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Build a Regression Model
-Can happiness be predicted? A researcher is investigating whether job satisfaction, income, and health could be good predictors of happiness. She selects a random sample of working adults and obtains the following information for each person. Each person is asked to rate their happiness and their job satisfaction on a scale of 1 to 10 . Each person is asked their annual income. Finally, each person's overall physical health is evaluated by a doctor and rated on a scale of 1 to 20 . The results are shown in the table.
(a) Construct the correlation matrix. Is there any reason to be concerned with collinearity?
(b) Find the least squares regression equation , where is job satisfaction, is income, is health, and is the response variable "happiness".
(c) Test versus : at least one of the at the level of significance.
(d) Test the hypotheses versus versus , and versus at the level of significance.
Should any of the explanatory variables be removed from the model? If so, which one? Why?
(e) Determine the least squares regression equation with the explanatory variable identified in part (d) removed.
(f) Are both slope coefficients significantly different from zero? If not, remove the appropriate explanatory variable and compute the new least squares regression equation.
(g) How does the -value for your final regression equation compare with the -value for the original equation in part (b)? What does this imply?
Predictive Analysis
The use of data, statistical algorithms, and machine learning techniques to identify the likelihood of future outcomes based on historical data.
Machine Learning
A discipline combining science, statistics, and computer coding to make predictions based on patterns discovered in data.
Sales Territories
The customer groups or geographic districts to which an individual salesperson or a sales teams sells.
Workload
The amount of work assigned to or expected from a person within a given time period.
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