st: data management question

[David Airey <david.airey@vanderbilt.edu>]

Dear List,

I have two data sets that I want to put together to analyze with a 
nested model.

The first data set looks like:

group        var
1            2
1            3
1            2
2            5
2            4
3            3
3            4
3            5
3            5

Thus there will be roughly balanced data by group. Group in this case 
is really different inbred strains of mice. Each row above is an 
animal. Thus there are 3 animals for group 1, 2 for group 2, and 4 for 
group 3. Var will be a continuously distributed dependent variable.

The other data set looks like:

marker  group_1  group_2  group_3
1       aa       aa       bb
2       aa       aa       bb
3       aa       bb       bb

In this data set, each row is a genetic marker. The second to fourth 
columns are genetic information for each marker for each group.

I want the get the data together such that it looks like:

group    var   marker_1    marker_2    marker_3
1        2     aa          aa          aa
1        3     aa          aa          aa
1        2     aa          aa          aa
2        5     aa          aa          bb
2        4     aa          aa          bb
3        3     bb          bb          bb
3        4     bb          bb          bb
3        5     bb          bb          bb
3        5     bb          bb          bb

Notice that each animal in a group has the same genetic information for 
any particular marker, but var may differ between animals. The basic 
model to analyze these data by marker will nest animal in marker to 
predict var.

My problem is how to write a program that is smart enough to properly 
repeat the genetic information by group in bringing the two files 
together. The number of animals per group may change from file to file 
and the number of markers may change also, but each group will have 
genetic information at each marker (no missing genetic information).

Thanks much for any help or example code on similar problems.

Sincerely,

Dave

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