Four mediation models of teacher expectancy effects on students’ outcomes in mathematics and literacy

The study tested 4 direct and 28 indirect teacher expectancy effects on students’ results in the mathematics and literacy sections of the matriculation test, and their final marks in the 12th-grade mathematics and literacy class. The following were considered as mediators: student self-esteem, their self-expectancy, and time spent learning mathematics and literacy. The study involved 1374 first year college students. Conducted path analyses revealed: (1) the total teacher expectancy effects was the strongest for final marks in mathematics, followed by test results in mathematics, test results in literacy, and final marks in literacy; (2) the direct effect was stronger than the total indirect teacher expectancy effects in the case of mathematics, while for literacy outcomes, the order of the effects was reversed; (3) the direct teacher expectancy effects were positive; the indirect effects reversed after including student self-esteem/student self-expectancy into relations between teachers’ expectancy and mathematics and literacy outcomes; (4) teachers’ expectancy was mediated most strongly by student self-esteem, time spent learning, and student self-expectancy, or by student self-expectancy and time spent learning, respectively for mathematics and literacy outcomes; (5) the impact of teachers’ expectancy was stronger than student self-expectancy for mathematics, but was the same or weaker for literacy outcomes, respectively. The obtained results were discussed in the light of the theory and results of studies concerning teacher expectancy effects.     

The Polish adaptation of the Early Childhood Behavior Questionnaire (ECBQ): Psychometric properties,age and gender differences and convergence between the questionnaire and the observational data

The main aim of the study was to determine the psychometric properties of the version of the Early Childhood Behavior Questionnaire (ECBQ) adapted to Polish culture. Since temperament in toddlers was being observed in a laboratory, an external validity of the ECBQ was also provided. Kagan’s observational paradigm was used to test 215 18-month-old children. Their parents completed the ECBQ twice, when the children were 26 and 30 months old. The results showed good internal consistency and confirmed the longitudinal stability of the scale. The same three-factor solution was found in the structure of the scale as in the original American study. The convergence between the observational and parent report data supported the ECBQ’s external validity. Similarities in the structure of the scale observed between the Polish and American data are discussed from a cross-cultural perspective. The usefulness of the Polish ECBQ and the limitations of the obtained results are discussed.     

Prototetyka St. Lesniewskiego

Streszczenie Prototetyka St. Len'ewskiego jest uogólnieniem dwuwartociowego rachunku zda. Wystpuj w niej obok terminów tego rachunku funktory (zarówno stae jak i zmienne) tych wszystkich kategorii semantycznych, jakie mog by zdefiniowane, gdy punktem wyjcia jest kategor a zda.W pracy zreferowane s trzy systemy prototetyki. Terminem pierwotnym dwu z nich jest implikacja, terminem pierwotnym systemu trzeciego jest równowano. Systemy o terminie pierwotnym implikacji róni s. reguami wnioskowania. W jednym z nich obowizuje regua weryfikacji, w drugim regua ekstensjonalnoci. Pierwsza z tych regu jest uogólnieniem nastpujcej reguy rachunku zda, wzbogaconego o terminy 0 i 1:Wyraenie jest tez systemu, gdy tezami systemu s oba wyraenia powstae z przez podstawienie za pewn jego zmienn symboli 0 i 1.W myl reguy ekstensjonalnoci tezami systemu s prawa ekstensjonalnoci, sformuowane dla funktorów dowolnych kategorii semantycznych wac-wych prototetyce.W pracy podaj dowody równowanoci trzech systemów prototetyki i dowód ich zupenoci.Znaczna cz wyników Leniewskiego, zreferowanych w pracy, nie bya dotd opublikowana. Opracowujc te wyniki opieraem si na notatkach z wykadów Leniewskiego, spisanych przez jego uczniów. Oryginalne notatki Leniewskiego ulegy zniszczeniu w czasie powstania warszawskiego.     

О правилах исчисления предложе ий

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Evaluation of drug toxicity in clinical trials

An increasing number of drugs removed from the market because of unacceptable toxicity raises concerns regarding preapproval testing of drug safety. In the present paper it is postulated that the non-inferiority type of trial should be abandoned in favor of the superiority trial with active controls and less stringent (p<0.1, both for efficacy and toxicity) statistics. This approach will increase sensitivity of detection of drug-induced adverse effects at the expense of increasing false positive results regarding the difference in efficacy between the tested and reference drug. Such a move will increase the protection of future patients. In addition, the proposed design is far more acceptable from the clinical (e.g. no need to specify the statistically expected “unimportant” number of deaths) and ethical points of view, as well as being favored by the strong incentive of involved parties. In the second part of this paper arguments are presented in favor of the hypothesis that placebo (still used in some superiority trials) does not induce adverse effects. The assertion that placebo may induce adverse effects is probably biased by the nature of the clinical experiment. Such a conclusion is supported by studies indicating that placebo-induced adverse effects are disease — and treatment — specific. The modification of clinical trials according to the proposed changes may increase the trials’ sensitivity at detecting adverse effects of drugs. A lecture on the subject of this paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005.     

On field's argument for substantivalism

In this article I subject to criticism Field's argument, according to which field theory takes space‐time to be à substance since it ascribes field properties to space‐time points. There is petitio principii error made in this reasoning because Field does not give any justification for his controversial assumption that fields are properties of space‐time points. What is more, I suggest, Field's interpretation of field theory is incompatible with the way this theory is understood and utilized by its users, namely scientists. My criticism is based on the assumption that one cannot propose an ontology of a given scientific theory, at the same time imposing on it an interpretation which clashes with the interpretation current among its users. I also suggest that in order to establish the ontology of a scientific theory one should also take into account the way it has been constructed. According to this criterion, field theory does indeed take space‐time to be a substance.     

Approximative truth of fact-statements,laws, and theories

Summary The paper is a sketch of a conception of approximative truth (or verisimilitude). The concepts of relative error, and degree of inadequacy are introduced. By means of them the concept of truth-content of quantitative facts-statements, laws and theories is defined. Laws and theories accepted in science have a high truth-content, i.e. they are approximately true.