1. A persistent problem in research on AIDS is the lack of a reliable measure of the stage of illness in relationship to
Posted: Wed May 11, 2022 9:10 am
1. A persistent problem in research on AIDS is the lack of a reliable measure of the stage of illness in relationship to the time the person becomes infected with the virus. A pilot study of this measure has been completed. A measure of immunologic status (X) to the AIDS virus is determined for some selected patients. The length of time in months (Y) from exposure is also recorded. The results of this survey are as follows. 6 7 13 Immunologic status (X) 4 5 12 Time from exposure (Y) 5 6 14 7 9 16 (a) Fit a simple linear regression to the data to investigate the relationship between the immunologic status and the length of time from exposure. [6] (b) Interpret the estimated value of the slope coefficient in the context of this study. [4] (c) Use the model fitted above to predict the length of time from exposure for a patient with immunologic status equal to 8. [4] (d) Calculate and interpret the coefficient of determination for this model. [5] (e) Calculate the mean square error for the fitted model [4]