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From |
"Victor M. Zammit" <vmz@vol.net.mt> |

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

Subject |
Re: st: Re: Memory |

Date |
Thu, 13 Nov 2008 09:41:19 +0100 |

* a} The data that I have is from generating random samples of whatever size,in this case of size 31,from a normally distributed,infinitely large, population; ie local i = 1 while `i'<= 40000 { drop _all set obs 31 gen a = invnorm(uniform()) qui ttest a = 0 replace a = r(t) in 1 keep in 1 save a`i',replace local i = `i'+1 } * I use 40000 due to memory constraint.Appending the a[i]'s together gives me a variable of 40000 observations ,ie use a1,clear local i = 2 while `i'<= 40000 { append using a`i'.dta local i = `i'+1 } save ais40000,replace * b) From ais40000.dta I get the density <= 1.31, presumably to get the density of 90% , <= 1.697 to get the density of 95% etc etc,according to the official ttable, ie capture program drop density program define density use ais40000,clear count if a<= `1' di " density >=" "`1'" " = " r(N)/40000 end density 1.31 density 1.697 density 2.042 density 2.457 density 2.75 * For smaller degrees of freedom,the discrepancy is much higher.I would like to know how if it is at all possible to resolve memory constraint . ----- Original Message ----- From: "Kieran McCaul" <kamccaul@meddent.uwa.edu.au> To: <statalist@hsphsun2.harvard.edu> Sent: Thursday, November 13, 2008 5:44 AM Subject: RE: st: Re: Memory > A couple of people have responded to your previous emails and the > general thrust of these responses would suggest that no one quite > understands what it is that you are trying to do. Frankly, I don't > understand what it is that you are trying to do. > > This makes it difficult to give advice. > > So, to resolve this, why don't you explain: > > a) what data you have, and > b) what question or hypothesis you are seeking to address from these > data > > > > ______________________________________________ > Kieran McCaul MPH PhD > WA Centre for Health & Ageing (M573) > University of Western Australia > Level 6, Ainslie House > 48 Murray St > Perth 6000 > Phone: (08) 9224-2140 > Fax: (08) 9224 8009 > email: kamccaul@meddent.uwa.edu.au > http://myprofile.cos.com/mccaul > _______________________________________________ > The fact that no one understands you doesn't make you an artist. > > > -----Original Message----- > From: owner-statalist@hsphsun2.harvard.edu > [mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Victor M. > Zammit > Sent: Thursday, 13 November 2008 2:52 AM > To: statalist@hsphsun2.harvard.edu > Subject: Re: st: Re: Memory > > I have tried to take the average of resulting t-tables after appending > 40,000 ttests each time,but this practice never seem to converge to one > value ,not even after days of calculations . > I have also tried to work with the significant level only ,but this did > not > get me anywhere,either. > > > > > ----- Original Message ----- > From: "Maarten buis" <maartenbuis@yahoo.co.uk> > To: <statalist@hsphsun2.harvard.edu> > Sent: Wednesday, November 12, 2008 6:33 PM > Subject: Re: st: Re: Memory > > > > --- "Victor M. Zammit" <vmz@vol.net.mt> wrote: > > > I need to t-test an infinit number of random samples of size 30 > ,from > > > an infinite,normally distributed population. Each t-value is saved > > > and then appended together to form a database for t table.The > problem > > > is that I get constrained by memory regardless of the size of the > > > memory in my Stata. I have Version 9 .Is there a way of getting > > > around this constrained.? > > > > If you want to create a table using an infinite number of random > > samples you need an infinite amount of time and an infinite amount of > > memory, regardless of what program or computer you use. So that will > > never work. > > > > -- Maarten > > > > > > ----------------------------------------- > > Maarten L. Buis > > Department of Social Research Methodology > > Vrije Universiteit Amsterdam > > Boelelaan 1081 > > 1081 HV Amsterdam > > The Netherlands > > > > visiting address: > > Buitenveldertselaan 3 (Metropolitan), room N515 > > > > +31 20 5986715 > > > > http://home.fsw.vu.nl/m.buis/ > > ----------------------------------------- > > > > > > > > * > > * 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/ > > > > * > * 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: Memory***From:*"Nick Cox" <n.j.cox@durham.ac.uk>

**References**:**Re: st: Re: Memory***From:*"Victor M. Zammit" <vmz@vol.net.mt>

**RE: st: Re: Memory***From:*"Kieran McCaul" <kamccaul@meddent.uwa.edu.au>

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