Date: Thu, 19 Aug 1999 12:37:53 0700
ReplyTo: glaser@pacificscience.com
Sender: "SPSSX(r) Discussion" <SPSSXL@LISTSERV.UGA.EDU>
From: Dale Glaser <glaser@PACIFICSCIENCE.COM>
Subject: Re: SPSS: ttest: two independent sample
InReplyTo: <19990819190220.98186.qmail@hotmail.com>
ContentType: text/plain; charset="iso88591"
Assuming you mean n = 100 per group, the answer, in my opinion, is yes; even
though I have seen some intro. texts divide hypothesis testing for two
groups as follows: (1) if n is small (e.g., n < 30) and the population
standard deviation is unknown then use the t distribution; (2) if n is large
and the population standard deviation is known then use z distribution;
however, a cursory glance at the research journals will find many examples
of ttests being employed when n is well over 30 per group; further as df
increases for the tdistribution, it approximates the zdistribution (i.e.,
critical value for df > 120 = 1.96, when alpha = .05 for twotailed test);
however, I will be interested if other researchers differ in their
opinions...............dale glaser
Original Message
From: SPSSX(r) Discussion [mailto:SPSSXL@LISTSERV.UGA.EDU] On Behalf Of
Shail Dobson
Sent: Thursday, August 19, 1999 12:02 PM
To: SPSSXL@LISTSERV.UGA.EDU
Subject: SPSS: ttest: two independent sample
Can independent ttest for means of two independent samples be performed for
sample size over 100? If not, is there any other equivalent test available?
Thank you very much,
Shail
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
