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191.
B Lowenkron 《Journal of the experimental analysis of behavior》1989,52(3):293-309
Three experiments examined the performance of 4-year-old children in matching geometric stimuli. Performance was developed as a simulation in which all components of the behavior were overt and directly measured. A correct match depended on the state of an instructional stimulus: the background color of the display. In the first two experiments, on nonidentity trials (signified by a green background) the next longer length, larger size, or greater distance was correct. With a blue background, a comparison identical to the sample was correct. In Experiment 3, red was added for which shorter, smaller, or nearer was correct. Also here, on nonidentity trials, if a comparison of the correct length was not presented, the children adjusted their search target to the comparison of the next succeeding size (larger or smaller) so as to maintain a constant matching relation. Subsequently, when exposure to the instructional stimulus was reduced to presentation only at the beginning of each trial, performance simulated matching based on instructions about abstract relations. In all experiments, accurate matching generalized across novel stimuli and reduced exposure to the instructional stimuli. 相似文献
192.
Henry E. Brady 《Psychometrika》1989,54(2):181-202
Interpersonally incomparable responses pose a significant problem for survey researchers. If the manifest responses of individuals differ from their underlying true responses by monotonic transformations which vary from person to person, then the covariances of the manifest responses tools such as factor analysis may yield incorrect results. Satisfactory results for interpersonally incomparable ordinal responses can be obtained by assuming that rankings are based upon a set of multivariate normal latent variables which satisfy the factor or ideal point models of choice. Two statistical methods based upon these assumptions are described; their statistical properties are explored; and their computational feasibility is demonstrated in some simulations. We conclude that is possible to develop methods for factor and ideal point analysis of interpersonally incomparable ordinal data.This research was begun in the supportive enviroment of the Survey Research Center at the University of California, Berkeley. Financial support was provided by Percy Tannenbaum, Director of the Center, by Allan Sindler, Dean of the Graduate School of Public Policy at Berkeley, by the Data Center of Harvard University, and by the National Science Foundation through grant number SES-84-03056. Chris Achen, Doug Rivers, and members of the Harvard-MIT econometrics seminar provided useful comments. 相似文献
193.
B Lowenkron 《Journal of the experimental analysis of behavior》1988,50(2):163-172
In an extension of prior research, four retarded children were trained under an identity matching-to-sample procedure containing features previously shown to produce controlled generalization to novel stimuli. They first were taught to relate a particular handsign to the sample shape, then to maintain the handsign over a delay interval, and then to select from an array the comparison shape that permitted the handsign to be maintained (i.e., the shape identical to the sample). An initial test revealed little generalization of matching to novel stimuli, but after handsigns were trained to these stimuli, accurate generalized matching appeared immediately. The results replicated prior findings and demonstrated particular features of stimulus control sufficient to enable generalized matching. A behavioral account of relational matching was supported. The technique used in this study was shown to be effective in teaching abstract relations to nonverbal retarded children. 相似文献
194.
Oral self-administration of pentobarbital by rhesus monkeys: relative reinforcing effects under concurrent fixed-ratio schedules. 总被引:3,自引:2,他引:1 下载免费PDF全文
During daily 3-hr sessions, orally delivered pentobarbital solutions and water, or two separate pentobarbital solutions, were concurrently available to rhesus monkeys according to fixed-ratio schedules of mouth contacts with a spout. First water, and then each of four "comparison-concentration" pentobarbital solutions (0.0625, 0.25, 1, and 4 mg/mL), was successively available from one spout for a block of sessions under a fixed-ratio-64 (three monkeys) or fixed-ratio-16 (one monkey) schedule. Under an identically sized fixed-ratio schedule, deliveries of a "standard-concentration" pentobarbital solution were concurrently available from a second spout. The concentration of the standard solution remained unchanged throughout testing of the series of comparison solutions. Each of three pentobarbital concentrations (4, 1, and 0.25 mg/mL) in turn served as the standard concentration. Within each pair of concurrently available solutions, the higher drug concentration maintained more behavior than the lower concentration. Thus when monkeys were provided with concurrent access to different pentobarbital concentrations, relative reinforcing effects were directly related to drug concentration. Further, the amount of behavior maintained by a particular drug concentration was dependent on the concentration of the concurrently available drug solution. Thus, the relative effectiveness of a reinforcer in maintaining behavior is a function of both the reinforcer's magnitude and the availability of alternative reinforcers in the environment. 相似文献
195.
