/*****************************
 * Private Health            *
 * Author(s): Amonthep Chawla*
 *****************************/

/***************************************************************************************************
 * Product: Age profiles of private health expenditures (CFH)                                      *
 * Data requirements: Individual data on health consumption for different years or sources         *
 *	 and household data on health expenditures     						  		   *
 *    pvhealth02 = individual health consumption in 2002                                           *
 *    hcs = household health consumption      			                                       *
 * Methodology: Regression method with prices as a cubic in age                                    *
 **************************************************************************************************/

/* Tabulate per capita age profile for private health consumption from the SES 2002 then merge the *
 * unsmoothed age profile with the year 1996 that we want to estimate per capita health consumption*/

/* Age in square and cubic and dummy for age 0*/

gen a=age
gen asq=age^2
gen acub=age^3
gen a000=age==0

/* Create age profile for 1996 data allowing there is a systematic relationship between age in 1996 *
 * and per capita health consumption in 2002 									    */

egen b0=sum(pvhealth02), by(id)
gen b11=a*pvhealth02
egen b1=sum(b11), by(id)
gen b22=asq*pvhealth02
egen b2=sum(b22), by(id)
gen b33=acub*pvhealth02
egen b3=sum(b33), by(id)
gen a00=a000*pvhealth02
egen a0=sum(a00), by(id)

sort id
reg hcs b0 b1 b2 b3 a0  if id~=id[_n-1] [w=weight], nocons robust

gen bb0=_b[b0]
gen bb1=_b[b1]
gen bb2=_b[b2]
gen bb3=_b[b3]
gen x0=_b[a0]

/* Estimate per capita health consumption */

gen hcs96i=(bb0+bb1*a+bb2*asq+bb3*acub+x0)*pvhealth02

replace hcs96i=0 if hcs96i<0
recode hcs96i (.=0)

/* Allocating household health consumption to individuals using the perdicted share of individuals */

egen hhpvhealth96=sum(hcs96i), by(id)
gen sharepvhealth=hcs96i/hhpvhealth96
gen indhcs96=sharepvhealth*hcs

label var  indhcs96 "ind pvhealth96"

drop b0-sharepvhealth

table age [w=weight], content (mean indhcs96)

	
/* Adjust with aggregate control using the National Income Account */

gen betahcs=33.37992687
gen agpvhealth=betahcs*indhcs96


table age [w=weight], content (mean agpvhealth)