Question

11.6.4 An article in the Journal of Sound and Vibration (Vol. 151, 1991, pp. 383-394) described a study investigating the relationship between noise exposure and hypertension. The following data are representative of those reported in the article. Y| 1 0 1 2 5 1 4 6 2 3 5 4 6 845-1916 x 60 63 65 70 70 70 80 90 80 80 85 89 90 90 90 90 94 100 100 100 Assume y = blood pressure rise and x = sound pressure level. Round your answers to 3 decimal places. Find a 95.00% confidence interval on each of the following: (a) Bo (b) B1. (c) Mean blood pressure rise when the sound pressure level is 86 decibels. (d) Find a 95.00% prediction interval on blood pressure rise when the sound pressure level is 86 decibels.

Answer 1

code in R is done for the analysis

code with output is attached herewith

y <- c(1, 0, 1, 2, 5, 1, 4, 6, 2, 3, 5, 4, 6, 8, 4, 5, 7, 9, 7, 6) X <- c(60, 63, 65, 70, 70, 70, 80, 90, 80, 80, 85, 89, 90, 99, 90, 90, 94, 100, 100, 100) model <- Im(y-x) #a) beta model$coefficients[1] ## (Intercept) ## -10.13154 #b) beta 1 model$coefficients [2] ## 0.1742939 newdata <- data.frame(x = 86) #c) meanbp <- predict(model, newdata = newdata, se.fit = T, interval - "confidence") #Lower meanbp$fit[2] ## [1] 4.218198 #upper meanbp$fit[3] ## [1] 5.497283 #d) predbp <- predict(model, newdata = newdata, se.fit = T, interval - "prediction") #Lower predbp$fit[2] ## [1] 2.015905 #upper predbp$fit[3] ## [1] 7.699576