Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.

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

From |
David Kantor <kantor.d@att.net> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: RE: RE: carryforward |

Date |
Mon, 23 Jan 2012 14:01:28 -0500 |

I never expected this to invoke such a reaction.

by person_id (date): carryforward salary marital_status, replace

I hope this is helpful. --David At 12:58 PM 1/23/2012, Nick Cox wrote:

If this method is one of imputing missing values that in practicewill be varying by a constant that was the last observed value, thenas Tony implies it clearly can be problematic.But the method of replacing missing values by previous non-missingvalues is one I often use with small datasets entered by hand. Whenthe observations come in blocks, I only need to type in values forthe first identifier in each block, and then -replace- appropriately.Sometimes datasets arrive like that too. Only the first value in ablock of some blocked variable is explicit, so you have to fill in(or fill out) implied similar values.Nick n.j.cox@durham.ac.uk Lachenbruch, PeterThis method has been seriously questioned and gives very pooranswers generally. A true p-value may be reported anywhere from0.01 to0.15 when it should be 0.05. I strongly urge it not be used.________________________________________From: owner-statalist@hsphsun2.harvard.edu[owner-statalist@hsphsun2.harvard.edu] On Behalf Of David Kantor[kantor.d@att.net]Once again, thanks to Kit Baum, a new version of -carryforward- is available on SSC. This upgrade adds the -if- and -in- qualifiers. Actually, the upgrade was written a long time ago, but never got uploaded until now. Sorry, if that was my fault. -carryforward- carries values from one observation to the next, filling in missing values. -ssc install carryforward-

* * 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/

**References**:**st: carryforward***From:*David Kantor <kantor.d@att.net>

**st: RE: carryforward***From:*"Lachenbruch, Peter" <Peter.Lachenbruch@oregonstate.edu>

**st: RE: RE: carryforward***From:*Nick Cox <n.j.cox@durham.ac.uk>

- Prev by Date:
**Re: st: RE: RE: carryforward** - Next by Date:
**st: xtmelogit cross-classified groups** - Previous by thread:
**Re: st: RE: RE: carryforward** - Next by thread:
**st: carryforward** - Index(es):