Some models for individual-group comparisons and group behavior

In problem solving situations, it has been suggested the superiority of groups over individuals is due simply to the fact that groups consist of several individuals. In this paper, the Lorge and Solomon [1955] approach to such situations is reexamined using the method of maximum likelihood. Extensions to trichotomous response situations are also presented, and the resulting models are applied to data gathered by Staub [1970]. The partitioning of the likelihood ratio goodness-of-fit statistic is then discussed in order that the effects of additional variables on the response variate can be assessed. Finally, the small sample behavior of the likelihood ratio statistic is examined.This research was supported in part by Research Contract No. NSF GS-2818 from the Division of Social Sciences of the National Science Foundation to the Department of Statistics, The University of Chicago.Now at the University of Minnesota.     

Gender comparisons of college students' attitudes toward sexual behavior

Questionnaires were distributed to 641 undergraduates at a large southeastern university to elicit opinions concerning various forms of premarital sexual behavior. Hypotheses were developed to determine whether there were differences between the attitudes of males and females. Significant differences were found between males' and females' attitudes toward premarital sex when the couple is casually acquainted, and attitudes toward extramarital sex, oral-genital sex, and anal sex. However, significant differences were not found between males' and females' attitudes toward premarital sex when the couple is in love, attitudes toward premarital sex when the couple is engaged, and attitudes toward masturbation, homosexuality, and sexual fantasizing. Males' attitudes toward various forms of sexual behavior were more liberal than those of females.     

A scaled difference chi-square test statistic for moment structure analysis

A family of scaling corrections aimed to improve the chi-square approximation of goodness-of-fit test statistics in small samples, large models, and nonnormal data was proposed in Satorra and Bentler (1994). For structural equations models, Satorra-Bentler's (SB) scaling corrections are available in standard computer software. Often, however, the interest is not on the overall fit of a model, but on a test of the restrictions that a null model sayM ₀ implies on a less restricted oneM ₁. IfT ₀ andT ₁ denote the goodness-of-fit test statistics associated toM ₀ andM ₁, respectively, then typically the differenceT _d =T ₀−T ₁ is used as a chi-square test statistic with degrees of freedom equal to the difference on the number of independent parameters estimated under the modelsM ₀ andM ₁. As in the case of the goodness-of-fit test, it is of interest to scale the statisticT _d in order to improve its chi-square approximation in realistic, that is, nonasymptotic and nonormal, applications. In a recent paper, Satorra (2000) shows that the difference between two SB scaled test statistics for overall model fit does not yield the correct SB scaled difference test statistic. Satorra developed an expression that permits scaling the difference test statistic, but his formula has some practical limitations, since it requires heavy computations that are not available in standard computer software. The purpose of the present paper is to provide an easy way to compute the scaled difference chi-square statistic from the scaled goodness-of-fit test statistics of modelsM ₀ andM ₁. A Monte Carlo study is provided to illustrate the performance of the competing statistics. This research was supported by the Spanish grants PB96-0300 and BEC2000-0983, and USPHS grants DA00017 and DA01070.     

Childhood and adult behavior disorder: Some experimental comparisons

Seventy-six children with diagnoses of behavior disorder were tested with a motor conditional reflex test and a word association test. Essentially no differences were found when test performance was compared with that of 142 normal controls. When the diagnoses were divided into neuroses, adjustment reaction of childhood, and personality disorder, none of these subgroups showed any distinctive difference. Experimental differences between clinically excitatory and inhibitory types could not be established. The Russian reports about abnormal basic Pavlovian parameters could not be confirmed. In adult behavior disorder marked disturbances of functions are found. It is suggested that the worse prognosis in adult neurotic conditions is related to such pathophysiological factors as passive inhibition, weakness of active inhibition, inertness and complex structures with pathological excitation and inertia.     

Upward and downward social comparisons can decrease prosocial behavior

This experiment addressed whether upward or downward social comparisons can affect people's prosocial behavior toward the comparison targets. Undergraduates (N = 123) completed an inkblot test and then were randomly assigned to conditions in which they were told that their performance was either inferior or superior to their peers. A control group was given no performance feedback. Participants' self‐reported prosocial behaviors were measured 2 days later. Results indicated that both the upward and downward comparison groups engaged in significantly less prosocial behavior than did the control group and that empathy toward their peers mediated this effect. Our findings suggest that upward or downward comparison can make people feel less empathic toward the targets and thus less inclined to help them.     

