#delimit ;
clear;
set more off;
set memory 200000;
set maxvar 32000;
version 9.0;

capture: log close;
log using "c:\data\psid\eco 721\lab2.log", text replace;

/*********************************************************************************/
/* Program: lab2_long_cons_read.do -- Stata do file to read 1968-87 consumption  */
/*          and other data from the PSID and to illustrate some longitudinal     */
/*          data techniques                                                      */
/*                                                                               */
/* Authors: D. Ribar                                            March 2009       */
/*********************************************************************************/

/* Read/input data set                                                           */

use "c:\data\psid\eco 721\psid_cons_68_87.dta", clear;

/* Describe and summarize the data set for documentation purposes                */

describe;

sum;

/* Sort data by household identifier (int_id) and the observation year           */

sort int_id year;

/* Create difference variable using food needs; note difference can't be defined */
/*   until at least the second record and can't be defined for 1974              */

by int_id: generate lnfdstch = ln(tvfdstd) - ln(tvfdstd[_n-1]) if _n>1 & year!=1974; 

label var lnfdstch   "Change in log food needs";   

/* Create dummy variables corresponding to each year                             */

tabulate year, ge(yeard) nofreq;

sum;                                     

log close;

clear;

#delimit cr