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Statistical Analysis in JASP

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DOI: 10.6084/m9.figshare.9980744 4th Edition JASP v0.14 2020 Copyright © 2020 by Mark A Goss-Sampson. Licenced as CC BY 4.0 All rights reserved. This book or any portion thereof may not be reproduced or used in any manner whatsoever without the express written permission of the author except for research, education or private study. CONTENTS PREFACE .................................................................................................................................................. 1 USING THE JASP ENVIRONMENT ............................................................................................................ 2 DATA HANDLING IN JASP ........................................................................................................................ 8 JASP ANALYSIS MENU ........................................................................................................................... 11 DESCRIPTIVE STATISTICS ....................................................................................................................... 14 DESCRIPTIVE PLOTS IN JASP .............................................................................................................. 19 SPLITTING DATA FILES ....................................................................................................................... 23 EXPLORING DATA INTEGRITY ................................................................................................................ 25 DATA TRANSFORMATION ..................................................................................................................... 34 EFFECT SIZE ........................................................................................................................................... 38 ONE SAMPLE T-TEST ............................................................................................................................. 40 BINOMIAL TEST ..................................................................................................................................... 43 MULTINOMIAL TEST .............................................................................................................................. 46 CHI-SQUARE ‘GOODNESS-OF-FIT’ TEST............................................................................................. 48 MULTINOMIAL AND Χ2 ‘GOODNESS-OF-FIT’ TEST. ........................................................................... 49 COMPARING TWO INDEPENDENT GROUPS .......................................................................................... 50 INDEPENDENT T-TEST ....................................................................................................................... 50 MANN-WITNEY U TEST ..................................................................................................................... 54 COMPARING TWO RELATED GROUPS ................................................................................................... 56 PAIRED SAMPLES T-TEST ................................................................................................................... 56 WILCOXON’S SIGNED RANK TEST...................................................................................................... 59 CORRELATION ANALYSIS ....................................................................................................................... 61 REGRESSION .......................................................................................................................................... 67 SIMPLE REGRESSION ......................................................................................................................... 70 MULTIPLE REGRESSION ..................................................................................................................... 73 LOGISTIC REGRESSION .......................................................................................................................... 80 COMPARING MORE THAN TWO INDEPENDENT GROUPS .................................................................... 85 ANOVA .............................................................................................................................................. 85 KRUSKAL-WALLIS .............................................................................................................................. 92 COMPARING MORE THAN TWO RELATED GROUPS ............................................................................. 95 RMANOVA ......................................................................................................................................... 95 FRIEDMAN’S REPEATED MEASURES ANOVA .................................................................................. 100 COMPARING INDEPENDENT GROUPS AND THE EFFECTS OF COVARIATES ........................................ 103 ANCOVA .......................................................................................................................................... 103 TWO-WAY INDEPENDENT ANOVA ...................................................................................................... 111 TWO-WAY REPEATED MEASURES ANOVA ........................................................................................ 119 MIXED FACTOR ANOVA ....................................................................................................................... 127 CHI-SQUARE TEST FOR ASSOCIATION ................................................................................................. 135 META-ANALYSIS .................................................................................................................................. 142 EXPERIMENTAL DESIGN AND DATA LAYOUT IN EXCEL FOR JASP IMPORT. ........................................ 150 Independent t-test .......................................................................................................................... 150 Paired samples t-test ...................................................................................................................... 151 Correlation ...................................................................................................................................... 152 Logistic Regression .......................................................................................................................... 154 One-way Independent ANOVA ....................................................................................................... 155 One-way repeated measures ANOVA ............................................................................................. 156 Two-way Independent ANOVA ....................................................................................................... 157 Two-way Repeated measures ANOVA ............................................................................................ 158 Two-way Mixed Factor ANOVA ....................................................................................................... 159 Chi-squared - Contingency tables ................................................................................................... 160 SOME CONCEPTS IN FREQUENTIST STATISTICS .................................................................................. 161 WHICH TEST SHOULD I USE? ............................................................................................................... 165 Comparing one sample to a known or hypothesized population mean. ........................................ 165 Testing relationships between two or more variables ................................................................... 165 Predicting outcomes ....................................................................................................................... 166 Testing for differences between two independent groups ............................................................ 166 Testing for differences between two related groups ..................................................................... 167 Testing for differences between three or more independent groups ............................................ 167 Testing for differences between three or more related groups ..................................................... 168 Test for interactions between 2 or more independent variables ................................................... 168 PREFACE JASP stands for Jeffrey’s Amazing Statistics Program in recognition of the pioneer of Bayesian inference Sir Harold Jeffreys. This is a free multi-platform open-source statistics package, developed and continually updated by a group of researchers at the University of Amsterdam. They aimed to develop a free, open-source programme that includes both standard and more advanced statistical techniques with a major emphasis on providing a simple intuitive user interface. In contrast to many statistical packages, JASP provides a simple drag and drop interface, easy access menus, intuitive analysis with real-time computation and display of all results. All tables and graphs are presented in APA format and can be copied directly and/or saved independently. Tables can also be exported from JASP in LaTeX format JASP can be downloaded free from the website https://jasp-stats.org/ and is available for Windows, Mac OS X and Linux. You can also download a pre-installed Windows version that will run directly from a USB or external hard drive without the need to install it locally.
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