138 research outputs found
Estimating the false discovery risk of (randomized) clinical trials in medical journals based on published p-values
The influential claim that most published results are false raised concerns
about the trustworthiness and integrity of science. Since then, there have been
numerous attempts to examine the rate of false-positive results that have
failed to settle this question empirically. Here we propose a new way to
estimate the false positive risk and apply the method to the results of
(randomized) clinical trials in top medical journals. Contrary to claims that
most published results are false, we find that the traditional significance
criterion of produces a false positive risk of 13%. Adjusting
to .01 lowers the false positive risk to less than 5%. However, our
method does provide clear evidence of publication bias that leads to inflated
effect size estimates. These results provide a solid empirical foundation for
evaluations of the trustworthiness of medical research
Selecting applicants based on multiple ratings: Using binary classification framework as an alternative to inter-rater reliability
Inter-rater reliability (IRR) has been the prevalent quality and precision
measure in ratings from multiple raters. However, applicant selection
procedures based on ratings from multiple raters usually result in a binary
outcome. This final outcome is not considered in IRR, which instead focuses on
the ratings of the individual subjects or objects. In this work, we outline how
to transform the selection procedures into a binary classification framework
and develop a quantile approximation which connects a measurement model for the
ratings with the binary classification framework. The quantile approximation
allows us to estimate the probability of correctly selecting the best
applicants and assess error probabilities when evaluating the quality of
selection procedures using ratings from multiple raters. We draw connections
between the inter-rater reliability and the binary classification metrics,
showing that binary classification metrics depend solely on the IRR coefficient
and proportion of selected applicants. We assess the performance of the
quantile approximation in a simulation study and apply it in an example
comparing the reliability of multiple grant peer review selection procedures
Individual Professional Practice in the Company
Cílem této bakalářské práce je získání zkušeností z individuální odborné praxe poskytnuté firmou Martia a.s. sídlící v Ústí nad Labem probíhající během třetího roku studia na této škole.
Během odborné praxe jsem řešil mnoho úkolů z různých fází projekční práce. V této práci jsem vybral ty nejvýraznější, tedy:
• Kontrola kabelů pro pokládku
• Kontrola kabelů v dokumentaci
• Tvorba tabulky signálů
• Přeložky na Elektrárně MělníkThe aim of this bachelor thesis is to gain experience from individual professional practice provided by Martia a.s. based in Ústí nad Labem during the third year of study at this school.
During my internship, I solved many tasks from different stages of planner‘s work. In this work, I have selected the most significant ones, namely:
• Checking cables for installation
• Checking cables in documentation
• Signal table creation
• Relocations at the Mělník Power Plant420 - Katedra elektrotechnikyvelmi dobř
Narcissism: Theory, research and scales
The article focuses on psychological and sociological theories of narcissism. We draw on traditional authors like Freud, Kohut, Kernberg, Fromm and Horney, but we also focus on contemporary psychologists like J. Beck and Rhodewalt. Our main intention is to show narcissism not only as a psychological disorder, but primarily as a social phenomenon. Therefore, we mention authors of sociological theories of narcissism, such as Lash, Sennett, Lipovetsky and Giddens. Our text is also oriented to measuring narcissism as a cultural phenomenon. We analyse scores, results, limits and hypothesis of existing tests trying to summarize the most important findings in empirical research of social consequences of narcissism.The article focuses on psychological and sociological theories of narcissism. We draw on traditional authors like Freud, Kohut, Kernberg, Fromm and Horney, but we also focus on contemporary psychologists like J. Beck and Rhodewalt. Our main intention is to show narcissism not only as a psychological disorder, but primarily as a social phenomenon. Therefore, we mention authors of sociological theories of narcissism, such as Lash, Sennett, Lipovetsky and Giddens. Our text is also oriented to measuring narcissism as a cultural phenomenon. We analyse scores, results, limits and hypothesis of existing tests trying to summarize the most important findings in empirical research of social consequences of narcissism
Factors associated with cheating
Množství studií zkoumajících podvádění se v poslední době rychle rozrůstá. V návaznosti na to roste i počet teorií snažících se nečestné chování vysvětlit a rozličnost využívaných experimentálních designů. Tato práce objasňuje principy, na kterých tyto designy fungují a ukazuje na jejich silné a slabé stránky, popřípadě variace snažící se je překonat. Dále podává přehled aktuálních empirických poznatků doplněných o vyhodnocení jejich důvěryhodnosti. Následně využije všech těchto poznatků při navržení výzkumného projektu překonávajícího metodologické problémy předchozích výzkumů a zaměřujícího se na efekt s nedostatečnou empirickou podporou - vztah mezi spánkovou deprivací a nečestným chováním mediovaný pomocí vyčerpání. Klíčová slova Podvádění, nečestnost, spánková deprivaceThe number of studies investigating cheating has quickly grown in recent years. Followingly, the number of theories trying to explain the dishonest behavior and variance in experimental designs has increased as well. This thesis explains the principles on which the experimental designs are based, highlights their strengths and the weak sides and variations trying to get rid of them. In addition, it summarizes the current empirical findings with an assessment of their credibility. Furthermore, it makes use of the presented knowledge while proposing a study overcoming methodological issues of previous studies while focusing on effect with insufficient empirical support - a relationship between sleep deprivation and dishonest behavior mediated by depletion. Keywords Cheating, dishonesty, sleep deprivationDepartment of PsychologyKatedra psychologieFaculty of ArtsFilozofická fakult
The effects of pre- and post-partum depression on child behavior and psychological development from birth to pre-school age : a protocol for a systematic review and meta-analysis
