Panel data analysis for brand choice

[M A Ahmad]

Hi, I got a question regarding panel data to run a conditional logistic regression. I have already run the conditional logistic regression but i want to confirm whether i did it correctly or not because i'm getting errors for sum commands which i really need to do for a complete analysis ( for instance defining time variable to create lags) it says that "repeated time values" in panel. Could you please help me with this because i need to include lagged variables to capture dynamic effects of price and promotion and dependent variable? I have done my research on Google but couldn't find the solution because I didn't see any data set related to the one i got (panel + categorical outcome). Therefore, i would be grateful if any one could help me through!

I have a data on consumer choices for 10 purchase occasions; say i = 1......1360, t= 1.....10 and j= 1....4 (Individuals, choice occasions and alternatives). Since it's a panel data with a categorical dependent variable, therefore for conditional logistic I created a long form structure like (1 individual * 4 choices available) plus each individual was observed for 10 different occasions so (1*4*10) 40 rows related to each individual where four rows represent one choice occasion.
Thank You!

Note: (kindly, have a look on data set i attached or you can see a screen shot for explanation) Cracker clogit.xlsx
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Last edited by M A Ahmad; Today, 03:22.