Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, is already up and running.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

st: concentration indices and SEs (Was: Postlist for bootstrap)

From   <>
To   <>
Subject   st: concentration indices and SEs (Was: Postlist for bootstrap)
Date   Tue, 4 Jun 2013 10:12:19 +0100


Date: Mon, 3 Jun 2013 17:26:14 +0200
From: Vincenzo Carrieri <>
Subject: st: Postlist for bootstrap

Dear Statalisters,
I am trying to implement bootstrap estimations of standard errors for
concentration indexes but I get an error like: the variable "sesso"
(name of the first variable that I use in the regression) was not
found. I think that the problem is mostly on the use of postfile but I
cannot find the solution.

Here an example of what I did using just few variables.

I first using data:

use "C:\Users\User\Desktop\TEST.dta", replace

Then I Declare variable names and filename of dataset where results
will be stored

postfile test2 my ciy m01 b01 ci01 using

Then I launch my programme

capture program drop index
program define index
regress sesso eta
predict sesso
sum sesso
scalar my = r(mean)
sum eta
scalar m01=r(mean)

tempname my ciy m01 b01  ci01
sca b01 = _b[eta]
gen rank=reddito

I compute  concentration indices
  corr rank sesso        , c
     sca ciy           = 2*r(cov_12)/my
  corr rank eta        , c
     sca ci01           = 2*r(cov_12)/m01

post stak my ciy m01 b01 ci01


Up to now everything is ok.

Finally I do boostrap:

bootstrap , reps(10) : index

Here I get the error message: variable sesso not found an error
occurred when bootstrap executed index

My code  would continue:

I close the postfile

postclose test2

use "C:\Users\User\Desktop\test.dta", replace

sum my ciy m01 b01 ci01

Anyone can help me to understand what is wrong in my bootstrap

Any help is appreciated.


Not the answer to your question, but ...

... For calculation of concentration indices and bootstrapping, I
recommend the -sgini- package by Philippe Van Kerm.

Look at , which has the program
(downloadable) plus good documentation

Install the package from within Stata by typing:
    net describe sgini , from( 


Stephen P. Jenkins <>
Professor of Economic and Social Policy
Department of Social Policy 
London School of Economics and Political Science
Houghton Street, London WC2A 2AE, UK
Tel: +44(0)20 7955 6527
The Great Recession and the Distribution of Household Incomes, OUP 2013,
Changing Fortunes: Income Mobility and Poverty Dynamics in Britain, OUP
Survival Analysis Using Stata:
Downloadable papers and software:

Please access the attached hyperlink for an important electronic communications disclaimer:

*   For searches and help try:

© Copyright 1996–2015 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index