February 19, 1947.

liirector,
Bureau of the Census,
Washing on, D.C.

The occasion-1 occurrence of families showing unusuesl trust
of boys or of girbb is a fact of everyday experience, amu hus even
been exploited to = cert in extent in references to Eadie C:.ntor
and other entertainers. There do not, however, seem to exist
analyses of such occurrences, directed at determining whether shth
occurrences can be completely succounted for on the basis of a random
distribution of the sexes in a given family, at any rate for U.S.
populations. It would be a matter of szvocstional interest to
myself to be acouninted with such wn analysis, or, lacking that to
enuuire as to the availability of data from which to mke one. The
dat» th:t would be required would be tabulitions of the sex aistribu-
tions in families of varying sizes, designated,if possible, by the
tot.1 number of birbhks Licking the latter, « texbul.ation on the biusis
of survivors of, say, the fifth year woult be sotisfuctpry.

I should be very much obliged for a) the results of any such
analyses tht may have been performed ih your bureuwu, or lucking this,
b) either references to the appropriate information, ang if possible,
the official publications containing same.

Yours sincerely,

Joshua Lederberg.