A sample of 25 blue-collar employees at the production plant was taken. Each and every employee was asked to determine his own job satisfaction (x) on scale from 1 to 10. Additionally, the numbers of days absent (y) from work throughout the last year were found for these employees. The sample regression line yi=11.6-1.2x was determined by least squares for these data.
Also found were:
Sample mean = 6
Sum of (x-x mean) 2=130
SSE= 80.6
a) Test at the 1% significance level against appropriate one-sided alternative null hypothesis that job satisfaction has no linear effect upon absenteeism.
b) A specific employee has job satisfaction level 4. Determine a 90% interval for the number of days this employee would be absent from work in year.