I'm currently trying to make a random stratified sampling schedule and cannot figure it out. Here is a sample of the data:
Obs Date Month S_Regions
1 Sat, Jan 8, 2011 1 3
2 Sat, Jan 29, 2011 1 7
3 Tue, Jan 18, 2011 1 3
4 Thu, Jan 6, 2011 1 3
5 Thu, Jan 20, 2011 1 8
6 Sat, Jan 1, 2011 1 2
7 Tue, Jan 25, 2011 1 3
8 Thu, Jan 13, 2011 1 5
9 Sat, Jan 22, 2011 1 1
10 Tue, Jan 4, 2011 1 6
11 Tue, Jan 11, 2011 1 6
12 Thu, Jan 27, 2011 1 4
13 Sat, Jan 15, 2011 1 1
14 Tue, Feb 22, 2011 2 6
Obs is the observation number, date is the planned date to sample (randomly ordered by date, but ordered by month), month is the planned month to sample, and S_Regions is a random number from 1 to 6. In this case the number is just a random number from 1 to 6 with no constraints on how it is chosen. What I need to do is pick a random number from 1 to 6 without replacement until all numbers have been assigned to a date, then repeat that until a number for S_regions is chosen for each date in a month. Then start the process over with the next month. I don't have any sample code yet because I'm still trying to figure out how to start this. If you have any ideas please let me know. Thanks in advance.