ST 555 -- Summer 2013

  Homework #2 -- Due TUESDAY, 04 June 2013

  In the files scfall05.dat and scfall06.dat in the 'sum13b' directory are 
  measurements of resin flows from pine tree (compiled by Kate Whitley 
  Blinka) as part of an investigation of the resistence of loblolly pines
  to the southern pine beetle.  The data on each record takes the form:
      block   clone   treenumber   resinns   resinew 
  The trees planted in blocks (locations) in a large plantation in South 
  Carolina with each clone occuring once in each block.  Two measurements 
  of resin flow were taken on each tree, with one boring in the North-South 
  direction (resinns), and one in the East-West direction (resinew).  Two 
  clones were used as checks, 'CC4' and '756'; these should be deleted from 
  your analysis.

  1) Compute the mean and variance for each block for both the N-S and
  E-W bores. (class or by) 

  2) Construct bar charts for the distribution of resin flows for both
  N-S and E-W bores.  (Two charts)

  3) Compute the variances for the differences ( (E-W) - (N-S) ) for 
  each block (think class or by block).  If fatigue has an effect, then 
  we may see the variances increasing according to the order of sampling.

  *) If the last digit of your student id number is odd use scfall05.dat;
  if even, use scfall06.dat.
                             
       FOR ALL EXERCISES: Hand in
        (1)  Your program
            * With as many comments as you have toes! *
        (2)  Your output
        (3)  The answers to the questions asked.