Question

A university is concerned about the presence of grade inflation, which is defined as an increase in the average GPA of the institution's students over time without a comparable increase in academic standards. To investigate this phenomenon, the average GPA for the student body was recorded over the past 11 years, as shown in the table to the right. Construct a 90% confidence interval for the regression slope.	Year	GPA		Year	GPA
	1	3.08		7	3.08
	2	2.88		8	2.98
	3	2.98		9	3.19
	4	2.87		10	3.16
	5	2.99		11	3.15
	6	3.03

Construct a 90% confidence interval for the slope.

LCL=

UCL=

Answer 1

from above LCL =0.0072

UCL =0.0366