Contents: What is Simple Linear Regression? How to Find a Linear Regression Equation: How to Find a Linear Regression Equation by Hand. Find a Linear Regression Equation in Excel. TI83 Linear Regression. TI 89 Linear Regression Finding related items: How to Find the Regression Coefficient. Find the Linear Regression Slope. Find a Linear Regression Test … Read more
Contents: Coefficient of Determination (R Squared) What is the Adjusted Coefficient of Determination? Coefficient of Determination (R Squared) The coefficient of determination, R2, is used to analyze how differences in one variable can be explained by a difference in a second variable. For example, when a person gets pregnant has a direct relation to when … Read more
Correlation Coefficients > What is Zero-Order Correlation? Zero-order correlation indicates nothing has been controlled for or “partialed out” in an experiment. They are any correlation between two variables (X, Y) where no factor is controlled or held constant. If a third factor Z is controlled for, the correlation is first-order; If factors Z,A are controlled … Read more
Coefficient of Association > The contingency coefficient is a coefficient of association that tells whether two variables or data sets are independent or dependent of each other. It is also known as Pearson’s Coefficient (not to be confused with Pearson’s Coefficient of Skewness). It is based on the chi-square statistic, and is defined by: In … Read more
Statistics Definitions > The uncertainty coefficient, also called the entropy coefficient, or proficiency, is a measure of the entropy (that is, uncertainty) in a column variable Y which a row variable X explains. It is sometimes expressed in symbols as or U(X|Y) or U(C|R), where C is columns and R is rows. Disambiguation Note: Theil … Read more
Statistics Definitions > What is a Coefficient of Association? A Coefficient of Association measures the strength of a relationship. “Association” means that the variables have shared or common elements or some degree of agreement. A large number of different association coefficients is available. Which you choose is dependent on many factors, including the data type … Read more
Correlation Coefficient > Goodman and Kruskal’s lambda coefficient measures the proportional reduction in error in crosstab analysis. The statistic can be symmetric, where you do not have to specify which variable is dependent, and asymmetric where the dependent variable is specified. ε1 is the overall non-modal frequency and ε2 is the sum of the non-modal … Read more
Nonparametric data and tests > The gamma coefficient (also called the gamma statistic, or Goodman and Kruskal’s gamma) tells us how closely two pairs of data points “match”. Gamma tests for an association between points and also tells us the strength of association. The goal of the test is to be able to predict where … Read more
Statistics Definitions > Correlogram / Auto Correlation Function ACF Plot / Autocorrelation plot What is a Correlogram? A correlogram (also called Auto Correlation Function ACF Plot or Autocorrelation plot) is a visual way to show serial correlation in data that changes over time (i.e. time series data). Serial correlation (also called autocorrelation) is where an … Read more
Correlation Coefficients > Tetrachoric Correlation What is Tetrachoric Correlation? Tetrachoric correlation is used to measure rater agreement for binary data; Binary data is data with two possible answers—usually right or wrong. The tetrachoric correlation estimates what the correlation would be if measured on a continuous scale. It is used for a variety of reasons including … Read more