I am interested in examining the effect of government funds on the start-up patenting activity. I observe a set of startups and their patenting activity over time. My dataset covers around 20 years, and the startups contained in the dataset are launched in different years. In the data, I observe patenting activities of start ups to decay over time i.e. if they generate 10 patents in their first year, then they generate 8 in the next year, 5 after 2 years later and so on. Given this information:
My first question is: If they get the funds on their second years, most likely I would be underestimating the effect of government funds due to natural decay of number of patents over time. How to deal with this?
My second question is: How to deal with multiple treatments i.e. if start up receives more than one government fund?
My third question is: Since year fixed effects basically demeans the average patents for the particular year and start-ups are more likely to come up with more patents in their first couple of years, fixed effects are likely to de-maen more if there are more start ups entering in a given year. How could I deal with this?
Example data is here:
I am currently using following command:
My first question is: If they get the funds on their second years, most likely I would be underestimating the effect of government funds due to natural decay of number of patents over time. How to deal with this?
My second question is: How to deal with multiple treatments i.e. if start up receives more than one government fund?
My third question is: Since year fixed effects basically demeans the average patents for the particular year and start-ups are more likely to come up with more patents in their first couple of years, fixed effects are likely to de-maen more if there are more start ups entering in a given year. How could I deal with this?
Example data is here:
Code:
* Example generated by -dataex-. To install: ssc install dataex clear input double company_id float(postfund n_patents year) 57593 0 5 1996 57593 0 0 1997 57593 0 0 1998 57593 0 0 1999 57593 0 0 2000 57593 0 1 2001 57593 0 0 2002 85598 0 2 1988 85598 0 0 1989 85598 0 1 1990 85598 0 0 1991 85598 0 0 1992 85598 0 1 1993 85598 0 0 1994 85598 0 0 1995 85598 0 1 1996 85598 0 0 1997 85598 0 0 1998 85598 0 0 1999 85598 0 0 2000 85598 0 0 2001 85598 0 0 2002 164211 0 3 1994 164211 0 0 1995 164211 0 0 1996 164211 0 0 1997 164211 0 0 1998 164211 0 0 1999 164211 0 0 2000 164211 0 0 2001 164211 0 0 2002 219942 0 4 1991 219942 0 8 1992 219942 0 0 1993 219942 0 1 1994 219942 0 0 1995 219942 0 1 1996 219942 0 0 1997 219942 0 0 1998 219942 0 0 1999 219942 0 0 2000 219942 0 0 2001 219942 0 0 2002 259008 0 2 1984 259008 0 15 1985 259008 0 15 1986 259008 0 1 1987 259008 0 1 1988 259008 0 1 1989 259008 0 0 1990 259008 0 1 1991 259008 0 1 1992 259008 0 1 1993 259008 0 0 1994 259008 0 1 1995 259008 0 0 1996 259008 0 1 1997 259008 0 0 1998 259008 0 0 1999 259008 0 0 2000 259008 0 0 2001 259008 0 0 2002 259613 0 17 1983 259613 0 1 1984 259613 0 1 1985 259613 1 1 1986 259613 2 2 1987 259613 2 1 1988 259613 2 1 1989 259613 2 0 1990 259613 2 1 1991 259613 3 2 1992 259613 3 0 1993 259613 3 0 1994 259613 3 0 1995 259613 4 0 1996 259613 4 0 1997 259613 4 0 1998 259613 4 1 1999 259613 4 0 2000 259613 4 1 2001 259613 4 0 2002 264590 0 6 1994 264590 0 0 1995 264590 0 0 1996 264590 0 0 1997 264590 0 0 1998 264590 0 0 1999 264590 0 0 2000 264590 0 0 2001 264590 0 0 2002 266164 0 1 1989 266164 0 0 1990 266164 0 0 1991 266164 0 0 1992 266164 0 0 1993 266164 0 0 1994 266164 0 0 1995 266164 0 0 1996 266164 0 0 1997 end
Code:
xtreg log_patents postfund i.year,fe vce(cluster company_id)
