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It is well known that most of the standard specification tests are not valid when the alternative hypothesis is misspecified. This is particularly true in the error component model, when one tests for either random effec...

This paper derives unbalanced versions of the tests statistics for first order serial correlation and random individual e®ects summarized in Sosa Escudero and Bera (2001), and updates their xttest1 routine. The derived ...

The traditional view of colonization of the Americas as a migration across Beringia and subsequent dispersal southward following the last glacial maximum is being increasingly questioned. In North America, archaeological...

Metronidazole (MTZ) is a wonderful drug, which is used clinically to treat a wide range of bacterial and protozoal infections. This study aimed to achieve a precise characterization of the cytotoxic and genotoxic activit...

Although octyldodecanol has been used for several decades as an ingredient for emulsions, no required Hydrophilic-Lipophilic Balance (HLB) values for this alcohol were found in the literature. The purpose of this paper...

One of the frequent questions by users of the mixed model function lmer of the lme4 package has been: How can I get p values for the F and t tests for objects returned by lmer? The lmerTest package extends the 'lmerMod' ...

A general formula ( α ) of which a special case is the Kuder-Richardson coefficient of equivalence is shown to be the mean of all split-half coefficients resulting from different splittings of a test. α is therefore an...

Construct Validity in Psychological TestsVALIDATION of psychological tests has not yet been adequately concep tua1ized, as the APA Committee on Psychological Tests learned when it undertook to specify what qualities shou...

This paper presents specification tests that are applicable after estimating a dynamic model from panel data by the generalized method of moments, and studies the practical performance of these procedures using both gene...

Matricaria recutita L. (Asteraceae), better known as chamomile, has been used due to its pharmacological properties. Laboratory-manufactured gels with chamomile extract were developed with the evaluation of the physical-...

Background: Clinical examinations increasingly consist of composite tests to assess all aspects of the curriculum recommended by the General Medical Council. Setting: A final undergraduate medical school examination for...

BACKGROUND: A short battery of physical performance tests was used to assess lower extremity function in more than 5,000 persons age 71 years and older in three communities. METHODS: Balance, gait, strength, and enduranc...

Abstract Hypothesis‐testing methods for multivariate data are needed to make rigorous probability statements about the effects of factors and their interactions in experiments. Analysis of variance is particularly powe...

The relationship between co-integration and error correction models, first suggested in Granger (1981), is here extended and used to develop estimation procedures, tests, and empirical examples. If each element of a vect...

Abstract Mixture modeling is a widely applied data analysis technique used to identify unobserved heterogeneity in a population. Despite mixture models' usefulness in practice, one unresolved issue in the application of ...

This paper proposes new tests for detecting the presence of a unit root in quite general time series models. Our approach is nonparametric with respect to nuisance parameters and thereby allows for a very wide class of w...