Key Terms Flashcards
(17 cards)
What does Multiple R mean in regression statistics?
The correlation coefficient between the observed and predicted values of the dependent variable, ranging from -1 to 1.
What is R Square (R²)?
The coefficient of determination that represents the proportion of variance in the dependent variable explained by the independent variables, ranging from 0 to 1.
What is the purpose of Adjusted R Square?
A modified version of R² that adjusts for the number of predictors in the model to prevent overestimation of model fit.
What does Standard Error measure in regression analysis?
The standard deviation of the residuals (errors), indicating the typical distance between actual and predicted values.
What does the term ‘Observations’ refer to in regression statistics?
The total number of data points (rows) used in the regression analysis.
What does df stand for in the context of the ANOVA table and what does it represent?
Degrees of Freedom, which represents the number of values in the final calculation that are free to vary.
What is the Sum of Squares (SS) in the ANOVA table?
A measure of total variation, partitioned into regression SS (explained by the model) and residual SS (unexplained/error).
How is Mean Square (MS) calculated in the ANOVA table?
By dividing SS by the corresponding degrees of freedom (df).
What does the F-statistic indicate in regression analysis?
A ratio of mean regression variance to mean error variance, used to test if the overall regression model is statistically significant.
What does a small Significance F value suggest?
It indicates the probability that the observed F occurred by chance. A value typically < 0.05 suggests the model is statistically significant.
What does a Coefficient represent in the coefficients table?
Indicates how much the dependent variable changes per unit change in the predictor.
- The estimated effect of a predictor variable on the dependent variable,
What is the significance of Standard Error in the coefficients table?
The standard deviation of the coefficient estimate; smaller values indicate more precise estimates.
What does t Stat measure?
The t-value for testing whether a coefficient is significantly different from zero, calculated as Coefficient ÷ Standard Error.
What does the P-value represent in regression analysis?
The probability that the observed t-statistic would occur by chance if the true coefficient were zero; a small value typically < 0.05 indicates significance.
What is included in the 95% Confidence Interval for a coefficient?
The range within which the true population coefficient is expected to fall with 95% confidence.
Fill in the blank: A higher F-statistic usually indicates a _______.
better model
True or False: Adjusted R Square can increase when more predictors are added to the model.
False