Context and the inverse base rate effect

Recent categorization research set in abstract medical diagnosis contexts has demonstrated an ‘inverse base rate effect’, whereby subjects make diagnoses which are consistent with base rates when presented with some sets of symptoms, but inconsistent with base rates when presented with other sets of symptoms. This paper reports three experiments which demonstrate that whether or not the inverse base rate effect is observed depends on the context in which categorization takes place. Inverse base rate effects are replicated in the abstract medical diagnosis context used in prior research, but not in a relatively realistic financial auditing setting, a less realistic financial auditing setting, or a very abstract generic setting. These results indicate that the inverse base rate effect may not generalize to applied settings, suggesting that interventions designed to mitigate the inverse base rate effect should not be instituted without first determining the existence of the effect in the particular setting in question.     

A stochastic model for paired comparisons of social stimuli

A stochastic model for paired comparisons of multiattribute social stimuli is proposed where one objective is to find the relative importance of the attributes for a judge. The model can be conceived as a special strict binary utility model, i.e., a BTL-model, and is related to of the stimuli are linear combinations of functions of the attributes of the stimuli. The model neither assumes that the functions are fixed in advance nor that different judges have the same set of functions. The choice among such functions, however, is admitted only within a finite scope. Within the framework of exponential families, maximum likelihood estimators and tests are derived and applied to data coming from two psychological experiments.     

Internet-based instruction of the principles of base rate and prediction: A demonstration project

An Internet-based instructional module was developed using Netscape 2.0 as the graphical interface. The content concerned Bayesian probabilities and expected outcomes associated with the use of urine drug screens. JavaScript enabled interactive calculations of outcome probabilities given a selected set of parameters, and AppleScript and Claris Filemaker Pro monitored and recorded student activity and progress. The module was initially used in an undergraduate class on alcohol and drugs and subsequently evaluated on a sample of undergraduates. Student response was favorable, and student learning assessed by performance on an exam was good. Students who described themselves as not computer literate did not particularly enjoy the experience, although they performed as well as others on the test. The success of this demonstration project has led to more ambitious implementations, particularly those that monitor student activities and provide intelligent feedback.     

Likelihood ratios: A simple and flexible statistic for empirical psychologists

Empirical studies in psychology typically employ null hypothesis significance testing to draw statistical inferences. We propose that likelihood ratios are a more straightforward alternative to this approach. Likelihood ratios provide a measure of the fit of two competing models; the statistic represents a direct comparison of the relative likelihood of the data, given the best fit of the two models. Likelihood ratios offer an intuitive, easily interpretable statistic that allows the researcher great flexibility in framing empirical arguments. In support of this position, we report the results of a survey of empirical articles in psychology, in which the common uses of statistics by empirical psychologists is examined. From the results of this survey, we show that likelihood ratios are able to serve all the important statistical needs of researchers in empirical psychology in a format that is more straightforward and easier to interpret than traditional inferential statistics.     

A generalized signal detection model to predict rational variation in base rate use

The predominant models of rational behavior currently used to analyze a large class of experiments imply that subjects neglect or place insufficient weight on base rates when making probabilistic judgments. We argue that the evidence is inadequate for this conclusion because the models make needlessly restrictive assumptions about how base rates should be used. The restrictive assumptions stem from a misuse of Bayes' rule that ignores specific aspects of how the proportions arose. We develop a model of rational behavior that generalizes signal detection theory to reflect the environment subjects routinely face and we reexamine the relevant experimental literature. Variation observed in subjects' responses to base rate information is explained by the present rational model more fully than by extant models.     

A challenge for Super-Humeanism: the problem of immanent comparisons

Synthese - According to the doctrine of Super-Humeanism (Esfeld in Synthese. https://doi.org/10.1007/s11229-017-1426-8 , 2017), the world’s mosaic consists only of permanent matter points and...     

