st: Flaggin Changes in Data

[Beatrice Benavidez <beatricestata1711@gmail.com>]

Hi everyone,

I have hotel occupancy data of individuals who change rooms in the
hotel in the following format:

Booking ID            Date           Room
17                        1/1/2013      3
17                        1/1/2013      4
17                        2/1/2013      5
17                        2/1/2013      6
27                        1/1/2013      10
27                        1/1/2013      11
27                        2/1/2013      12
37                        1/1/2013      10
37                        2/1/2013      11
37                        2/1/2013      12

I would like to flag the bookingid rooms that changed with
'Flag_rmchange' variable:

Booking ID            Date           Room               Flag_rmchange
17                        1/1/2013      3
17                        1/1/2013      4
17                        2/1/2013      5                      1
17                        2/1/2013      6                      1
27                        1/1/2013      10
27                        1/1/2013      11
27                        2/1/2013      12                    1
37                        1/1/2013      10
37                        2/1/2013      11                    1
37                        2/1/2013      12

What happened here is that I flagged bookingid rooms that were changed
from the day before. I make the flags always on the day after, see
here the flags are on 2/1. Problem is I don't know which room they
changed from the day before to the next but it shouldn't matter as I
just need to flag that did change rooms.

I would like to find a way to automatically flag the bookingid rooms
that were changed like the above, where the room they change from is
different to the room they change to, the next day.

With booking Id 17, there were two different rooms on 1/1 and two
different rooms on 2/1 so the should be two flags on 2/1. But with
booking id 27, person stayed in two rooms on 1/1 but one room on 2/1
so the flag is on 2/1 for room 12. However, with booking id 37, person
stayed in 1 room on 1/1 but two rooms on 2/1 so the flag should be
assigned to one room 2/1 as person only changed room once. I assigned
it to room 11. However, it doesn't matter if i had assigned it to
either room 11 or room 12 as long as there is one flag.

So maybe, a script can be developed where there is the same number of
rooms from one day to the next with completely different room numbers,
which means they were room changes so should be flagged.

Any suggestions would be very helpful!

Kind regards,


Beatrice
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