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, **statalist.org** is already up and running.

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

From |
Ozgur Ozdemir <ozdemirozgur@hotmail.com> |

To |
Stata <statalist@hsphsun2.harvard.edu> |

Subject |
RE: st: qladder |

Date |
Thu, 22 Sep 2011 11:56:52 +0000 |

Thanks Nic, you are right, in my case, residuals I think should be normally distributed and i am happy with it but when I run the ovtest, it does not reject the null hypothesis, that means, something is wrong with the transformations or interactions within the model, not sure if i really need to pass the ovtest. I did not see lots of papers reported ovtest results anyway. kind regards Ozgur ---------------------------------------- > Date: Thu, 22 Sep 2011 12:52:31 +0100 > Subject: Re: st: qladder > From: njcoxstata@gmail.com > To: statalist@hsphsun2.harvard.edu > > I don't think I can suggest a complete list for you. You need to look > at good publications in your field and talk to your > advisors/supervisors/committee about what is expected. The idea of a > link function is perhaps best covered in books on generalised linear > models which, to be frank, are from what you say likely to be a tough > read for you. > > That said, the purpose of -qladder- is to suggest transformations that > make data more nearly normal. However, it is not an assumption of > regression that data are normally distributed. Consider x = 1(1)10, y > = 2 + 3x. Here regression makes perfect sense and it is not a problem > that neither y nor x is normally distributed. > > Nick > > On Thu, Sep 22, 2011 at 12:42 PM, Ozgur Ozdemir > <ozdemirozgur@hotmail.com> wrote: > > > > > > Hi Nick, > > that is great, thanks, what kind of link functions? meanwhile, I am very new to Stata and just collected my data for my phd however still struggling with regression analysis. it seems, it will be difficult than what I expected. How can i find a complete list of activities to be done during a regression / step by step journey ? it seems, i am finding something new everyday. thanks in advance. > > > > > > > > > > > > > > > > kind regards > > Ozgur Ozdemir > > T: +44 (0) 75 0332 9865 > > E: ozdemirozgur@hotmail.com<mailto:ozdemirozgur@hotmail.com> > > Skype : ozgurozdemir2005 > > > > > > ---------------------------------------- > >> Date: Thu, 22 Sep 2011 12:38:44 +0100 > >> Subject: Re: st: qladder > >> From: njcoxstata@gmail.com > >> To: statalist@hsphsun2.harvard.edu > >> > >> It's enough that some are real zeros for the transformations concerned > >> to be invalid. That doesn't rule out using link functions that indulge > >> zeros. > >> > >> Nick > >> > >> On Thu, Sep 22, 2011 at 12:35 PM, Ozgur Ozdemir > >> <ozdemirozgur@hotmail.com> wrote: > >> > > >> > Hi Nic, > >> > It seems you are right, i have too many zeros but some of them are real zeros, and some of them are missing values. i am not sure how I can handle it. > >> > > >> > > >> > > >> > > >> >> From: njcoxstata@gmail.com > >> >> To: statalist@hsphsun2.harvard.edu > >> >> > >> >> The implication is that you have zeros in your data so that the > >> >> transformations not plotted are not computable for all values. It is > >> >> thus not clear that you are missing anything that could be useful. > >> >> > >> >> Nick > >> >> > >> >> On Thu, Sep 22, 2011 at 12:18 PM, Ozgur Ozdemir > >> >> <ozdemirozgur@hotmail.com> wrote: > >> >> > >> >> > when I use the qladder command, it does show only four graphs including cubic, square, identity and square root. but does not show i.e inverse, 1/square and some others. Is there any way that I can get others graphed? > >> >> > > > * > * 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**:**R: st: qladder***From:*"Carlo Lazzaro" <carlo.lazzaro@tin.it>

**Re: st: qladder***From:*Nick Cox <njcoxstata@gmail.com>

**References**:**st: qladder***From:*Ozgur Ozdemir <ozdemirozgur@hotmail.com>

**Re: st: qladder***From:*Nick Cox <njcoxstata@gmail.com>

**RE: st: qladder***From:*Ozgur Ozdemir <ozdemirozgur@hotmail.com>

**Re: st: qladder***From:*Nick Cox <njcoxstata@gmail.com>

**RE: st: qladder***From:*Ozgur Ozdemir <ozdemirozgur@hotmail.com>

**Re: st: qladder***From:*Nick Cox <njcoxstata@gmail.com>

- Prev by Date:
**Re: st: qladder** - Next by Date:
**Re: st: qladder** - Previous by thread:
**Re: st: qladder** - Next by thread:
**Re: st: qladder** - Index(es):