Equivalence of marginal likelihood of the two-parameter normal ogive model in item response theory (IRT) and factor analysis of dichotomized variables (FA) was formally proved. The basic result on the dichotomous variables was extended to multicategory cases, both ordered and unordered categorical data. Pair comparison data arising from multiple-judgment sampling were discussed as a special case of the unordered categorical data. A taxonomy of data for the IRT and FA models was also attempted.The work reported in this paper has been supported by Grant A6394 to the first author from the Natural Sciences and Engineering Research Council of Canada. 相似文献
196.
A rasch model for continuous ratings 总被引:1,自引:0,他引:1
Hans Müller 《Psychometrika》1987,52(2):165-181
A unidimensional latent trait model for continuous ratings is developed. This model is an extension of Andrich's rating formulation which assumes that the response process at latent thresholds is governed by the dichotomous Rasch model. Item characteristic functions and information functions are used to illustrate that the model takes ceiling and floor effects into account. Both the dichotomous Rasch model and a linear model with normally distributed error can be derived as limiting cases. The separability of the structural and incidental parameters is demonstrated and a procedure for estimating the parameters is outlined. 相似文献
197.
Thomas G. Plante Amy Lantis Giancarlo Checa 《International journal of stress management》1997,4(2):89-99
The study sought to evaluate the influence of gender, hypertension risk, and aerobic fitness on cardiovascular responses to
laboratory-induced stress. Sixty nonsymptomatic subjects (30 males, 30 females) participated in the experiment. Half of the
subjects had at least one biological parent with hypertension, while half had no parental history of hypertension and served
as comparison subjects. Subjects completed a laboratory procedure measuring cardiovascular responses (i.e., pulse rate and
blood pressure) while performing stressful laboratory tasks (i.e., the Stroop Color Naming Test and a sham IQ test). Aerobic
fitness (i.e., VO2max using the Bruce protocol) was also determined using a submaximal treadmill test in the laboratory. Results suggest that males
with a family history of hypertension were more stress responsive based on systolic blood pressure, while females were more
stress-responsive according to pulse rate activity. Fitness levels were significantly associated with diastolic blood pressure
throughout the stress and recovery periods but were unrelated to pulse rate and systolic blood pressure. 相似文献
198.
Enhancement of conditioned autonomic responses in monkey when preshock signals occasion operant suppression. 下载免费PDF全文
D D Kelly 《Journal of the experimental analysis of behavior》1980,33(2):275-284
Classical pairings of a sound stilulus with shock elicited larger magnitude and more rapidly conditioned autonomic responses when subjects were responding on variable-interval schedules for food than when they were eating freely available food. The difference was not attributable to changes in control values of heart rate and blood pressure, or to alterations in motor activity, but appeared related to operant suppression. 相似文献
199.
Effects of barbiturates and other sedative hypnotics in pigeons trained to discriminate phencyclidine from saline. 总被引:3,自引:3,他引:0 下载免费PDF全文
Pigeons were trained to peck the center key (lighted white) of three response keys to turn off the center keylight and to light one of the side keys with a red keylight and the other side key with a green keylight. Five responses (fixed-ratio component) on either side key relighted the center key. Food was delivered following 10 fixed-ratio components on the red key if 1.5 mg/kg phencyclidine had been given before the session. The position of the red and green keylights on the side keys varied randomly each time they were lighted by a peck on the center key. Subsequently, increasing doses of phencyclidine, barbital, amobarbital, phenobarbital, methaqualone, methyprylon, diazepam, oxazepam, and d-amphetamine were substituted for the training dose of phencyclidine, using a cumulative dosing procedure. At low doses of the sedative hypnotics, birds pecked the keylight color associated with saline. At higher doses, birds pecked both key colors. At the highest doses of pentobarbital and amobarbital, some birds responded almost exclusively On he color associated with phencyclidine. When responding on keys of both colors occurred following administration of phencyclidine or other sedative hypnotics, this responding was controlled by key position rather than by key color. 相似文献
200.