* HINT: * The program assumes that all files are stored in * C:\monographregression\computercode * change directory if code is located elsewhere * to store the figures a subfolder `figures' has to be * created clear cd C:\monographregression\computercode use "data\stata\patentdata.dta" * Delete extreme observations drop if nclaims>60 drop if ncit > 15 * Generate centered variables summarize year generate yearc = year - r(mean) summarize ncountry generate ncountryc = ncountry -r(mean) summarize nclaims generate nclaimsc = nclaims-r(mean) * Generate centered polynomials generate year2 = yearc^2 summarize year2 generate year2c=year2-r(mean) generate year3 = yearc^3 summarize year3 generate year3c=year3-r(mean) generate ncountry2 = ncountryc^2 summarize ncountry2 generate ncountry2c=ncountry2-r(mean) generate ncountry3 =ncountryc^3 summarize ncountry3 generate ncountry3c=ncountry3-r(mean) generate nclaims2 = nclaimsc^2 summarize nclaims2 generate nclaims2c=nclaims2-r(mean) generate nclaims3 =nclaimsc^3 summarize nclaims3 generate nclaims3c=nclaims3 - r(mean) * Linear effects without overdispersion glm ncit yearc ncountryc nclaimsc biopharm ustwin patus patgsgr opp , family(poisson) scale(1) estat ic * Linear effects with overdispersion, phi estimated through pearson statistic glm ncit yearc ncountryc nclaimsc biopharm ustwin patus patgsgr opp , family(poisson) scale(x2) * Save the effects of year, ncountry and nclaim matrix beta = e(b) generate f_year_lin= beta[1,1]*yearc generate f_ncountry_lin= beta[1,2]*ncountryc generate f_nclaims_lin= beta[1,3]*nclaimsc * Nonlinear effects with overdispersion, phi estimated through pearson statistic glm ncit yearc year2c year3c ncountryc ncountry2c ncountry3c nclaimsc nclaims2c nclaims3c biopharm ustwin patus patgsgr opp , family(poisson) scale(x2) estat ic * Save the effects of year, ncountry and nclaim matrix beta = e(b) generate f_year_pol=beta[1,1]*yearc + beta[1,2]*year2c + beta[1,3]*year3c generate f_ncountry_pol=beta[1,4]*ncountryc + beta[1,5]*ncountry2c + beta[1,6]*ncountry3c generate f_nclaims_pol=beta[1,7]*nclaimsc + beta[1,8]*nclaims2c + beta[1,9]*nclaims3c * Plot of the effects of year set scheme s1mono graph twoway scatter f_year_pol f_year_lin year , sort/* */ subtitle("Effects of the grant year") /* */ lwidth(medthick medthick medthick) msize(medlarge medlarge medlarge) c(l l) msymbol(i i) mcolor(black black) /* */ xlab(1980(5)1995,labsize(medium)) ylab(-1(0.25)0.75,labsize(medium)) xsize(4.5) /* */ ytitle("centered effect",size(medium)) xtitle("grant year",size(medium)) legend(off) graph export figures\effektjahr.eps, as(eps) replace * Plot of the effects of ncountry graph twoway scatter f_ncountry_pol f_ncountry_lin ncountry , sort/* */ lwidth(medthick medthick medthick) msize(medlarge medlarge medlarge) c(l l) msymbol(i i) mcolor(black black) /* */ subtitle("Effects of the number of countries",size(medium)) /* */ xlab(0(3)18,labsize(medium)) ylab(-1.25(0.25)0.5,labsize(medium)) xsize(4.5) /* */ ytitle("centered effect",size(medium)) xtitle("number of countries",size(medium)) legend(off) graph export figures\effektaland.eps, as(eps) replace * Plot of the effects of nclaims graph twoway scatter f_nclaims_pol f_nclaims_lin nclaims , sort/* */ lwidth(medthick medthick medthick) msize(medlarge medlarge medlarge) c(l l) msymbol(i i) mcolor(black black) /* */ subtitle("Effects of the number of patent claims",size(medium)) /* */ xlab(0(15)60,labsize(medium)) ylab(-0.6(0.3)0.9,labsize(medium)) xsize(4.5) /* */ ytitle("centered effect",size(medium)) xtitle("number of patent claims",size(medium)) legend(off) graph export figures\effektanspr.eps, as(eps) replace