st: clustering in bootstrap

[Marcella Nicolini <archivio.marcella@gmail.com>]

Hello, I try to do a cluster in a bootstrap, but I get the following error:

"repeated time values within panel
the most likely cause for this error is misspecifying the cluster(),
idcluster(), or group() option
r(451);"

Hower, if I tsset my data as:

tsset panel_id booking_day
       panel variable:  panel_id (strongly balanced)
        time variable:  booking_day, 1 to 70, but with gaps
                delta:  1 unit

and I have no duplicates:

. duplicates list panel_id booking_day

Duplicates in terms of panel_id booking_day

(0 observations are duplicates)

How come that there are repeated time values with cluster(panel_id)??
How can I detect the problem in my data?
Thank you
Marcella
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/