A note on the use of triads for paired comparisons

When scaling a large number of stimuli from comparative judgments, considerable savings in time and labor may be realized if stimuli are presented in triad form rather than in pairs. If, forN stimuli, the proper configuration of triads can be assembled so that all possible pairs appear once, the paired judgment matrix may be reproduced with one-third fewer judgments and two-thirds fewer presentations than would be required with complete pairing. A simple procedure is described for enumerating triad configurations for whichN is an odd multiple of three.     

The adjusted rand statistic: A SAS macro

A macro for calculating the Hubert and Arabie (1985) adjusted Rand statistic is presented. The adjusted Rand statistic gives a measure of classification agreement between two partitions of the same set of objects. The macro is written in the SAS macro language and makes extensive use of SAS/IML software (SAS Institute, 1985a, 1985b). The macro uses two different methods of handling missing values. The default method assumes that each object that has a missing value for the classification category is in its own separate category or cluster for that classification. The optional method places all objects with a missing value for the classification category into the same category for that classification.This study was supported in part by Individual National Research Service Award F32 DA 05283 from the National Institute on Drug Abuse.Requests for the Macro code can be sent via BITNET: CUSGPXH @ UCLAMVS. A copy of the macrocode can also be obtained by sending a stamped self-addressed mailer and a PC-DOS formatted floppy diskette to Paul Hoffman, 5628 MSA, UCLA, Los Angeles, CA 90024-1557.     

A base logic for default reasoning

Based on a close study of benchmark examples in default reasoning, such as Nixon Diamond, Penguin Principle, etc., this paper provides an in depth analysis of the basic features of default reasoning. We formalize default inferences based on Modus Ponens for Default Implication, and mark the distinction between “local inferences” (to infer a conclusion from a subset of given premises) and “global inferences” (to infer a conclusion from the entire set of given premises). These conceptual analyses are captured by a formal semantics that is built upon the set-selection function technique. A minimal logic system M of default reasoning that accommodates Modus Ponens for Default Implication and suitable for local inferences is proposed, and its soundness is proved. __________ Translated from Zhexue Yanjiu 哲学研究 (Philosophical Studies), 2003 (special issue) by Ye Feng     

Automatic optimism: Biased use of base rate information for positive and negative events

People generally judge that positive events will occur in their lives and negative events will not, even when both events have the same objective likelihood to occur. In four studies, we examined the possibility that this optimistic bias is the result of people’s automatic affective reactions to future events. Studies 1 and 2 demonstrate, in two different contexts, that people are consistently optimistic in their predictions, despite identical base rates for positive and negative events. In Study 2, optimistic bias was not influenced by incentives for motivated reasoning or rewards for accuracy, suggesting that bias was the result of automatic processes. Studies 3 and 4 showed that optimistic bias was more pronounced when predictions were speeded and when participants made predictions after exposure to affectively valenced words. Together, these findings suggest that people optimistically interpret base rates and that this optimism is due to an effortless affective process.     

The no miracles argument without the base rate fallacy

According to an argument by Colin Howson, the no-miracles argument (NMA) is contingent on committing the base-rate fallacy and is therefore bound to fail. We demonstrate that Howson’s argument only applies to one of two versions of the NMA. The other version, which resembles the form in which the argument was initially presented by Putnam and Boyd, remains unaffected by his line of reasoning. We provide a formal reconstruction of that version of the NMA and show that it is valid. Finally, we demonstrate that the use of subjective priors is consistent with the realist implication of the NMA and show that a core worry with respect to the suggested form of the NMA can be dispelled.     

An inverse base rate effect with continuously valued stimuli

It is well known that people do not always make normative use of information about relative frequencies of categories when making categorical judgments. The "inverse base rate" effect (Medin & Edelson, 1988) is a typical example of this: Subjects violate normative reasoning principles by assigning certain ambiguous stimuli as belonging to the less frequent of two categories, rather than to the more common category. This effect has been explained as being due to the shifting of attention from shared stimulus features to distinctive features during learning. When stimuli are defined by values along continuous dimensions, rather than by the presence and absence of features, then attention could shift between dimensions or between values, or both. In three experiments, base rate differences were used to determine the way in which attention is shifted during learning about stimuli with continuously valued dimensions. Simulation modeling shows that the results are consistent with the movement of attention both between and within stimulus dimensions.