target enhanced status but undermined solidarity.

Adolescent↗

PubMed1993

The role of social comparisons processes in the psychological adaptation of elderly adults.

Social comparison processes were investigated as mechanisms by which elderly women maintain or enhance their psychological well-being in the face of health-related threats or loss. In Study 1, a measure of social comparisons was tested, and a preliminary model of the effects of health and social comparisons on depression was examined (N = 42). In Study 2, a separate sample of elderly women (N = 243) completed self-report measures concerning physical health, upward and downward social comparison processes, and positive and negative aspects of psychological adaptation. As predicted, worse physical health status was linked to more frequent social comparisons; however, more positive social comparisons were related to better mental health outcomes, even for women in poor health. In fact, the effects of social comparisons were strongest for women in the poorest health, resulting in psychological outcomes similar to women in good health. Thus, social comparisons appear to play a significant role in psychological well-being in old age. The findings also point to the importance of distinguishing between frequency and consequences of social comparison processes.

Activities of Daily Living↗

PubMed2004

Varying risk comparison elements: effects on public reactions.

Expanding a limited empirical base on effects of risk comparisons, a pilot experiment explored how varying elements of such comparisons might influence public response. The scenario used was a hypothetical trial of an asbestos-installing firm for putting students and staff at a junior high school at "unreasonable risk," first used by Slovic et al. (1990). Study participants played the role of jurors in the trial, asked to rate the risk, the firm's guilt, whether it should be made liable for future health effects, whether the school should be occupied in its current condition, and whether the asbestos should be removed at a cost of 3 million dollars. Opportunity samples of New Jersey residents (n= 309) received information intended to vary four comparison attributes: number of dimensions of comparison; single versus multiple ways of expressing mortality; a narrative to explain and justify the risk comparison; and the hypothetical role of the participant (juror vs. parent). The dependent variable was a hazard scale constructed from four of the five postcomparison judgments. ANOVA found format variations swamped in their effect by concern about asbestos, with the absence of a narrative and the parental role being the only attributes that increased negative risk reactions. Multiple regression analyses found that multidimensionality, narrative, role, and the presence of any risk comparison at all had significant effects when these (plus death formats) were the only independent variables. However, only multidimensionality (which increased negative reactions) retained significance when asbestos concern, risk beliefs (no safe level of exposure to a carcinogen; any exposure leads to cancer), and demographic variables were added to the analysis. Concern and risk beliefs alone explained 33% of variance in hazard scores; adding demographics and risk comparison variables only raised explained variance to 36% (having children at home and being exposed to multidimensional risk comparisons raised scores; age and income lowered them). The results underline the potentially small effect of risk comparison information on risk views (at least between subjects), but offer some insight into aspects of message design left unexplored in empirical literature to date.

Journal Article↗

PubMed1995

Affective responses to social comparison: a study among disabled individuals.

The present study examined the effects of social comparison among 112 individuals receiving payments under the Disablement Insurance Act. A part of a fictitious interview with another disabled person was presented to the subjects. This interview contained upward or downward social comparison information about either the problem severity or coping success of a target. In line with the predictions, the results indicated that upward comparison generated more positive affect than downward comparison only for subjects high in perceived control. Downward comparison generated more negative affect than upward comparison, regardless of perceived control. The nature of the comparison dimension (problem severity versus coping success) did not result in differences in positive or negative affect. Furthermore, subjects high in control identified more strongly with the upward target than with the downward target, especially when the comparison dimension was coping success. Some evidence was found that the effect of perceived control on the positive affective consequences of upward comparison was mediated by identification with the upward target.

Adaptation, Psychological↗

PubMed2005

Paradoxical effects of praise and criticism: social, dimensional and temporal comparisons.

BACKGROUND: When developing a domain-specific academic self-concept, students are not restricted to social comparisons; they may also make temporal or dimensional comparisons. AIMS: The main purpose of this study was to examine whether these different types of comparison trigger paradoxical effects of praise and criticism in the sense described by Meyer (1992). University students participated in Study 1 (N=120) and Study 4 (N=83). The Study 2 sample consisted of 180 seventh to ninth grade students, and Study 3 investigated paradoxical effects with a sample of 130 elementary school students. METHODS: Participants were presented with vignettes describing the results of 2 students (social comparison condition) versus 1 student in 2 subjects (dimensional comparison) versus 1 student in 2 subsequent tests (temporal comparison). In all cases, the results were identical. Participants were then informed about a teacher's response to these results (praise vs. criticism vs. neutral response), and were asked to estimate the ability of the 2 stimulus persons. RESULTS: Study 1 and Study 2 revealed that dimensional, as well as social, comparisons following praise and criticism elicit paradoxical effects of perceived ability, reflected in corresponding estimations of student effort and teacher expectancies. There were no paradoxical effects following temporal comparisons. Study 3 did not reveal any paradoxical effects, thereby supporting the assumption that the occurrence of such effects depends on the level of cognitive development. Study 4 showed that the paradoxical effects found in Study 1 and 2 occur even when the sanctioned and the neutral achievement are presented independently. CONCLUSIONS: Dimensional comparisons, which have been largely overlooked in the past, play a major role in ability inferences.

