Dear All,
I am looking for your kind help in the following STATA problem.
I am working on student record data with school years in the range of 2003 to 2014. Students had different universtiy entering years. The number of years they studied at the university varies from one to four or more, and the number of courses they took each year varies as well.
I would want to create a new sequencing variable to identify whether it is a student's first year, second year and so on at the univerity. In the data sample below, the variabe "cpyear" stands for school year, and crscod for course code.
The new variable will help me to identify if a student entered university in 2005 and took 10 courses in the 2005 school year , a value of 1 is attached to the variable all the way down. In the 2006 school year, the variable will show a value of 2 for all the courses he took, and so on.
If a student entered university in 2007 and took 8 courses, then the variable will attach a value of 1 to that student for all the courses taken, and value of 2 in the 2008 school year, and so on. There are missing values for school years.
I have experimented commands to create a new sequencing variable by looping over the student id and the school year variables, but not successful:
by id cpyear, sort: gen syear_sq = cond(_N==1,0,_n)
bys id cpyear: gen syear_sq=_n
bys id cpyear: gen synew=1 if _n==1
I also tried to generate new id by using the -egen- and concat command: egen idcpyear=concat(id cpyearString), and then created a new school year sequence.
Many thanks for your help.
Thang
+++++
Below is a sample of my student record data.
id cpyear crscod
15894 2005 ENG1122
15894 2005 ESP1991
15894 2005 PSY1102
15894 2005 PHI1102
15894 2005 MUS1301
15894 2005 ENG1100
15894 2005 ENG2320
15894 2005 ESP1992
15894 2005 PHI1101
15894 2005 ENG1123
15894 2006 CRM2307
15894 2006 CRM1300
15894 2006 CRM2310
15894 2006 CRM2306
15894 2006 CRM2305
15894 2006 CRM1301
15894 2006 FLS1511
15894 2006 CMN1148
15894 2006 FLS1512
15894 2007 ENG2400
15894 2007 CRM2308
15894 2007 CRM3334
15894 2007 CRM3316
15894 2007 CRM3303
15894 2007 CRM3301
15894 2007 CRM2303
15894 2007 CRM2301
15894 2007 CRM2300
15894 2007 CRM2310
15894 2007 ENG3362
15894 2008 ANT1101
15894 2008 ENG3134
15894 2008 ENG3339
15894 2008 ENG3318
15894 2008 ENG2450
15894 2008 SOC3137
15894 2008 CRM2303
15894 2008 ENG3133
15894 2008 ENG2450
15894 2008 CRM3301
15894 2008 CRM3315
15894 2008 CRM2300
15894 2008 ENG3340
15894 2009 ENG3362
15894 2009 ENG4120
15894 2009 ENG3318
15894 2009 ENG3341
15894 2009 ENG4151
15895 2005 CMN1120
15895 2005 PHI1101
15895 2005 CLA2101
15895 2005 PHI1102
15895 2005 ENG1121
15895 2005 SOC1102
15895 2005 PHI1370
15895 2005 ENG1122
15895 2005 PSY1102
id cpyear crscod
32805 2003 CRM2307
32805 2003 SOC2309
32805 2003 SRS1110
32805 2003 SOC3141
32805 2003 PSY3101
32805 2003 ANT3131
32805 2003 POL1501
32805 2003 SRS2191
32805 2003 CRM3306
32805 2003 SOC3131
32805 PSY1101
32805 CRM2305
32805 CRM1300
32805 SOC2106
32805 CRM1301
I am looking for your kind help in the following STATA problem.
I am working on student record data with school years in the range of 2003 to 2014. Students had different universtiy entering years. The number of years they studied at the university varies from one to four or more, and the number of courses they took each year varies as well.
I would want to create a new sequencing variable to identify whether it is a student's first year, second year and so on at the univerity. In the data sample below, the variabe "cpyear" stands for school year, and crscod for course code.
The new variable will help me to identify if a student entered university in 2005 and took 10 courses in the 2005 school year , a value of 1 is attached to the variable all the way down. In the 2006 school year, the variable will show a value of 2 for all the courses he took, and so on.
If a student entered university in 2007 and took 8 courses, then the variable will attach a value of 1 to that student for all the courses taken, and value of 2 in the 2008 school year, and so on. There are missing values for school years.
I have experimented commands to create a new sequencing variable by looping over the student id and the school year variables, but not successful:
by id cpyear, sort: gen syear_sq = cond(_N==1,0,_n)
bys id cpyear: gen syear_sq=_n
bys id cpyear: gen synew=1 if _n==1
I also tried to generate new id by using the -egen- and concat command: egen idcpyear=concat(id cpyearString), and then created a new school year sequence.
Many thanks for your help.
Thang
+++++
Below is a sample of my student record data.
id cpyear crscod
15894 2005 ENG1122
15894 2005 ESP1991
15894 2005 PSY1102
15894 2005 PHI1102
15894 2005 MUS1301
15894 2005 ENG1100
15894 2005 ENG2320
15894 2005 ESP1992
15894 2005 PHI1101
15894 2005 ENG1123
15894 2006 CRM2307
15894 2006 CRM1300
15894 2006 CRM2310
15894 2006 CRM2306
15894 2006 CRM2305
15894 2006 CRM1301
15894 2006 FLS1511
15894 2006 CMN1148
15894 2006 FLS1512
15894 2007 ENG2400
15894 2007 CRM2308
15894 2007 CRM3334
15894 2007 CRM3316
15894 2007 CRM3303
15894 2007 CRM3301
15894 2007 CRM2303
15894 2007 CRM2301
15894 2007 CRM2300
15894 2007 CRM2310
15894 2007 ENG3362
15894 2008 ANT1101
15894 2008 ENG3134
15894 2008 ENG3339
15894 2008 ENG3318
15894 2008 ENG2450
15894 2008 SOC3137
15894 2008 CRM2303
15894 2008 ENG3133
15894 2008 ENG2450
15894 2008 CRM3301
15894 2008 CRM3315
15894 2008 CRM2300
15894 2008 ENG3340
15894 2009 ENG3362
15894 2009 ENG4120
15894 2009 ENG3318
15894 2009 ENG3341
15894 2009 ENG4151
15895 2005 CMN1120
15895 2005 PHI1101
15895 2005 CLA2101
15895 2005 PHI1102
15895 2005 ENG1121
15895 2005 SOC1102
15895 2005 PHI1370
15895 2005 ENG1122
15895 2005 PSY1102
id cpyear crscod
32805 2003 CRM2307
32805 2003 SOC2309
32805 2003 SRS1110
32805 2003 SOC3141
32805 2003 PSY3101
32805 2003 ANT3131
32805 2003 POL1501
32805 2003 SRS2191
32805 2003 CRM3306
32805 2003 SOC3131
32805 PSY1101
32805 CRM2305
32805 CRM1300
32805 SOC2106
32805 CRM1301