Intro=TEXT_SLIDE("Tax Policy, Corporate Profits, and Distribution","We compare the Gini index and labor share with corporate profits relative to GNP. For each relationship, ordinary least squares provides the baseline and LP regression permits the coefficient to vary across major federal tax-policy periods.")
Guide=BULLET_SLIDE("OLS versus LP Regression","OLS estimates one average relationship across the full sample.","LP regression minimizes absolute deviations rather than squared errors.","The taxes calendar introduces period-specific coefficient adjustments.","Adjusted R-squared penalizes the LP models for their additional coefficients.")
GINI=SET_NAME(SIPOVGINIUSA,"Gini")
CPperGNP=SET_NAME(CP/GNP,"CorpProfits")
GiniData=SAME_DATE_RANGE(LIST(GINI,CPperGNP))
GiniOLSIntro=TEXT_SLIDE("Gini: OLS Baseline","The OLS model estimates one relationship between the Gini index and corporate profits relative to GNP across the entire sample.")
GiniOLS=REGRESSION(GiniData)
GiniLPIntro=TEXT_SLIDE("Gini: Tax-Period LP Regression","The LP model permits the corporate-profits coefficient to change across tax-policy periods while requiring each period-effective coefficient to remain positive.")
GiniLP=LP_REGRESSION(GiniData)
GiniLP=LP_ADD_PERIOD_EQUATION(GiniLP,"CorpProfits>0","taxes")
GiniLPModel=EX(GiniLP,model)
GiniLPCoefficients=EX(GiniLP,coefficients)
GiniLPFit=EX(GiniLP,fit)
GiniLPShadow=EX(GiniLP,shadow)
GiniChart=EX(GiniLP,actualvsfitted)
GiniChart=ADD_ANNOTATION(GiniChart,"taxes")
GiniChart=SET_TITLE(GiniChart,"Gini: Actual and Tax-Period LP Fit")
LaborShare=SET_NAME(MPU4910141,"LaborShare")
LaborData=SAME_DATE_RANGE(LIST(LaborShare,CPperGNP))
LaborOLSIntro=TEXT_SLIDE("Labor Share: OLS Baseline","The OLS model estimates one relationship between labor share and corporate profits relative to GNP across the entire sample.")
LaborOLS=REGRESSION(LaborData)
LaborLPIntro=TEXT_SLIDE("Labor Share: Tax-Period LP Regression","The LP model permits the corporate-profits coefficient to change across tax-policy periods. The broad lower bound allows negative coefficients while preventing extreme solutions.")
LaborLP=LP_REGRESSION(LaborData)
LaborLP=LP_ADD_PERIOD_EQUATION(LaborLP,"CorpProfits>-100","taxes")
LaborLPModel=EX(LaborLP,model)
LaborLPCoefficients=EX(LaborLP,coefficients)
LaborLPFit=EX(LaborLP,fit)
LaborLPShadow=EX(LaborLP,shadow)
LaborChart=EX(LaborLP,actualvsfitted)
LaborChart=ADD_ANNOTATION(LaborChart,"taxes")
LaborChart=SET_TITLE(LaborChart,"Labor Share: Actual and Tax-Period LP Fit")
Conclusion=BULLET_SLIDE("What the Comparison Shows","Adjusted R-squared indicates whether the tighter LP fit survives a penalty for the additional tax-period coefficients.","The Gini and labor-share models examine two different dimensions of income distribution.","Period adjustments identify changes in the relationship that a single OLS coefficient cannot capture.","The results describe historical associations and do not establish that individual tax acts caused the changes.")
Story=SLIDESHOW(Intro,Guide,GiniOLSIntro,GiniOLS,GiniLPIntro,GiniLPModel,GiniLPCoefficients,GiniChart,GiniLPFit,GiniLPShadow,LaborOLSIntro,LaborOLS,LaborLPIntro,LaborLPModel,LaborLPCoefficients,LaborChart,LaborLPFit,LaborLPShadow,Conclusion)