Achievement↗

PubMed2006

Targets and dimensions of social comparison among people with spinal cord injury and other health problems.

The present research examined comparison targets and comparison dimensions among two Spanish samples of individuals facing serious illnesses and diseases. In Study 1, 90 older patients (mean age 66.36) with various age-related diseases, particularly cardiovascular diseases and diabetes, indicated that they compared themselves most often with others with the same disease, next with others with another disease and least with people without health problems. They compared themselves more often on their mental state, symptoms and physical activities than on their social activities. Social comparison orientation (SCO) as an individual difference characteristic was associated with more frequent comparisons with particularly similar targets, and with more frequent comparisons of one's symptoms and physical activities. Neuroticism was correlated only with more comparisons of one's symptoms. Study 2 was conducted in a sample of 70 relatively young patients (mean age 43.97) with spinal cord injury (SCI). Overall, they compared themselves more often with others than the participants in Study 1, and they compared themselves to a similar extent with people with SCI as with people with another disease and with people without health problems. While they felt on average better off than people with other diseases and other people with SCI, people with SCI felt on average worse off than people without health problems. They compared themselves more often on physical activities than on any other dimension. Higher levels of stress and uncertainty were associated with more frequent comparisons with people without SCI, and with more frequent comparisons of one's mental state, one's symptoms and one's future perspectives. The discussion focuses on the theoretical relevance of the results for social comparison theory, and on the practical relevance of the findings for interventions.

Aged↗

PubMed1989

Children's identity matching and oddity: assessing control by specific and general sample-comparison relations.

After children in Experiments 1 and 2 learned identity matching or oddity, control by sample-comparison relations was assessed. Tests for generalized control displayed novel samples and two comparison stimuli, one identical to the sample. Specific relations were tested with identical or nonidentical sample-comparison stimuli from one set of stimuli and substitute comparisons from either the other training set or from a novel set. When tests displayed identical stimuli, patterns of comparison selection suggested control by generalized identity and oddity. However, selection patterns varied when stimuli were nonidentical and familiar or novel substitute comparisons were used. Therefore, control by specific relations is not a precondition for generalized identity and oddity. One set of training stimuli was used in Experiment 3, and generalized performances occurred again. Moreover, control by specific relations was shown by the oddity subjects and 2 of 6 identity subjects. Generalized and specific control may therefore exist simultaneously. In Experiment 4, selections were irregular on tests displaying substitute comparisons and samples and familiar comparison stimuli; this finding supported the relational account of specific sample-comparison control found in Experiment 3.

Attention↗

PubMed2004

Group membership and everyday social comparison experiences.

In two everyday experience studies, we examined the degree to which everyday social comparisons are framed by group membership. In the first study, 30 undergraduates attending a public university in the United States completed short questionnaires about their social comparison experiences whenever they were signalled. In the second study, 34 ethnic minority undergraduates from the same university completed similar questionnaires about their social comparison experiences. Across both studies, comparisons in which participants viewed themselves as an ingroup member in comparison to an outgroup comprised less than 10% of the comparison experiences reported by participants. However, minorities in the second study who reported closer identification with their ethnic group reported more comparison experiences in which they mentioned their own or the comparison target's ethnicity.

Journal Article↗

PubMed2007

The comparison question test: does it work and if so how?

In a mock crime study of the comparison question test (CQT), 35 subjects decided to participate as guilty and 30 as innocent. Two conditions were varied: Explaining the comparison questions in the pretest interview and re-discussing comparison questions between charts. Higher identification rates (approximately 90% for guilty and innocent participants) were achieved in groups with explanation of comparison questions than in groups without explanation. Re-discussing comparison questions had no effect on identification rates. Ratings of subjective stress due to relevant and comparison questions were also obtained and can be seen as indicators of the significance of the questions. The significance of comparison questions was hardly affected by the different testing conditions. When effects are detectable at all, they contradict theoretical expectations in their direction. Results are discussed in terms of the significance of comparison questions used in polygraph testing.

Adult↗

PubMed1987

Impact of multiple comparisons in randomized clinical trials.

