Logistic regression is a statistical method for analyzing a dataset in which there are one or more independent variables that determine an outcome. The outcome is measured with a dichotomous variable (in which there are only two possible outcomes). It is used to predict a binary outcome (1 / 0, Yes / No, True / False) given a set of independent variables.
For example:
Suppose that we are interested in the factors that influence whether a political candidate wins an election. The outcome (response) variable is binary (0/1); win or lose.
The predictor variables of interest are the amount of money spent on the campaign, the amount of time spent campaigning negatively and whether or not the candidate is an incumbent.
The best way to learn and develop skills in applying statistical techniques is by doing. To this end, practice exercise is intended to aid you in applying the techniques of Logistic Regression.
Action Items
A principal investigator interested in predicting commitment to healthy lifestyle of recovering heart patients has recruited you as a research assistant to help with running data analysis. The commitment of patients to healthy lifestyle is coded as (0 =No, 1 = Yes). The study has one indicator variable: minority status (0 =No, 1 = Yes). In addition, educational level measured in years in school (EDUC) and the M and G Stress Test (STRESS) scored on a 1 to 5 scale, with higher scores indicating greater levels of stress were included to assess if these variables could reliably predict commitment to healthy lifestyle. You are provided with the following data attached please include sources
Based on the data provided, run a binary logistic regression analysis and answer the following questions:
- What can we tell from the overall/omnibus test? What in the results tell us if the predictors are statistically significant?
- What part of the output and accompanying can help us assess variance explained by the model? Are these tests consistent?
- Which part of the results/output tell us whether variable(s) provide a unique contribution to the prediction? What can you say about the contributions of each variable?
- What are the odds that a minority member will be committed to healthy lifestyle as compared to a non-minority member?
- What are the odds of being committed to healthy lifestyle for each increase on the stress level?
- Write one to two paragraphs of how you will report this results in finding sec