STAT 530 Exam 2 - Due by 11:00am, Tuesday, December 9th
The exam should be turned into me, or the secretary in room 216; it should not be left in my mailbox.
For this exam you may use your notes, any text or reference book, the course web page, and any of SAS,
SPSS, or R.
You may not discuss the problems with anyone (especially your fellow students or other instructors)
except me.
You must turn in the code (or list of menu options) used to generate the output.
Each of the five questions is weighted equally.
Graduate students have an additional question (see page 3).
This exam uses two data sets:
The first data set is an excerpt of data gathered by Dunn (1928) concerning white leghorn fowl (e.g. chickens)
and can be found at:
http://www.stat.sc.edu/~habing/courses/data/fowl08.txt
The six columns in the data set are:
1 – ID – The ID number for the chicken
2 – SLength – The length of the skull
3 – SWidth – The width of the skull
4 – Femur – The length of the femur (on the leg)
5 – Tibia – The length of the tibia (on the leg)
6 – Humerus – The length of the humerus (on the wing)
7 – Ulna – The length of the ulna (on the wing)
8 – Age – The age of the chicken
All of the measurements (the lengths and widths in columns 2-7) are in mm and the age is in days. A set of
standardized measurements could be made by using:
standardize<-function(x){
(x-mean(x))/sd(x)}
sfowl<-apply(fowl[,2:7],2,standardize)
The second data set is http://www.stat.sc.edu/~habing/courses/data/orange.txt. The data set
concerns several samples of orange juice from several different countries (BEL, LSP, TME, and VME). Each of
them has had several chemical elements measured: boron (B), barium (BA), calcium (CA), potassium (K),
magnesium (MG), manganese (MN), phosphorous (P), rubidium (RB), and zinc (ZN). The first varibable is
simply an ID number.
A set of standardized measurements could be made by using:
standardize<-function(x){
(x-mean(x))/sd(x)}
sorange<-apply(orange[,3:11],2,standardize)