Background: Pre- and post-partum depression is a common mood disorder with detrimental effects on both mother and child. The aim of the proposed review is to summarize evidence related to the effects of both pre- and post-partum depression on child behavior and development from birth to preschool age. In particular, our review will address mutual relations between pre- and post-partum depression in order to determine whether pre- and post-partum depression predict child psychological outcomes independently, whether there is an effect of timing of depression on child outcomes, whether pre- and post-partum depression interact to affect child outcomes, and whether the effect of pre-partum depression is mediated by depression after child's birth. Methods: We will include prospective longitudinal studies that report data about the effects of both pre- and post-partum depression on child psychological outcomes as published in peer-reviewed academic journals since January 1998. We will search EMBASE, MEDLINE, PsycARTICLES, PsycINFO, ISI Web of Science, Scopus, and Wiley Online databases to identify original research articles written in English. Two independent reviewers will screen search results in two stages: (i) titles and abstracts and (ii) full text. The first one will extract data into tables, while the latter will verify whether the data extracted are correct. We will assess the risk of bias in the selected studies using the Critical Appraisal Skills Programme (CASP), Cohort Study Checklist. The results of the review will be reported in a narrative form. If there are sufficient data available, a meta-analysis will be conducted using metaSEM package in R. Discussion: The proposed review will be the first systematic review summarizing the effects of both pre- and post-partum depression on child psychological development and behavior from birth to preschool age. The results of such a review may contribute to a better understanding of mutual relations between pre- and post-partum depression in their effects on child outcomes. They may also shed light on what periods in early human development are most vulnerable to the effects of maternal depression
Meta-analyses in psychology often overestimate evidence for and size of effects
Adjusting for publication bias is essential when drawing meta-analytic inferences. However, most methods that adjust for publication bias do not perform well across a range of research conditions, such as the degree of heterogeneity in effect sizes across studies. Sladekova et al. 2022 (Estimating the change in meta-analytic effect size estimates after the application of publication bias adjustment methods. Psychol. Methods) tried to circumvent this complication by selecting the methods that are most appropriate for a given set of conditions, and concluded that publication bias on average causes only minimal over-estimation of effect sizes in psychology. However, this approach suffers from a ‘Catch-22’ problem—to know the underlying research conditions, one needs to have adjusted for publication bias correctly, but to correctly adjust for publication bias, one needs to know the underlying research conditions. To alleviate this problem, we conduct an alternative analysis, robust Bayesian meta-analysis (RoBMA), which is not based on model-selection but on model-averaging. In RoBMA, models that predict the observed results better are given correspondingly larger weights. A RoBMA reanalysis of Sladekova et al.’s dataset reveals that more than 60% of meta-analyses in psychology notably overestimate the evidence for the presence of the meta-analytic effect and more than 50% overestimate its magnitude
Associations Between Mode of Birth and Neuropsychological Development in Children Aged 4 Years: Results from a Birth Cohort Study
The aim of this prospective longitudinal study was to examine the association between Cesarean section (CS) and child development and behavior. The sample consisted of 256 children who were born at term without serious perinatal pathologies. Their development and behavior was assessed at the age of four using Ages and Stages Questionnaire (ASQ-3), Children’s Behavior Questionnaire and Strength and Difficulties Questionnaire. Multivariate linear regression analyses were conducted to assess the association between CS and child outcomes. CS was associated with better scores in the Problem Solving domain of the ASQ in the whole sample. After stratifying by child sex, the positive association between CS and the Problem Solving domain was significant in boys, while no association was found in girls. Girls were rated less optimally in the Gross Motor domain of the ASQ when born via CS. Mode of birth was not associated with behavioral outcomes
Footprint of publication selection bias on meta-analyses in medicine, environmental sciences, psychology, and economics
Publication selection bias undermines the systematic accumulation of evidence. To assess the extent of this problem, we survey over 68,000 meta-analyses containing over 700,000 effect size estimates from medicine (67,386/597,699), environmental sciences (199/12,707), psychology (605/23,563), and economics (327/91,421). Our results indicate that meta-analyses in economics are the most severely contaminated by publication selection bias, closely followed by meta-analyses in environmental sciences and psychology, whereas meta-analyses in medicine are contaminated the least. After adjusting for publication selection bias, the median probability of the presence of an effect decreased from 99.9% to 29.7% in economics, from 98.9% to 55.7% in psychology, from 99.8% to 70.7% in environmental sciences, and from 38.0% to 29.7% in medicine. The median absolute effect sizes (in terms of standardized mean differences) decreased from d = 0.20 to d = 0.07 in economics, from d = 0.37 to d = 0.26 in psychology, from d = 0.62 to d = 0.43 in environmental sciences, and from d = 0.24 to d = 0.13 in medicine
Footprint of publication selection bias on meta-analyses in medicine, environmental sciences, psychology, and economics
Publication selection bias undermines the systematic accumulation of
evidence. To assess the extent of this problem, we survey over 68,000
meta-analyses containing over 700,000 effect size estimates from medicine
(67,386/597,699), environmental sciences (199/12,707), psychology (605/23,563),
and economics (327/91,421). Our results indicate that meta-analyses in
economics are the most severely contaminated by publication selection bias,
closely followed by meta-analyses in environmental sciences and psychology,
whereas meta-analyses in medicine are contaminated the least. After adjusting
for publication selection bias, the median probability of the presence of an
effect decreased from 99.9% to 29.7% in economics, from 98.9% to 55.7% in
psychology, from 99.8% to 70.7% in environmental sciences, and from 38.0% to
29.7% in medicine. The median absolute effect sizes (in terms of standardized
mean differences) decreased from d = 0.20 to d = 0.07 in economics, from d =
0.37 to d = 0.26 in psychology, from d = 0.62 to d = 0.43 in environmental
sciences, and from d = 0.24 to d = 0.13 in medicine
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