In: Statistics and Probability
| 
 Participant  | 
 Hours of Exercise  | 
 Life Satisfaction  | 
| 
 1  | 
 3  | 
 1  | 
| 
 2  | 
 14  | 
 2  | 
| 
 3  | 
 14  | 
 4  | 
| 
 4  | 
 14  | 
 4  | 
| 
 5  | 
 3  | 
 10  | 
| 
 6  | 
 5  | 
 5  | 
| 
 7  | 
 10  | 
 3  | 
| 
 8  | 
 11  | 
 4  | 
| 
 9  | 
 8  | 
 8  | 
| 
 10  | 
 7  | 
 4  | 
| 
 11  | 
 6  | 
 9  | 
| 
 12  | 
 11  | 
 5  | 
| 
 13  | 
 6  | 
 4  | 
| 
 14  | 
 11  | 
 10  | 
| 
 15  | 
 8  | 
 4  | 
| 
 16  | 
 15  | 
 7  | 
| 
 17  | 
 8  | 
 4  | 
| 
 18  | 
 8  | 
 5  | 
| 
 19  | 
 10  | 
 4  | 
| 
 20  | 
 5  | 
 4  | 
Problem statement: Based on the observed data points try to answer a set of questions.
Given: Hours of exercise per week and life satisfaction observed of twenty individuals.
Solution:
(a):Mean hours of exercise per week for all participants is
given by : summit
= 8.85 Hours.
(b): Variance and standard deviation of exercise hours is given
by : Variance=
=
13.39
standard deviation= square root(Variance)= 3.66
(c): Correlation : This provides the strength of linear relationship along with the direction (positive or negative) between weekly exercise and life satisfaction.
Correlation= Covariance ( Weekly exercise and life satisfaction)/(standard deviation(weekly exercise)*standard deviation(life satisfaction)= -0.10346. With this correlation value , we can conclude that there is no linear relationship weekly exercise hours and life satisfaction.
(d) A simple linear regression model is built using life satisfaction as target variable and weekly exercise as predictor variable.
regression equation
life satisfaction= 
1*(weekly exercise)+
0
We observe that the P-value of the regression model is 0.664, implying that weekly exercise is not a good predictor variable to compute life satisfaction.
The R2 obtained for the model is 0.01. This implies 1% variation in the life satisfaction is attributed to weekly exercise hours.
(e) : Model equation
life satisfaction= -0.07* (weekly exercise in hours)+ 5.67
Since the p-value for weekly exercise is>0.05, the variable weekly exercise is not adding any information to the regression model.