In: Statistics and Probability
Discuss the statistics that must be evaluated when reviewing the regression analysis output. Provide examples of what the values represent and an explanation of why they are important.
A regression analysis says whether the predicted variable changes with the dependent variable . In regression the analysis always direct to the evaluation of the R square , F test interpretation of beta variable and finally the regression equation .
When the regression is conducted an F value and significance level of F value is calculated if the F value is statistically significant the model explains a significant amount of variance in the outcome variable . Regularly the value is significant when p<0.05 .Like this a R2 value is also calculated it can be indicated as the percent of variance in the outcome variable that is explained by a predicted variable . After these it is important to obtain the beta variable it can be negative or positive and have a t value . The beta variable is the degree of change of outcome variable for every 1 unit of change in prediction variables .If beta coefficient is negative then every 1 unit increase in the prediction variable the outcome variable will decrease by the beta value . Also if the beta coefficient is positive then every 1 unit increase in the prediction variable the outcome variable will increase by the beta coefficient value .
The P value for each term tests the null hypothesis that the coefficient is zero means no effect , a low P value indicate that you can reject the null hypothesis ,the P value give u an idea about which terms to keep in the regression model .R squared says how close the data are to the fitted regression line . If we get 0 % it says that model explain none of the variability of the response data around it's mean.