Listed below are the log body weights and log brain weights ofthe primates species in the data set ”mammals”. Find the equationof the least squares line with y = log brain weight and x = logbody weight. Do it by hand, by constructing a table like the one inExample 9.1. Then do it with your calculator as efficiently aspossible. Finally, use the lm function in R to do it by creating alinear model object ”primates.lm”. The model formula is”log(brain)?log(body)”. You can select the primates and put them ina new data frame by first listing the primate species names:

> primatenames=c(”Owl monkey”, ”Patas monkey”, ”Gorilla”,etc.)

and then

> primates=mammals[primatenames, ]

Your ”data” argument in calling lm would be ”data=primates”, asin

> primates.lm=lm(log(brain)?log(body),data=primates)

Alternatively, you can just use ”mammals[primatenames, ]” as thedata argument in lm, that is,

> primates.lm=lm(log(brain)?log(body),data=mammals[primatenames,])

log body             log brain

Owl monkey                     -0.7339692         2.740840

Patas monkey                  2.3025851          4.744932

Gorilla                                 5.3327188          6.006353

Human                               4.1271344          7.185387

Rhesus monkey                              1.9169226          5.187386

Chimpanzee                                     3.9543159          6.086775

Baboon                                               2.3561259          5.190175

Verbet                                                1.4327007          4.060443

Galago                                                 -1.6094379        1.609438

Slow loris                                           0.3364722          2.525729