Friday, December 24, 2004

Christmas Eve

So it is the day before Christmas and here I am, trying to figure out how to analyze my data, again. I wish that one of my committee could tell me if I am doing this right.

Issue 1: Estimate of means and variances -
Calculated with GLM of Trait = rep entry.
  1. Output residuals
  2. Square residuals
  3. Take abs value of residuals
  4. Aggregate file by genotype
  5. Divide square residuals by counts for each genotype
  6. Perform Modified Levene's Test

Issue 2: Do the models fit assumptions of GLM?

  1. Normal residuals - no
  2. Constant variance - residuals are linear with obs value

No, but what do I do?

  1. Transform - Each variable different?
  2. Weighted least squares - What should the calc be for determining weights?
  3. Ignore it all
  4. Run away to become a beach bum in Fiji

Issue 3: How to present in only 10 minutes for two populations, 19 traits

Issue 4: Missing data

  1. When a plant yields 0 should be missing or 0?
  2. What about must pop where there are mostly missing values due to maturity?
  3. Do I include mat score as a covariate?
  4. Ignore it all?

The day is cold and there is even a chance of snow. I am going to go home to get ready for christmas. I need to finish my wife's present; I am making her a necklace for christmas. I need to assemble my daughter's bike.

Wednesday, December 22, 2004

Generation means analysis

I am trying to analyze my data from the field. If anyone has some magic SAS code for GMA I would be thrilled. I am sure doing this the slow way.


As I road to work to day, I realized that my goretex shoes had begun to leak. The rain had hit just as I left and although it faded by the time that I reached Walmart, the puddles from the road spit up from my tires and passing cars. I ride to work at a genetic lab seven miles. It is usually one of my favorite times of the day. I get to spend time thinking and today, getting wet.

My name is Brian Gardunia. I have doubts whether anyone will be reading this, but what the hey. I will be probably posting the following things:

Personal grumblings about work and school,

Questions about genetics and statistics,

Descriptions of my family life,

Itsy-Bitsy Emily Stories - Now I know that seems out of character from the rest. My daughter Emily is four, every night she begs for Itsy Bitsy Emily stories about a tiny little girl that lives with a frog in the summer and mice in the winter. But hey, I am doing this for my benefit and I hope someone out there is interested. If not, this blog will be visited by myself and myself alone.

Hello World.