Personality, stress and disease: description and validation of a new inventory

The construction of a new Personality-Stress Inventory is discussed, based on previous research and other types of inventory constructed on the same principles. Scores on the inventory divide people into six types, selectively prone to different types of disease. The instrument is administered twice, with six months intervening, and changes in the inventory scores are prognostic of the probability of contracting different diseases. Evidence is presented to show the validity of the questionnaire and the method used.     

Analyzing sequential categorical data: Individual variation in markov chains

Markov chains are probabilistic models for sequences of categorical events, with applications throughout scientific psychology. This paper provides a method for anlayzing data consisting of event sequences and covariate observations. It is assumed that each sequence is a Markov process characterized by a distinct transition probability matrix. The objective is to use the covariate data to explain differences between individuals in the transition probability matrices characterizing their sequential data. The elements of the transition probability matrices are written as functions of a vector of latent variables, with variation in the latent variables explained through a multivariate regression on the covariates. The regression is estimated using the EM algorithm, and requires the numerical calculation of a multivariate integral. An example using simulated cognitive developmental data is presented, which shows that the estimation of individual variation in the parameters of a probability model may have substantial theoretical importance, even when individual differences are not the focus of the investigator's concerns.Research contributing to this article was supported by B.R.S. Subgrant 5-35345 from the University of Virginia. I thank the DADA Group, Bill Fabricius, Don Hartmann, William Griffin, Jack McArdle, Ivo Molenaar, Ronald Schoenberg, Simon Tavaré, and several anonymous reviewers for their discussion of these points.     

Continuous and discrete latent structure models for item response data

Relations are examined between latent trait and latent class models for item response data. Conditions are given for the two-latent class and two-parameter normal ogive models to agree, and relations between their item parameters are presented. Generalizationss are then made to continuous models with more than one latent trait and discrete models with more than two latent classes, and methods are presented for relating latent class models to factor models for dichotomized variables. Results are illustrated using data from the Law School Admission Test, previously analyzed by several authors.     

Finding relations between systems of entities: a multivariate approach

A procedure to find out the relationship between systems of entities is described. The crux of the approach depends on projecting the systems to be compared on the same arbitrary hyperspace so that any two systems of entities can be related. The procedure described applies to data presented in square or rectangular non-singular matrices and provides a procedure to determine multiple regression coefficients, multiple correlations, canonical correlations and the relationships between the inner product of the row vectors and of the column vectors of the matrices involved. The operations described apply to raw values, deviation or standard scores, and may help in interdisciplinary research, though the risks involved in the blind application of a mathematical abstract formulation should not be ignored.     

The role of compliance in hypnotic and nonhypnotic analgesia

We modified the standard procedure for administering finger pressure pain in order to assess the extent to which subjects biased their reports of pain reduction when exposed to compliance-inducing instructions. Experiment 1 used only highly hypnotizable subjects and found that compliance-induced reductions in reported pain were about half as large as the reported reductions produced by hypnotic analgesia suggestions. Experiment 2 used low as well as high hypnotizables and administered hypnotic or nonhypnotic analgesia instructions and compliance instructions to the same subjects on separate pain trials. Reported pain reductions produced by hypnotic and nonhypnotic analgesia suggestions and those produced by compliance instructions were substantially and significantly correlated. Furthermore, hypnotizability correlated with compliance-induced reported pain reductions as highly as it correlated with the reported reductions produced by hypnotic analgesia suggestions. Among high hypnotizables (but not low hypnotizables) compliant responding was predicted by social desirability. The findings of both studies indicate that compliance strongly influences the reports of hypnotic and nonhypnotic analgesia proffered by high hypnotizables. The role of compliance in the pain reductions reported by low hypnotizables is less clear-cut.     

Syntactic comprehension in Japanese aphasics: effects of category and thematic role order.

Syntactic comprehension disturbances in Japanese aphasics were investigated focusing on the role of category order and thematic role order. The data from Japanese aphasics show that the canonicity of thematic role order determines the ease of interpretation of different sentence types. This finding implies that language-specific factors, rather than language-universal factors, influence the sentence comprehension mechanisms that are retained by aphasic patients.     

The predictive validity of teacher nominations: A five-year followup of at-risk youth

The purpose of this study was to examine the predictive validity of a teacher nomination procedure for identifying at- risk children. Two hundred and twenty-five children were nominated by their teachers as well- adjusted (n= 75), socially withdrawn (n=76), or socially aggressive (n=74) during the fourth grade. Five years later, 198 of these children (88%) were located and their adjustment evaluated. Significant differences among the nominated children were found on a variety of measures, including academic grades, sociometric status, and social behavior. In addition, differences in school dropout and delinquent offenses were noted. Results are discussed in terms of the validity of teacher nomination procedures and their utility in identifying at- risk youth.     

Rate variables and automatized naming in developmental dyslexia

The rate variable in rapid automatized naming (RAN) was investigated in 50 adolescent and 40 adult students with developmental dyslexia, in matched normal controls, and in learning-disabled students without reading difficulties. Visual stimuli depicting familiar colors and common objects were presented in isolation at three film speeds and three exposure times. Film speed and exposure time contributed as independent variables to error rate; and dyslexic subjects of both age groups made significantly more naming errors than controls. Dyslexic subjects also responded with longer naming latencies than controls when the same RAN stimuli were presented in a continuous sequential mode as a matrix of rows and columns. Naming latencies in the sequential presentation were highly correlated with naming errors in the film version. The implications of reduced naming rates for nongraphological stimuli in developmental dyslexia are discussed.     

Stimulus repetition effects and the dimension-feature distinction in alternative targets

The negative repetition effect (NRE) refers to a poorer perception of the target in noise-same-as-target than in noise-alternative-target displays. Using the parenthesis as target and noise that are either identical or different in orientation, we tested predictions derived from a feature-specific inhibition model (Bjork & Murray, 1977) that explains the NRE as arising from inhibitory interactions among channels handling identical inputs. Contrary to our expectation of evidence for orientation-specific inhibition, a positive repetition effect (PRE) was observed. We also found a PRE for the dimension target sets whose stimuli differ only in orientation and an NRE for the feature target sets whose stimuli differ in the number of elements. Further experiments that systematically varied relationships between alternative targets indicate that these basic findings, termed the stimulus attributes effects, do not arise from pattern masking, perceptual strategies, or response bias.     

The effects of right hemisphere damage on the pragmatic interpretation of conversational remarks

The ability to interpret conversational utterances was assessed in a group of 12 male patients with unilateral right hemisphere brain damage (RHD) and 12 non-brain-damaged, age-matched male control subjects. Subjects listened to short vignettes which described both the affective tone of the relationship between a speaker and an actor, and the actor's performance on a task. Each vignette concluded with the speaker characterizing the actor's performance. In half of the items, the speaker's utterance was literally true; in the other half, the utterance was literally false and invited a nonliteral interpretation. Results showed no appreciable differences in the performance of control subjects and RHD patients when interpreting literally true utterances. In contrast, the two groups differed reliably when interpreting the pragmatic intent of nonliteral utterances: Control subjects used information about both the actor's performance and the speaker-actor relationship, while RHD patients demonstrated difficulty in using the information about the speaker-actor relationship. Results have implications for patients' understanding of essential elements of conversations, such as characters' internal states and their intentions in employing different forms of literal and nonliteral language.