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1.
A computer program, which produces restricted randomizations of numbers as an aid in counterbalancing large experimental designs, is described. The input to the program is a series of specifications for sampling a pool of random numbers. For example, it might be specified that each number in the pool be selected at least once and not more than twice in each replication of the experiment. The output would be a restricted randomization meeting these specifications. The program has been used in several memory experiments and could be used in other experimental paradigms in learning and perception.  相似文献   

2.
Various theorems are obtained forN-trial sample sequences from the general two-state, first-order Markov chain with stationary transition probabilities. Four lemmas which facilitate the derivations are given. A brief discussion of applications to binary data, estimation, and evaluation is given, including a maximum-likelihood procedure for estimating transition probabilities which are restricted by inequalities.  相似文献   

3.
A multiple-response baseline of four activities was established using gerbils as subjects. When one of the baseline responses was punished (Experiment 1) or restricted (Experiments 2 and 3), only the most probable of the alternative baseline responses increased. The response most likely to follow the punished or restricted responses during baseline sessions was also suppressed during subsequent punishment or response-restriction treatment.  相似文献   

4.
Luce and Marley [2005. Ranked additive utility representations of gambles: Old and new axiomatizations. Journal of Risk and Uncertainty, 30, 21-62] examined various relations between mathematical forms for the utility of joint receipt ⊕ of gambles and for the utility of uncertain gambles. Their assumptions lead to a bisymmetry functional equation which, when the gambles are ranked, is defined on a restricted domain. Maksa [1999. Solution of generalized bisymmetry type equations without surjectivity. Aequationes Mathematicae, 57, 50-74] solved the general case and Kocsis [2007. A bisymmetry equation on restricted domain. Aequationes Mathematicae, 73, 280-284] presents the solution for the ranked case. The latter solution allows us to solve open problem 5 in Luce and Marley (2005) by showing that the assumptions of their Theorem 19 for an order-preserving ranked additive utility (RAU) representation U imply that U is a ranked weighted utility (RWU) representation that is additive over ⊕.  相似文献   

5.
In this article, a Windows program for analyzing measurement invariance in two different populations is described. Factor analysis is a common way of assessing measurement invariance, and restricted factor analysis is now the most popular method. However, applied researchers have usually found that the theoretical advantages of restricted factor analysis do not always apply in practical situations. For example, when the participant sample is large, as is the case in Internet-based questionnaires, the available software for restricted factor analysis might fail to converge on a solution. Our program is based on unrestricted factor analysis and considers the three parameters that define factor invariance: difficulties, discriminations, and residual variances. The statistical significance of the tests for evaluating invariance is obtained using Bootstrap resampling procedures. A real-life example demonstrates the usefulness of the program.  相似文献   

6.
Wandering is a difficult-to-manage behavior problem for individuals with cognitive impairments that can jeopardize safety if an individual enters a hazardous area or becomes lost. This study investigated the effects of a cloth barrier on entry into an unsafe area. The cloth barrier reduced entry into the restricted area and had high treatment acceptability.  相似文献   

7.
This exploratory study examined the frequency and nature of providers' contact with families of persons with severe mental illness. Fifty-nine providers in six community mental health programs completed a self-administered survey. A subsample of 8 providers also completed two in-depth interviews. Although most providers had some family contact, the contact was restricted to a small percent of their caseloads. The nature of contact that providers have with families is generally limited by their professional role. Best practice guidelines for the treatment of mental illness and agency administrators responsible for instituting these guidelines will need to clarify the types of providers who are expected to implement various aspects of family involvement.  相似文献   

8.
Two experiments are reported in which student subjects attempted to discover a principle obtaining among pairs of numbers and letters. In the first experiment, subjects were more successful when they were free to select whatever number-letter pairs they wished than if they were restricted in whole or in part to pairs specified by the experimenter. In the second experiment, subjects who did discover the principle were compared to those who did not. Successful subjects were shown to be slightly more systematic in their approach to the task, to work at a faster pace, to write down more positive instances, and to have a much stronger tendency to vary only one variable of the task at a time.

Wason (1960) reported a study in which subjects tried to discover a principle applying to instances each of which consisted of three numbers. He discovered that subjects mostly showed enumerative rather than eliminative induction, i.e. they made little use of instances that would have enabled them to eliminate wrong hypotheses. Wetherick (1962) found that by modifying Wason's procedure in certain ways, enumerative behaviour was reduced and the subject's chance of discovering the principle was increased. Elimination of hypotheses remained infrequent.

