Observers completed perceptual categorization tasks in which base rates and payoffs were manipulated separately or simultaneously across a range of category discriminabilities. Decision criterion estimates from the simultaneous base-rate/payoff conditions were closer to optimal than those predicted from the independence assumption, in line with predictions from the flat-maxima hypothesis. A hyb...

A Monte Carlo computer simulation was used to evaluate the effect on the Type I error rate when the assumption of independence was not met in the two-sample t test. It was shown that when there is a positive correlation within groups the nominal alpha level is considerably smaller than the probability of the Type I error rate. This study used five values of ! and 19 different "’s, computing 1,0...

Cybersickness assessment is predominantly conducted via the Simulator Sickness Questionnaire (SSQ). Literature has highlighted that assumptions which are made concerning baseline may be incorrect, especially assumption healthy participants enter with no or minimal associated symptoms. An online survey study was to explore further this amongst a general population sample ( N = 93). Results for s...

The software engineering literature contains many studies of the efficacy of fault finding techniques. Few of these, however, consider what happens when several different techniques are used together. We show that the effectiveness of such multitechnique approaches depends upon quite subtle interplay between their individual efficacies and dependence between them. The modelling tool we use to s...

Most accounts of categorization assume the categorization decision for an item to be independent of the categorization decisions for other items. A number of methods are brought to bear on the question of whether this assumption is justified. These methods involve the application of a formal categorization model that explicitly incorporates the independence assumption to categorization data and...

There has been a long-standing controversy in epidemiology with regard to an appropriate risk scale for testing interactions between genes (G) and environmental exposure (E ). Although interaction tests based on the logistic model-which approximates the multiplicative risk for rare diseases-have been more widely applied because of its convenience in statistical modeling, interactions under addi...

The method of generalized estimating equations (GEE) is a popular tool for analysing longitudinal (panel) data. Often, the covariates collected are time-dependent in nature, for example, age, relapse status, monthly income. When using GEE to analyse longitudinal data with time-dependent covariates, crucial assumptions about the covariates are necessary for valid inferences to be drawn. When tho...

the present research aims to analyze the orthographic errors of german-speaking learners of persian at the elementary level. to do so, pieces of writing of 34 students were gathered via self-motivated method and examined based on the corpus of orthographic errors, using the frameworks proposed by keshavarz (1994) and ziahoseini (1999). 850 phonological, morphological, and orthographical errors ...