st: Merge by range of values

["Jeremy A. Grey" <jagrey@umn.edu>]

Hi everyone,

I am trying to find a way to merge data sets according to a range of
values, sort of a combination of m:1 merge and inrange().

In one data set, each observation represents a subject with the
individual's value for variable X.

In another data set, each observation represents a range of values for
variable X.  The start and end values of the range are separate
variables, such as start_X and end_X.  The remaining variables contain
the values of Y and Z for all values of X within that range.

Is there a way to merge the Y and Z data from the second data set into
the first by comparing the value of X to the range specified by
start_X and end_X?

I thought of transforming the second data set in order to create new
variables, such as start_X_1, end_X_1, Y_1, Z_1, start_X_2, end_X_2,
Y_2, Z_2, etc., adding those data to each observation in the first
dataset, and using a loop and inrange() in order to compute Y and Z
for each subject, but there are about 3,000,000 different ranges of X
in the second data set, so this is impractical.

Thank you in advance for your help.

Jeremy


--
Jeremy A. Grey, MA

Doctoral Student
Division of Epidemiology and Community Health
University of Minnesota School of Public Health
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