In the Wason study, the subject was free to write down, for each instance, any three numbers he wished, i.e. his choice of instances was not restricted in any way. This may account in part for the behaviour Wason observed. In the first experiment to be reported here, the subject is restricted, in various degrees, in his choice of instances, to determine whether the principle is discovered more (or less) readily under such restriction.  相似文献   

9.
Stefan Schubert 《Synthese》2012,187(2):305-319
A measure of coherence is said to be reliability conducive if and only if a higher degree of coherence (as measured) results in a higher likelihood that the witnesses are reliable. Recently, it has been proved that several coherence measures proposed in the literature are reliability conducive in a restricted scenario (Olsson and Schubert 2007, Synthese 157:297?C308). My aim is to investigate which coherence measures turn out to be reliability conducive in the more general scenario where it is any finite number of witnesses that give equivalent reports. It is shown that only the so-called Shogenji measure is reliability conducive in this scenario. I take that to be an argument for the Shogenji measure being a fruitful explication of coherence.  相似文献   

10.
A translation technique is presented which transforms a class of First Order Logic formulas, called Restricted formulas, into ground formulas. For the formulas in this class the range of quantified variables is restricted by Domain formulas.If we have a complete knowledge of the predicates involved in the Domain formulas their extensions can be evaluated with the Relational Algebra and these extensions are used to transform universal (respectively existential) quantifiers into finite conjunctions (respectively disjunctions).It is assumed that the complete knowledge is represented by Completion Axioms and Unique Name Axioms à la Reiter. These axioms involve the equality predicate. However, the translation allows to remove the equality in the ground formulas and for a large class of formulas their consequences are the same as the initial First Order formulas. This result open the door for the design of efficient deduction techniques.  相似文献   

11.
Organizational and validation researchers often work with data that has been subjected to selection on the predictor and attrition on the criterion. These researchers often use the data observed under these conditions to estimate either the predictor or criterion's restricted population means. We show that the restricted means due to direct or indirect selection are a function of the population means plus the selection ratios. Thus, any difference between selected mean groups reflects the population difference plus the selection ratio difference. When there is also attrition on the criterion, the estimation of group differences becomes even more complicated. The effect of selection and attrition induces measurement bias when estimating the restricted population mean of either the predictor or criterion. A sample mean observed under selection and attrition does not estimate either the population mean or the restricted population mean. We propose several procedures under normality that yield unbiased estimates of the mean. The procedures focus on correcting the effects of selection and attrition. Each procedure was evaluated with a Monte Carlo simulation to ascertain its strengths and weaknesses. Given appropriate sample size and conditions, we show that these procedures yield unbiased estimators of the restricted and unrestricted population means for both predictor and criterion. We also show how our findings have implications for replicating selected group differences.  相似文献   

12.
A field experiment investigated violation of the spacing norm which keeps distance between people in a particular type of crowding, high social density, when the number of people in an area is large but space is not necessarily restricted. The proportion of people passing a drinking fountain who drank from the fountain was observed in conditions of high and low social density and, for each of these densities, when a confederate stood one foot from the fountain and when no one stood near the fountain. Three hundred passersby were observed in each of the four conditions. The observations supported the conclusion that the spacing norm was followed in low social density ( p <.01) but violated under conditions of high social density for reasons other than lack of space. Interpretation focused on several concomitants of high social density, especially excessive social stimulation, and the accompanying tendencies to attribute less of the usual social meanings to people and honor fewer of their expectations.  相似文献   

13.
In this paper we present BTC, which is a complete logic for branchingtime whose modal operator quantifies over histories and whose temporal operators involve a restricted quantification over histories in a given possible choice. This is a technical novelty, since the operators of the usual logics for branching-time such as CTL express an unrestricted quantification over histories and moments. The value of the apparatus we introduce is connected to those logics of agency that are interpreted on branching-time, as for instance Stit Logics.  相似文献   

14.
A novel modular connectionist architecture is presented in which the networks composing the architecture compete to learn the training patterns. An outcome of the competition is that different networks learn different training patterns and, thus, learn to compute different functions. The architecture performs task decomposition in the sense that it learns to partition a task into two or more functionally independent tasks and allocates distinct networks to learn each task. In addition, the architecture tends to allocate to each task the network whose topology is most appropriate to that task. The architecture's performance on “what” and “where” vision tasks is presented and compared with the performance of two multilayer networks. Finally, it is noted that function decomposition is an underconstrained problem, and, thus, different modular architectures may decompose a function in different ways. A desirable decomposition can be achieved if the architecture is suitably restricted in the types of functions that it can compute. Finding appropriate restrictions is possible through the application of domain knowledge. A strength of the modular architecture is that its structure is well suited for incorporating domain knowledge.  相似文献   

