For the 18-hole courses in file golfers . dat , plot the weekend 18-hole greens fee vs . the hacktee yardage . Estimate the regression parameters s for predicting weekend greens fees from backtee , ardage . 's there a strong relationship between the two variables ? Use regression estimation to estimate the weekend 18 hole greens fee with its standard error. Use the data in file golfers .at for this problem Estimate the mean weekday greens fee to play ) holes , for courses with a golf professional available. Now estimate the mean wee"day greens fee to play 9 holes , for ourses without a golf professional 8 he data set agers .dat also contains information on the number of farms in 198/ for the SKS of n - 300 counties from the population of the N = 3078 counties in the United States (see Example 2.5 ). In 1987 , the United States had a total of 2,087.75y farins. Plot the data . D Use ratio estimation to estimate the total number of acres devoted to farming in '992 , using the number of farms in 1987 as the auxiliary variable Repeat (b ); using regression estimation P Which method gives the most precision : ratio estimation with auxiliary variable acre 87, ratio estimation with auxiliary variable farms87 , or regression estimation with auxiliary variable fam-87 ! why ? 9 Using the data set agers .dat , estimate the total number of acres devoted to farming for each of two domains : (a) counties with fewer than 600 farms , and (b) counties with 600 or more farms . Give standard errors for your estimates 10 The data set cherry .dat , from Hand et al. (1994 ), contains measurements of diameter (inches ), height (feet ), and timber volume (cubic feet ) for a sample of 31 black cherry trees . Diameter and height of trees are easily measured , but volume is more difficult to measure a Plot volume vs. diameter for the 31 trees b Suppose that these trees are an SRS from a forest of N = 2907 trees and that the sum of the diameters for all trees in the forest is f = 1,835 inches . Use ratio estimation to estimate the total volume for all trees in the forest . wive a 95 % CI. Use regression estimation to estimate the total volume for all trees in the forest Give a 95% CI. The data file counties .dat contains information on land area , population , number of physicians , unemployment , and a number of other quantities for an SRS of 100 of the 3141 counties in the United States (U.S. Census Bureau , 1994 ). The total land area for the United States is 3,535,278 square miles ; 1993 population was estimated to be 255,077,53 . Draw a histogram of the number of physicians for the 100 counties b Estimate the total number of physicians i in the United States , along with its stan - dard error, using Ny