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Methodological innovations in psychological research
Frollová, Nikola ; Vranka, Marek (advisor) ; Fabianová, Ivana (referee)
The year 2012 opened an intense debate about the methodological problems of psychological research that lead to excessive publication of unreliable and nonreplicable results. The proposed improvements consist of conducting more replication studies, sharing data openly, limiting the "degrees of researcher freedom ", and improving the understanding and application of statistical methods for data analysis. This bachelor thesis aims to map the aforementioned problems, proposed solutions, as well as possible criticisms and problems with their implementation in practice. The research proposal consists of measuring the prevalence of questionable scientific practices among psychologists in Czech Republic.
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Price Elasticity of Water Demand: A Meta-Analysis
Thoma, Richard ; Havránek, Tomáš (advisor) ; Janotík, Tomáš (referee)
Meta-analysis is a statistical method that allows us to combine results of em- pirical research. A theoretical summary helped to select appropriate model for the empirical part of this thesis - a meta-analysis focused on the price elas- ticity of residential water demand. A mixed-effects multilevel model, which corrects for selection bias, heteroskedasticity and within-study correlation, was employed. Publication bias was found only for subsample excluding data from the western part of the United States. Heckman meta-regression shows that the true price elasticity of water demand is -0,246. Finally variation in results across studies is explained. Using average price instead of margi- nal, the discrete-continuous choice model and data from the western part of the United States for water demand modelling will result in higher values of estimated elasticity. 1
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The Interest Elasticity of Money Demand: A Meta-Analysis
Slouková, Eliška ; Havránek, Tomáš (advisor) ; Holub, Tomáš (referee)
Even though precise evaluation of money demand function is essential for cen- tral banking and for the right determination of the transmission mechanism, economists have not reached a consensus about the underlying determinants of money demand function neither their magnitude and direction. Researchers differ even in the selection of measures used for the main variables - income, and interest rate. While the heterogeneity in elasticity estimates of the former one has been scrutinize in several quantitative surveys, to the best of our knowledge, there has not been compiled any meta-analysis focusing on differences among the interest rate elasticities of the money demand. Therefore, we collected 53 studies reporting 1 094 estimates of interest rate elasticity. Implementing both the state-of-the-art methods and those proposed only recently, we have found out that researches are prone to selective reporting. Firstly, our results shows that negative publication bias is present in empirical studies of the money de- mand and increases the average elasticity estimate approximately three times (in absolute terms). Secondly, negative highly precise estimates are more likely to be compared to their imprecise counterparts. Additionally, we scrutinize po- tential sources of heterogeneity among individual...
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Islam and Economic Performance: A Meta-Analysis
Kratochvíla, Patrik ; Havránek, Tomáš (advisor) ; Schwarz, Jiří (referee)
Islam and Economic Performance: A Meta-Analysis Patrik Kratochvíla June 28, 2021 Abstract The ongoing economic supremacy of the West has prompted debates on the ability of non-Christian religions to generate economic growth. The academic literature focusing on the Islamic religion o↵ers multiple answers, leaving the matter unresolved and with no definite conclusion. Based on a quantitative sur- vey of 315 estimates collected from 41 relevant academic studies, Islam exerts a positive and statistically significant e↵ect on economic growth in 40% of cases, a negative and statistically significant e↵ect in 10% of cases, and virtually zero e↵ect in 50% of cases. Tests for publication bias indicate slightly preferential reporting against negative estimates. When I correct for this bias, I find that the mean e↵ect of Islam on economic growth is positive but economically small. I also construct 79 moderator variables capturing methodological heterogeneity among the primary studies and apply the method of Bayesian model averaging to deal with model uncertainty in meta-analysis. The analysis shows that the heterogeneity in the results is primarily driven by di↵erences in the sample com- position and the choice of control variables, and to a lesser extent by estimation characteristics and proxies for Islam employed. 1
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Income Inequality and Happiness: A Meta-Analysis
Kamenická, Lucie ; Havránková, Zuzana (advisor) ; Chytilová, Julie (referee)
The relationship between income inequality and happiness is central to a host of welfare policies. If higher income inequality puts people down, advocating for income redistribution from the rich to the poor could make society happier. We show, however, that this popular consensus on the relationship's direction is rather absent in the academic literature. Based on the 868 observations col- lected from 53 studies and controlling for 62 aspects of study design, we use state-of-the-art meta-analysis techniques to identify several important drivers of the efect. Unless each study gets the same weight, the literature is driven by publication bias pushing the estimates against the popular consensus. While geographical diferences dominate among the systematic infuences of the re- lationship's magnitude, the relationship is also strongly afected by various methods and data the authors use in the primary studies. Most prominently, it matters if authors control for diferent individual's characteristics, such as perceived trust in people or their health status.
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The Impact of Student Employment on Educational Outcomes: A Meta-Analysis
Kroupová, Kateřina ; Havránek, Tomáš (advisor) ; Schwarz, Jiří (referee)
Despite the extensive body of empirical research, the discussion on whether student employment impedes or improves educational outcomes has not been resolved. Using meta-analytic methods, we conduct a quantitative review of 861 effect estimates collected from 69 studies describing the relationship between student work experience and academic performance. After outlining the theo- retical mechanisms and methodological challenges of estimating the effect, we test whether publication bias permeates the literature concerning educational implications of student employment. We find that researchers report negative estimates more often than they should. However, this negative publication bias is not present in a subset of studies controlling for the endogeneity of student decision to take up employment. Furthermore, after correcting for the negative publication bias, we find that the student employment-education relationship is close to zero. Additionally, we examine heterogeneity of the estimates using Bayesian Model Averaging. Our analysis suggests that employment intensity and controlling for student permanent characteristics are the most important factors in explaining the heterogeneity. In particular, working long hours re- sults in systematically more negative effect estimates than not working at...
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Essays in Applied Meta-Analysis
Polák, Petr ; Havránek, Tomáš (advisor) ; Pugh, Geoff (referee) ; Rusnák, Marek (referee) ; Reed, William Robert (referee)
The dissertation consists of three papers presenting applications of meta-analysis in economics and introductory chapter which discusses the development of meta-analysis in author's perspective as well as strengths and weaknesses of this quantitative method to synthesize empirical research. In the first paper analyses the impact of information and communication technology investments on productivity. The second paper focuses on the trade effect of the euro. In the third investigates the relation between international trade flows and trade costs.
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Trading volume and expected stock returns: a meta-analysis
Bajzík, Josef ; Havránek, Tomáš (advisor) ; Červinka, Michal (referee)
I investigate the relationship between expected stock returns and trading volume. I collect together 522 estimates from 46 studies and conduct the first meta-analysis in this field. Use of Bayesian model averaging and Frequentist model averaging help me to discover the most influential factors that affect the return-volume relationship, since I control for more than 50 differences among primary articles such as midyear and type of data, length of the primary dataset, size of market, or model employed. In the end, I find out that the relation between expected stock returns and trading volume is rather negligible. On the other hand, the contemporaneous relation between returns and volume is positive. These two findings cut the mixed results from previously written studies. Moreover, the investigated relationship is influenced by the size of country of interest and the level of its development. Besides the primary studies that employ higher data frequency provide substantially larger estimates than the studies with data from longer time periods. On the contrary, there is no difference among different estimation methodologies used. Finally, I employ classical and modern techniques such as stem-based methodology for publication bias detection, and I find evidence for it in this field. 1
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