Guide to the T-Test: Decoding Data to Understand Behavior Why Statistics Matter in Therapy Imagine you have developed a new cognitive-behavioral intervention designed to reduce anxiety. You try it with a group of clients, and they seem to get better. But as a scientist-practitioner, you have to ask the hard question: Is this improvement real,
How to Create Dummy Variables in SPSS? By Ruben Geert van den Berg under Regression You can’t readily use categorical variables as predictors in linear regression: you need to break them up into dichotomous variables known as dummy variables.The ideal way to create these is our dummy variables tool. If you don’t want to use
Clustered Bar Chart over Multiple Variables By Ruben Geert van den Berg under Charts in SPSS Example Data VARSTOCASES without VARSTOCASES Restructuring the Data SPSS Chart Builder – Basic Steps Final Result This tutorial shows how to create the clustered bar chart shown below in SPSS. As this requires restructuring our data, we’ll first do
SPSS Chi-Square Test with Pairwise Z-Tests By Ruben Geert van den Berg under Chi-Square Tests Most data analysts are familiar with post hoc tests for ANOVA. Oddly, post hoc tests for the chi-square independence test are not widely used. This tutorial walks you through 2 options for obtaining and interpreting them in SPSS. Option 1
SPSS ANOVA without Raw Data By Ruben Geert van den Berg under ANOVA 1. Set Up Matrix Data File 2. SPSS Oneway Dialogs 3. Adjusting the Syntax 4. Interpreting the Output In SPSS, you can fairly easily run an ANOVA or t-test without having any raw data. All you need for doing so are the
Why There Are No P-Values in Nonlinear Regression: What to Use Instead Researchers often expect p-values alongside their coefficients in regression output. But in nonlinear regression, “no p-values” is often the rule, not the exception. This post explains why, and what statistics you should rely on instead. Introduction P-values are ubiquitous in many statistical analyses.
Empirical CDF (ECDF): Definition, Properties, Computation, and Applications In statistics, the cumulative distribution function (CDF) describes the probability that a random variable takes a value less than or equal to a given point. While theoretical CDFs rely on assumed distributions (such as normal or exponential), real data seldom follow a perfect model. The empirical cumulative
SPSS Missing Values Tutorial By Ruben Geert van den Berg under Basics Contents SPSS System Missing Values SPSS User Missing Values Setting User Missing Values Inspecting Missing Values per Variable SPSS Data Analysis with Missing Values What are “Missing Values” in SPSS? In SPSS, “missing values” may refer to 2 things: System missing values are
SPSS Multiple Linear Regression Example By Ruben Geert van den Berg under Regression Multiple Regression – Example Data Checks and Descriptive Statistics SPSS Regression Dialogs SPSS Multiple Regression Output Multiple Regression Assumptions APA Reporting Multiple Regression Multiple Regression – Example A scientist wants to know if and how health care costs can be predicted from
SPSS ANOVA with Post Hoc Tests By Ruben Geert van den Berg under ANOVA Contents Descriptive Statistics for Subgroups ANOVA – Flowchart SPSS ANOVA Dialogs SPSS ANOVA Output SPSS ANOVA – Post Hoc Tests Output APA Style Reporting Post Hoc Tests Post hoc tests in ANOVA test if the difference between each possible pair of