Animal ecologists wish to track the health of bear populations in the wild. By obtaining physical measurements of bears, researchers can gauge the effects of changes taking place in and around bear habitat (e.g., nearby housing and business development, recreational activities, introduction of non-native plant and animal species, severe storms, harsh winters, etc.). Researchers have studied bears by anesthetizing them in order to obtain vital measurements, such as age, gender, length, and width. A bear's weight is another important variable that is quite difficult to obtain in the wild because most bears are heavy and difficult to lift. The scientific problem is to develop a method for predicting the weight of a bear, given other more easily obtained measurements. A good method might alleviate the need to weigh bears in the wild and greatly simplify the data collection process. In one detailed study, researchers were able to obtain weight measurements along with several other variables for each of 54 bears. The data set contains 54 rows and 9 columns. There is one row for each bear that was anesthetized and measured carefully using a tape measure and scale. There is one column for each variable in the data set. The variables (from left to right) are age: age in months length: length of body in inches sex: 1=male 2=female weight: weight in pounds chest: chest circumference in inches headlth: length of head in inches headwth: width of head in inches month: month of capture (1=January, 2=February, etc.) neck: neck circumference in inches