· 20.19 Xr20-19 Plot the following time series todetermine which of the trend models appears to fit better.
Period
1
2
3
4
5
TimeSeries
55
57
53
49
47
Period
6
7
8
9
10
TimeSeries
39
41
33
28
20
· 20.35 The following trend line and seasonal indexes were computedfrom 4 weeks of daily observations. Forecast the 7 values for nextweek. ŷ = 120 + 2.3t t= 1, 2, … , 28
Day
Seasonal Index
Sunday
1.5
Monday
.4
Tuesday
.5
Wednesday
.6
Thursday
.7
Friday
1.4
Saturday
1.9
17.39Refer to Exercise 17.16.Calculate the correlation between the father’s and the mother’s years ofeducation. Is there any sign of multicollinearity? Explain.
· Perform the Durbin–Watson test at the5% significance level to determine whether positive first-order autocorrelationexists when d = 1.10, n = 25, and k = 3.
· 17.42 Refer to Exercise 17.20.
o a. Calculate the correlation matrix.
o b. Are there signs of the presence ofmulticollinearity? Explain.
o c. Test the correlation between eachindependent variable and the dependent variable. Which independent variablesare linearly related to the dependent variable?