The randomized clinical trial is the preferred research design for evaluating competing diagnostic and therapeutic alternatives, but confidence in the conclusions from a randomized clinical trial depends on the authors' attention to acknowledged methodologic and statistical standards. This survey assessed the level of attention to the problem of multiple comparisons in the analyses of contemporary randomized clinical trials. Of the 67 trials surveyed, 66 (99 percent) performed multiple comparisons with a mean of 30 therapeutic comparisons per trial. When criteria for statistical impairment were applied, 50 trials (75 percent) had the statistical significance of at least one comparison impaired by the problem of multiple comparisons, and 15 (22 percent) had the statistical significance of all comparisons impaired by the problem of multiple comparisons. Although some statistical techniques are available, there still exists a great need for future work to clarify further the problem of multiple comparisons and determine how the impact of this problem can best be minimized in subsequent research.

Clinical Trials as Topic↗

PubMed1997

The results of direct and indirect treatment comparisons in meta-analysis of randomized controlled trials.

When little or no data directly comparing two treatments are available, investigators often rely on indirect comparisons from studies testing the treatments against a control or placebo. One approach to indirect comparison is to pool findings from the active treatment arms of the original controlled trials. This approach offers no advantage over a comparison of observational study data and is prone to bias. We present an alternative model that evaluates the differences between treatment and placebo in two sets of clinical trials, and preserves the randomization of the originally assigned patient groups. We apply the method to data on sulphamethoxazole-trimethoprim or dapsone/pyrimethamine as prophylaxis against Pneumocystis carinii in HIV infected patients. The indirect comparison showed substantial increased benefit from the former (odds ratio 0.37, 95% CI 0.21 to 0.65), while direct comparisons from randomized trials suggests a much smaller difference (risk ratio 0.64, 95% CI 0.45 to 0.90; p-value for difference of effect = 0.11). Direct comparisons of treatments should be sought. When direct comparisons are unavailable, indirect comparison meta-analysis should evaluate the magnitude of treatment effects across studies, recognizing the limited strength of inference.

AIDS-Related Opportunistic Infections↗

PubMed2002

Using comparison charts to assess performance measurement data.

BACKGROUND: In 1997 the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) announced the ORYX initiative, which integrates outcomes and other performance measurement data into the accreditation process. JCAHO uses control and comparison charts to identify performance trends and patterns that are provided to JCAHO surveyors in advance of a health care organization's (HCO's) survey. During the survey, the HCO is asked to explain its rationale for its selection of performance measures, how the ORYX data have been analyzed and used to improve performance, and the outcomes of these activities. CONSTRUCTING COMPARISON CHARTS: A comparison chart, a graphical summary of the comparison analysis, consists of actual (or observed) rates, expected rates, and expected ranges (upper and lower limits) for a given time frame. The expected range describes the degree of certainty that a given point is different from the average score (population). THE USE OF COMPARISON CHARTS: Comparison charts are primarily useful for telling an HCO whether one of its selected performance measures may be evidencing one of the three types of measurement outcomes: exemplary performance, average performance, or substandard performance (indicating an opportunity for improvement). The comparison charts compare an HCO's outcomes to those of its comparison group or to its risk-adjusted data. The charts provide guidance to an HCO about whether it should continue to monitor a process so as to maintain its current level of performance or whether it should try to improve its current performance.

Accreditation↗

PubMed1990

The affective consequences of social comparison: either direction has its ups and downs.

Research on social comparison processes has assumed that a comparison in a given direction (upward or downward) will lead to a particular affective reaction. In contrast, the present two studies proposed and found that a comparison can produce either positive or negative feelings about oneself, independent of its direction. Several factors moderated the tendency to derive positive or negative affect from upward and downward comparisons. In Study 1, cancer patients low in self-esteem and with low perceived control over their symptoms and illness were more likely to see downward comparisons as having negative implications for themselves. Those low in self-esteem were also more likely to perceive upward comparisons as negative. In Study 2, individuals with high marital dissatisfaction and those who felt uncertain about their marital relationship were more likely to experience negative affect from upward and downward comparisons. The implications of these findings for social comparison theory and for the coping and adaptation literature are discussed.

Adaptation, Psychological↗

PubMed2000

Depressive personality styles, dysphoria, and social comparisons in everyday life.

"Sociotropic" people are supposedly vulnerable to dysphoria after negative interpersonal events, whereas "autonomous" people are supposedly vulnerable to achievement-related failures. The present study examined whether these personality styles are borne out in social comparison processes. For 3 weeks, 27 sociotropic and 35 autonomous undergraduates completed records of their social comparisons. Depressive personality style moderated comparison frequency and the affective consequences of comparisons, especially for dysphoric individuals: Dysphoric respondents were especially likely to make comparisons in domains that were congruent with their personalities, and comparisons in congruent domains were associated with greater mood change than comparisons in other domains, perhaps especially for dysphoric respondents. These results have implications for the literatures on social comparison and on depressive personality styles.

Adaptation, Psychological↗