15.
In the present meta-analysis the effects of developmental level on the correlation between simple and complex span tasks were investigated. Simple span-complex span correlation coefficients presented in 52 independent samples (7,060 participants) were regressed on a variable representing mean age of sample (range: 4.96-22.80 years), using analyses adapted for meta-analytic purposes. The results showed strong positive relations between mean age of sample and simple span-complex span correlation coefficients, suggesting that the relation between simple and complex span tasks became stronger with increasing age. These results could not be accounted for by study-related differences in measurement reliability, restricted range, or sample size. A new theoretical account explaining these findings is outlined.  相似文献   

16.
Arndt  Michael 《Studia Logica》2020,108(3):509-547
Studia Logica - A calculus for classical propositional sequents is introduced that consists of a restricted version of the cut rule and local variants of the logical rules. Employed in the style of...  相似文献   

17.
The adenosine A(2A) receptor (A(2A)R) is highly enriched in the striatum where it is uniquely positioned to integrate dopaminergic, glutamatergic, and other signals to modulate cognition. Although previous studies support the hypothesis that A(2A)R inactivation can be pro-cognitive, analyses of A(2A)R's effects on cognitive functions have been restricted to a small subset of cognitive domains. Furthermore, the relative contribution of A(2A)Rs in distinct brain regions remains largely unknown. Here, we studied the regulation of multiple memory processes by brain region-specific populations of A(2A)Rs. Specifically, we evaluated the cognitive impacts of conditional A(2A)R deletion restricted to either the entire forebrain (i.e., cerebral cortex, hippocampus, and striatum, fb-A(2A)R KO) or to striatum alone (st-A(2A)R KO) in recognition memory, working memory, reference memory, and reversal learning. This comprehensive, comparative analysis showed for the first time that depletion of A(2A)R-dependent signaling in either the entire forebrain or striatum alone is associated with two specific phenotypes indicative of cognitive flexibility-enhanced working memory and enhanced reversal learning. These selective pro-cognitive phenotypes seemed largely attributed to inactivation of striatal A(2A)Rs as they were captured by A(2A)R deletion restricted to striatal neurons. Neither spatial reference memory acquisition nor spatial recognition memory were grossly affected, and no evidence for compensatory changes in striatal or cortical D(1), D(2), or A(1) receptor expression was found. This study provides the first direct demonstration that targeting striatal A(2A)Rs may be an effective, novel strategy to facilitate cognitive flexibility under normal and pathologic conditions.  相似文献   

18.
A well-established phenomenon in reasoning research is matching bias : a tendency to select information that matches the lexical content of propositional statements, regardless of the logically critical presence of negations. Previous research suggested, however, that the effect might be restricted to reasoning with conditional statements. This paper reports two experiments in which participants were required to construct or identify true and false cases of propositional rules of several kinds, including universal statements, disjunctions, and negated conjunctions. Matching bias was observed across all rule types but largely restricted to problems where participants were required to falsify rather than to verify the rules. A third experiment showed a similar generalization across linguistic forms in the Wason selection task with only if conditionals substituted for universals. The results are discussed with reference to contemporary theories of propositional reasoning.  相似文献   

19.
Using data which reflects upon the genetic makeup of patients, Cadoret, Woolson and Winokur (1977) test two theories regarding the genetic makeup of patients suffering from unipolar affective disorder. This hypothesis test is a good example of a problem in order restricted inference. Using some recently developed techniques in order restricted inference we analyze these data and compare the analyses.This research was sponsored by the Office of Naval Research under contract N00014-80-C-0321.  相似文献   

20.
A procedure is described which disrupts response-reinforcer contiguity and response dependency and which demonstrates how the location of the response dependency in interval schedules can be regarded as a controlling variable in its own right. Rats' lever pressing produced sucrose on a recycling conjunctive fixed-time 30-second fixed-ratio 1 schedule of reinforcement. Reinforcement occurred only at the end of the fixed-time component on this schedule and only if a response had occurred during that component. This produced a pause-respond-pause pattern during the interreinforcer interval for all animals. When the location of the response dependency was then restricted to a 10-second period in the middle of the fixed-time component, the pattern was accentuated and response rates increased for all animals, while postreinforcement pauses decreased sharply for two animals. When responding was required in the first 10 seconds of the fixed-time component, responding peaked earlier in the interval for all animals. Response rates were slightly below those in the previous conditions, while postreinforcement pauses were between 2 and 6 seconds across animals.  相似文献   

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