Wikipedia:Reference desk/Archives/Mathematics/2011 January 24

= January 24 =

z scores on a ti 84 plus
what are some ways to find z scores on a tI 84 plus calculator?Accdude92 (talk) 16:00, 24 January 2011 (UTC)
 * Could you please give some more explanation, and Wikify wherever possible. I'm not sure I understand your question. Thanks. — Fly by Night  ( talk )  21:07, 24 January 2011 (UTC)
 * We have a redirect z score; obviously calculating it from the datum, mean, and standard deviation is trivial. I imagine the question is "How do I evaluate the normal CDF on a TI-84 Plus?", which just means evaluating the error function.  The manual for that series doesn't say it provides the error function, but you can try it (e.g.,  ); otherwise, you can use one of the numerical approximations given in the article, or perhaps the interactive "Z test" that the calculator provides is usable for this.  --Tardis (talk) 00:35, 25 January 2011 (UTC)

Looking for a math word
In mathematics, what is a word that is the opposite of a sample. It should be another word than population, because population implies living things and I am talking about events. 24.92.70.160 (talk) 17:23, 24 January 2011 (UTC)


 * It looks like you are referring to statistics. If so, population is what you want. It does not imply living things. -- k a i n a w &trade; 17:35, 24 January 2011 (UTC)

I should have been more clear. I am referring to statistics, but I need the word for a paper about humanities, and to the common person not trained in statistics population does imply living things. The context I need it for is: This action should be viewed as a sample, and not as a _____. Although most people would understand the use of sample here they would probably be confused by the use of the word population in the blank. 24.92.70.160 (talk) 17:53, 24 January 2011 (UTC)


 * Just state what it is a sample/population of: This is a sample of events, not a complete population of all events. -- k a i n a w &trade; 18:13, 24 January 2011 (UTC)


 * Sometimes "universe" is used. Bubba73 You talkin' to me? 19:39, 24 January 2011 (UTC)


 * When I hear "population", it is a "closed set". When I hear "universe", it is an "open set".  Of course, that requires defining open and closed sets.  In my field of work, a closed set is a set where each member is known - so you could count them all up if you wanted to.  An open set is a set in which members meet a description, but it is not known how many there are.  Given an item, you can tell if it is a member or not, but you don't know every possible member.  An example could be: The set of all 3-digit integers containing a 2.  The size of the population is easy to calculate.  The set of all integers with containing a 2.  The size is infinite, but identifying membership is easy.  So, the first is a population.  The second is a universe.  Of course, if you switch to a different field you will get entirely new definitions for all of this. --  k a i n a w &trade; 19:45, 24 January 2011 (UTC)


 * If you're looking for a layman's term, how about "totality"? If that's close but not quite the word you want, see if you can find the right word in a thesaurus. —Bkell (talk) 20:32, 24 January 2011 (UTC)

In Euclidean_Geometry the common notion no 5 is that the whole is greater than the part. So we may use the word whole for population and part for sample. Bo Jacoby (talk) 20:37, 26 January 2011 (UTC).