== Questions about p-values, significance or power of tests ==

 1. [[FAQ/pilot| Can I combine pilot data with main study data?]]

 1. [[FAQ/onesp| When and how do I evaluate a one-sided p-value and quote a one-sided 95% confidence interval?]]

 1. [[FAQ/powtabs| What sample sizes do I need for doing tests with a given power?]] 

 1. [[FAQ/effectSize| A guide to magnitudes of effect sizes]]

 1. [[FAQ/prep| Problems using p-rep, the Probability of Replication]]

 1. [[FAQ/dunlap| A quick guide to choice of sample sizes for Cohen's effect sizes]]

 1. [[FAQ/comparezt|A note on comparing z and t statistics and their p-values?]]

 1. [[FAQ/td| How do I convert a t-statistic (and an Odds Ratio) into an effect size?]]

 1. [[FAQ/cd| How do I compute Cohen's d in SPSS and EXCEL and its and eta-squared confidence interval in SPSS, R or EXCEL?]]

 1. [[FAQ/hedgeg| How do I compute Hedge's g from Cohen's d?]]

 1. [[FAQ/mse| How do I compute Mean Square Error (MSE) in EXCEL or SPSS?]]

 1. [[FAQ/effcis| A guide to obtaining confidence intervals for effect sizes]]

 1. [[FAQ/Escomp| How do I compute effect sizes (including variance adjusted ones)?]]

 1. [[FAQ/powprogs|How do I do power calculations in SPSS, R, EXCEL and using web freeware?]]

 1. [[FAQ/powposi|How do I do power (sample size) calculations on Poisson counts?]]

 1. [[FAQ/pownp| How do I do power calculations for sign test and one sample Wilcoxon test?]]

 1. [[FAQ/studyN| General rules of thumb for sample sizes in pilot studies]]

 1. [[attachment:senspN.xls|How do I work out sample size for apriori specificities and sensitivities?]]

 1. [[FAQ/equival|How do I compute statistical tests of equivalence?]]

 1. [[FAQ/SPSSpow|Computing Power for ANOVAs using the SPSS GLM procedure]]

 1. [[attachment:MANpow.pdf|Computing Power for ANOVAs using the SPSS MANOVA procedure]]

 1. [[FAQ/FDR|How do I do False Discovery Rate (FDR) corrections for multiple tests?]] 

 1. [[FAQ/Bayes|How do I calculate and interpret conditional probabilities?]]

 1. [[FAQ/pvalsdef|What is a p-value?]]

 1. [[FAQ/pvalues|How do I find p-values using critical values as input in SPSS and EXCEL?]]

 1. [[FAQ/pvs|How do I adjust p-values for number of comparisons using SPSS and R?]] 

 1. [[FAQ/SpssBonferroni|Adjusted p-values]]

 1. [[FAQ/CombiningPvalues|Combining p-values by Fisher's and Stouffer's methods]]

 1. [[FAQ/CombiningZandT|Summing z values and summing t-values]]

 1. [[FAQ/Fdfs|Why does the value of one in the F distribution have a p-value which is less than 1?]]