A survey conducted by a research team was set to investigate how the education level, tenure in current

employment, professional certification and age, are related to annual income. A sample of 20 employees

is selected and the data is provided in the accompanying Excel file.

a) Find the regression model for this example.

b) Find Se and Interpret.

c) Find R2 and state what this value tells you about the model.

d) Test the validity of the model with 95% confidence.

e) Test with 95% confidence whether Professional Certification is related to Annual Income.

f) Test with 95% confidence whether Education is related to Annual Income.

g) Test with 95% confidence whether Length of Tenure is related to Annual Income.

h) Test with 95% confidence whether Age is related to Annual Income.

i) Provide a scatter plot of the data.

j) Are there any outliers to consider?

k) Does multicollinearity exist?

THE EXCEL FILE PASTED BELOW.

Education (No. of years)	Length of tenure in current employment (No. of years)	Age (No. of years)	Professional Training	Annual income ($)
17	15	40	Professional Training	124,000
12	5	32	No Professional Training	30,000
20	18	44	Professional Training	193,000
14	6	42	Professional Training	88,000
12	2	19	No Professional Training	27,000
14	8	28	No Professional Training	43,000
12	11	43	Professional Training	96,000
18	13	41	Professional Training	110,000
16	6	36	Professional Training	88,000
11	5	33	No Professional Training	36,000
16	6	36	Professional Training	81,000
12	5	29	No Professional Training	38,000
16	17	45	Professional Training	140,000
13	1	42	No Professional Training	11,000
11	2	18	No Professional Training	21,000
20	10	40	Professional Training	151,000
19	11	35	Professional Training	124,000
16	5	38	No Professional Training	48,000
12	2	19	No Professional Training	26,000
10	13	44	Professional Training	124,000