Question

4. Table C2-4 shows the total number of customer complaints (relating to late delivery, damaged packaging, or product quality/defects) reported and the total number of customer accounts serviced for the past four years.
a. Show the scatter diagram and compute the covariance for the two sets of values (treating the data as a population and compute and interpret the correlation coefficient to see if there is a positive or negative correlation between the variables.IN EXCEL PLEASE.

Table C2-4: Customer Complaints and Customer Accounts Served
Year	Total Customer Complaints	Total Accounts Served
2013	98	130
2014	86	164
2015	62	193
2016	103	143

Answer 1

Scatter Plot

Covariance is computed using Excel function COVARIANCE.P(Complaints data, Accounts Served data)  
Covariance = -357.125
Correlation Coefficient is computed using Excel function CORREL(Complaints data, Accounts Served data)  
Correlation Coefficient =   -0.947036378
Interpretation :  
The absolute value of the correlation coefficient is closer to 1 implying the correlation is very strong  
The correlation coefficient is negative implying the correlation is negative  
Thus there is a very strong negative correlation between the variables.