We assume that our wages will increase as we gain experience andbecome more valuable to our employers. Wages also increase becauseof inflation. By examining a sample of employees at a given pointin time, we can look at part of the picture. How does length ofservice (LOS) relate to wages? The data here (data96.dat) is theLOS in months and wages for 60 women who work in Indiana banks.Wages are yearly total income divided by the number of weeksworked. We have multiplied wages by a constant for reasons ofconfidentiality.

(a) Plot wages versus LOS. Consider the relationship and whetheror not linear regression might be appropriate. (Do this on paper.Your instructor may ask you to turn in this graph.)

(b) Find the least-squares line. Summarize the significance testfor the slope. What do you conclude?

Wages =	+  LOS
t =
P =

(c) State carefully what the slope tells you about the relationshipbetween wages and length of service.


(d) Give a 95% confidence interval for the slope.
(  ,  )

worker wages  los   size1    61.372 54   Large2    42.7536 33   Small3    45.7298 57   Small4    59.9747 63   Small5    66.9318 190   Large6    47.0695 112   Small7    49.306 41   Large8    41.0451 49   Large9    55.3925 29   Large10   51.586 51   Small11   48.8118 34   Large12   47.6549 49   Small13   51.9155 58   Small14   49.4336 71   Large15   49.0055 59   Large16   67.1645 54   Large17   41.0187 146   Large18   66.6989 64   Small19   37.3414 57   Large20   41.1314 44   Large21   68.2611 54   Large22   49.2968 146   Small23   41.31  71   Large24   51.4378 131   Small25   39.8553 92   Large26   46.3618 137   Small27   49.451 31   Small28   41.2582 85   Large29   56.6397 46   Large30   43.6494 98   Large31   43.9767 125   Small32   44.4695 87   Large33   45.9359 95   Large34   42.7246 100   Small35   45.1822 111   Large36   67.6785 126   Large37   47.3643 115   Large38   44.4952 41   Small39   41.0943 58   Large40   43.894 133   Small41   49.3584 49   Small42   48.877 86   Small43   55.4153 37   Large44   52.4565 25   Small45   79.1435 85   Large46   47.3674 121   Small47   37.8021 81   Large48   38.0888 31   Large49   40.4484 146   Small50   45.4833 15   Large51   53.525 38   Large52   52.6821 102   Large53   42.9239 18   Large54   40.1348 168   Small55   75.9808 72   Small56   37.1931 24   Large57   48.2541 36   Small58   49.557 44   Large59   79.727 28   Small60   53.8476 56   Large