Dave Nelson wrote:

Most conductor's logs will contain more than 25 trains. Tim and I have
looked at several thousand boxcar entries from hundreds of trains. They
give a clear and unambigous body of data that shows those railroads with the
most boxcars (e.g., PRR, NYC) have their cars recorded most often and those
with the least, least often, with everybody else in between, generally
falling in line by the size of their boxcar fleet.

I am convinced by these data for the overall national behavior. But if anything, these combined data will OBSCURE local differences with particular trains. Tim O'Connor has made this point: the modeler wonders if a PARTICULAR train exhibits the overall averages. Statistically and in common sense, the answer must be NO. To some extent, that's what Mike Brock is saying.
You can't have it both ways: the bigger the sample, the less information about particular trains. That solves some problems, sure, but obscures others.

Tony Thompson Editor, Signature Press, Berkeley, CA
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