# Statistics

Introduction To Statistics

An introduction to statistics for sociology.

Statistical Terms You Should Know

Some of the major statistical terms used in sociology journals and texts.

Levels of Measurement

Level of measurement refers to the way that a variable is measured. There are four main levels of measurement that variables can have: nominal, ordinal, interval, and ratio.

Descriptive vs. Inferential Statistics

Statistical procedures can be divided into two major categories: descriptive statistics and inferential statistics. This article discusses the differences between the two.

Measures of Central Tendency

Measures of central tendency are numbers that describe what is average or typical of the distribution of data. There are three main measures of central tendency: mean, median, and mode.

Normal Distribution

A normal distribution is a theoretical idea that is based on theory rather than real data. Normal distributions are typically the goal and the ideal in research and data and something that every researcher strives for.

Confidence Intervals And Confidence Levels

A confidence interval is a measure of estimation. It is an estimated range of values that is likely to include the population parameter being calculated. A confidence level is a measure of how accurate the confidence interval is.

Variance and Standard Deviation

Variance and standard deviation are two closely related measures of variation that you will hear a lot in studies, journals, or statistics class. They are two basic and fundamental concepts in statistics that must be understood in order to understand most other statistics concepts or procedures.

Crosstabulations

Crosstabs are a great way to familiarize yourself with the data you are working with and to get a rough idea of how the variables in your data set are related, if at all. Crosstabs are useful for exploring the data, exploring relationships in your data, and determining future analyzes.

Correlation Analysis

Correlation analysis is useful for determining the direction and strength of a relationship between two variables.

Logistic Regression

Logistic regression is a common statistical technique used in sociological studies. It provides a method for modeling a binary response variable, which takes values 0 and 1.

Analysis of Variance (ANOVA)

Analysis of Variance, or ANOVA for short, is a statistical test that looks for significant differences between means.

Linear Regression Analysis

Linear regression is a statistical technique that is used to learn more about the relationship between an independent (predictor) variable and one or more dependent (criterion) variables.

Principal Components and Factor Analysis

Principal components analysis (PCA) and factor analysis (FA) are statistical techniques used for data reduction or structure detection.

Structural Equation Modeling

Structural equation modeling is an advanced statistical technique that has many layers and many complex concepts. This article provides a very general overview of the method.

Survival Analysis

Survival analysis, also known as event history analysis, is a class of statistical methods for studying the occurrence and timing of events. These methods are most often applied to the study of deaths, however they are also extremely useful in studying many different kinds of events in both the social and natural sciences.

Presenting Data in Graphic Form

Graphs tell a story with visuals rather than in words or numbers and can help readers understand the substance of the findings rather than the technical details behind the numbers. Learn about the different types of graphs used in social science research.

Cluster Analysis

Researchers are often looking for ways to organize observed data into meaningful structures or classifications. Cluster analysis is one way to do that.

Lambda and Gamma

Lambda and gamma are two measures of association that are commonly used in social science statistics and research. Lambda is used for nominal variables while gamma is used for ordinal variables.

Index of Qualitative Variation (IQV)

The index of qualitative variation (IQV) is a measure of variability for nominal variables, such as race, ethnicity, or gender. It is based on the ratio of the total number of differences in the distribution to the maximum number of possible differences within the same distribution. Learn more about the IQV, including how to calculate it.