Cronbach’s Alpha in SPSS By Ruben Geert van den Berg under Factor Analysis Contents Cronbach’s Alpha – Quick Definition SPSS Cronbach’s Alpha Output Increase Cronbach’s Alpha by Removing Items Cronbach’s Alpha is Negative There are too Few Cases (N = 0) for the Analysis APA Reporting Cronbach’s Alpha Introduction A psychology faculty wants to examine
SPSS FACTOR Computes Wrong Covariances By Ruben Geert van den Berg under Factor Analysis Summary Wrong Covariances from FACTOR Correct Covariances from CORRELATIONS Correct Covariances from REGRESSION Summary When using pairwise exclusion of missing values, SPSS FACTOR computes wrong covariances. For correct covariances, use CORRELATIONS (menu or syntax) or REGRESSION (syntax only). This tutorial presents
How to Convert String Variables into Numeric Ones? By Ruben Geert van den Berg under SPSS Blog Introduction & Practice Data File Converting an SPSS string variable into a numeric one is simple. However, there’s a huge pitfall that few people are aware of: string values that can’t be converted into numbers result in system
Quick Overview SPSS Operators and Functions By Ruben Geert van den Berg under SPSS Blog The table below presents a quick overview of functions and operators in SPSS, sorted by type (numeric, string, …). Details and examples for some lesser known functions are covered below the table. TYPE Function DESCRIPTION EXAMPLE Comparison = (or EQ)
Z-Test and Confidence Interval Single Proportion By Ruben Geert van den Berg under Statistics A-Z Z-Test Assumptions Z-Test for Single Proportion – Formulas Continuity Correction for Z-Test Confidence Interval for Single Proportion Agresti-Coull Adjustment for CI A z-test for a single proportion examines if a population proportion is likely to be x. Example: does a
SPSS One-Way ANOVA Tutorial By Ruben Geert van den Berg under ANOVA For reading up on some basics, see ANOVA – What Is It? One-Way ANOVA – Null Hypothesis ANOVA Assumptions SPSS ANOVA Flowchart SPSS One-Way ANOVA Dialog SPSS ANOVA Output ANOVA – APA Reporting Guidelines ANOVA Example – Effect of Fertilizers on Plants A
SPSS Paired Samples T-Test Tutorial By Ruben Geert van den Berg under Statistics A-Z & T-Tests A paired samples t-test examines if 2 variables are likely to have equal population means. Paired Samples T-Test Assumptions SPSS Paired Samples T-Test Dialogs Paired Samples T-Test Output Effect Size – Cohen’s D Testing the Normality Assumption Example A
SPSS Hierarchical Regression Tutorial By Ruben Geert van den Berg under Regression Hierarchical regression comes down to comparing different regression models. Each model adds 1(+) predictors to the previous model, resulting in a “hierarchy” of models. This analysis is easy in SPSS but we should pay attention to some regression assumptions: linearity: each predictor has
SPSS Z-Test for Independent Proportions Tutorial By Ruben Geert van den Berg under Nonparametric Tests Z-Test – Assumptions SPSS Z-Tests Dialogs SPSS Z-Test Output SPSS Z-Tests – Strengths & Weaknesses APA Reporting Z-Tests A z-test for independent proportions tests if 2 subpopulations score similarly on a dichotomous variable. Example: are the proportions (or percentages) of
What Is a String Variable? Meaning, Examples, and Use in Data Analysis In research and data analysis, especially when using statistical software like SPSS, R, or Python, understanding the different types of variables is essential. One of the foundational variable types is the string variable. This blog explains what a string variable is, how it