Selection effects in "normal" populations
To predict effects of selection it is helpful to investigate what happens in the standardized normal case.
A very simple EXCEL sheet was prepared for genetic variance after selection.
The two .exe programs offered from this menu are helpful for this purpose. Download them first and run them from your own computer, it is not recommended and usually not even possible to run them from this website! You can download them direct from the directory by removing the file name but keeping the path in your browser or clicking here.
The program SELEINT2.EXE calculates selection intensity for values derived from a normal distribution. Selection intensities are useful for predicting genetic gain when the j top ranking out of n are selected. The program can generate normal order statistics ("rankits") on file (the expected values of the j:th highest ranking value out of n), these can be seen as "selection intensity" (used in breeding value prediction) for an individual selection. For low n the programs uses a table in the file SELEINT.TAB, so it is needed to download that in the same directory. The program produces output files. The program was written by Dag Lindgren in 1990.
Some results from the program and more information about what it does is available in:
Lindgren, D. & Bondesson, L. 1987. Calculation of selection intensity and rankits. SLU, Dept of Forest Genetics and Plant Physiology. Arbetsrapport 23. ISSN 0280-7988.
Selection intensity in general is described by Lindgren D & Nilsson J-E (1985), Calculations concerning selection intensity. SLU, Dept of Forest Genetics and Plant Physiology. Departmental report 4.
The program SELENOR3.EXE calculates optimal contributions (linear deployment, actually) and characteristics of that, when values for genotypes are distributed as a normal distribution. It can be used to dimension the number of ramets from each clone in clonal seed orchards and clonal mixtures. It was written by Dag Lindgren in 1990. It may be shared freely.
Some output from SELENOR.EXE and more information about what it does is available in:
Lindgren, D. 1991. Optimal utilization of genetic resources. Forest Tree Improvement nr 23. s. 49-67.
Lindgren, D. & Bondesson, L. 1990. Optimal utilization: Normal approximation and the case of an upper bound on the utilization. SLU, Inst. f. skoglig genetik och växtfysiologi. Arbetsrapport 39. ISSN 0280-7988.
last edit DL 09-03-09