st: Observations in Sequence analysis

[Sarah Park <sarahjwpark@gmail.com>]

I am studying sequence of portfolios of firms, but some firms die and
others are established after my first observation (so some firms have
observation 1-100, but others from 20-70, for example). But, I have
the order variable for those firms starting at 1 to avoid the problem
of gaps (I didn't think treating non-existing observations as missing
data made any sense). However, when I run the cluster analysis based
on the dissimilarity matrix afterwards, I have Stata categorizing some
of the sequence with same elements (ex. 333, 333333, 333333333) into
the same cluster, some into different clusters when they are clearly
the same sequence. I tried with single, wards, average, and other
measures but the result is the same.

First, is this the right way of writing the time variable?
Does anyone have any idea how to fix this problem?
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