July 11, 1994

Quercus is the name for a collection of 
programs written by Ruth G. Shaw and Frank H. Shaw for the 
analysis of quantitive genetic data by maximum likelihood.  At 
present, the package is made up of four programs (nf3.p, nf6.p, 
pcrf1.p, and fend.p) and accompanying documentation (doc),
example input, and example output files.  The 
programs nf3.p and nf6.p perform maximum likelihood analysis of 
data from a single population.  nf3.p carries out the analysis 
using a model involving three types of variance components (by 
default, additive, dominance, environmental), whereas nf6.p 
estimates up to six components of (co)variance estimable from 
diallel data.  pcrf1.p carries out comparion of genetic variance-
covariance matrices between two (genetically unrelated) populations.  
Please see the documentation for more extensive information on 
these programs.

Earlier versions of these programs (qg3.p, qg6.p, and pcr2.p)
differ principally in one respect from the current versions.  This 
is in the handling of feasibility constraints.  A few minor
errors have also been corrected.  Generally, if feasibility
constraints are not used, the new programs should give the same
answers as the old ones did.  Please let us know if this is
not the case!

We are currently testing programs 1) that permit analysis of 
general pedigrees and 2) that test the null hypothesis that a 
genetic correlation equals 1.  We anticipate adding the former of these
to the Quercus package in the near future. If you obtain any programs 
from this set, please let us know by sending an e-mail message to 
shaw@superb.ecology.umn.edu.

This work has been sponsored by NIH (GM09664-02) and NSF (BSR-8817756,
BSR-8905808, and DIR-9112842).  We owe an incalculable debt to Joe Felsenstein,
who served as the original mentor for this project.  We have relied very 
heavily on the path-breaking work of Robin Thompson and Karin Meyer.  The 
programs have been made much more convenient to use as a result of the 
constructive suggestions of a number of intrepid and indefatigable users. 
Chief among these is Bruce Riska.  We gratefully acknowledge the involvement
of all these contributors.

Ruth Shaw and Frank Shaw