Notice: On March 31, it was **announced** that Statalist is moving from an email list to a **forum**. The old list will shut down at the end of May, and its replacement, **statalist.org** is already up and running.

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

From |
John Antonakis <john.antonakis@unil.ch> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: Re: comparing regression discontinuity treatment effects for different subsamples |

Date |
Tue, 12 Oct 2010 23:20:07 +0200 |

Hi Austin:

group =1 if pretest of person i is less than or equal to mean of pretest group =0 if pretest of person i is greater than pretest We provide the treatment to group 1, and we estimate: y = b0 + b1*(pretest - mean pretest) + b2*group + e

Best, J. __________________________________________ Prof. John Antonakis, Associate Dean Faculty of Business and Economics (HEC) Department of Organizational Behavior University of Lausanne Internef #618 CH-1015 Lausanne-Dorigny Switzerland Tel ++41 (0)21 692-3438 Fax ++41 (0)21 692-3305 Home page: http://www.hec.unil.ch/people/jantonakis __________________________________________ On 12.10.2010 22:10, Austin Nichols wrote:

In that case, I strongly disagree with your advice--you are constraining the slope of pretest to be the same on both sides of the discontinuity, and not using any concept of a bandwidth around the cutoff; local linear regression is the standard approach, not linear regression. Further, if you mean to subtract the mean of the assignment variable when you say "pretest is mean-centered" then the coefficient on group does not measure the jump in outcomes at the cutoff unless the cutoff happens to be right at the mean of pretest. On Tue, Oct 12, 2010 at 8:50 AM, John Antonakis<john.antonakis@unil.ch> wrote:Hi Austin: Using the "classical" RDD design, "group" is the treatment indicator; pretest is the "cutoff" measure for assignment to group. Best, On 12.10.2010 03:34, Austin Nichols wrote:John -- I don't understand your advice here at all--is group supposed to be a treatment indicator? Is pretest an assignment variable or a control variable? Prashant -- One can of course write a wrapper -program- containing several estimators and -bootstrap- the whole thing, which then allows testing across estimators--the -rd- package on SSC is no exception to that general rule, but make sure you set the bandwidth exogenously if you are using local linear regression as -rd- does. Also -findit ivqte- for one approach to quantile TE, and note that RD can be seen as a version of IV; see refs cited in -help rd-. On Mon, Oct 11, 2010 at 3:04 AM, John Antonakis<john.antonakis@unil.ch> wrote:Hi: You could use -suest-. For example, suppose you have the following basic specification (where pretest is mean-centered, to set the intercept to the cut-off value): y = b0 + b1*pretest + b2*group + e Estimate the model for each group, e.g., reg y pretest group if boys==1 est store boys reg y pretest group if boys==0 est store girls suest boys girls Now you can do cross-equation tests, e.g., test [boys_mean]group = [girls_mean]group Hope this helps. John.* * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

* * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

**Follow-Ups**:**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*Austin Nichols <austinnichols@gmail.com>

**References**:**st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*Prashant <presearchwork@gmail.com>

**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*John Antonakis <john.antonakis@unil.ch>

**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*Austin Nichols <austinnichols@gmail.com>

**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*John Antonakis <john.antonakis@unil.ch>

**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples***From:*Austin Nichols <austinnichols@gmail.com>

- Prev by Date:
**st: RE: gpscore for propensity score of 4 observed groups** - Next by Date:
**Re: st: RE: date formatting** - Previous by thread:
**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples** - Next by thread:
**Re: st: Re: comparing regression discontinuity treatment effects for different subsamples** - Index(es):