Re: E as a % of a standard deviation

2001-11-25 Thread Barry Edwards
Algebraically, E = [z(a/2) / SQRT(n)] x SD, so it must be that the margin of error (maximum error as you called it) is a multiple of the population standard deviation. Keep in mind what these values represent. E is the margin of error of the estimate of mu, the population mean. SD is the

Re: Standard Deviation!

2001-11-12 Thread Rich Ulrich
On Sun, 11 Nov 2001 01:30:27 +1100, "David Muir" <[EMAIL PROTECTED]> wrote: > Presently the Gaming Industry of Australia is attempting to define various > new 'definitions of Standard Deviation'...in a concept to define infield > metrics for the analysis of ma

Re: Standard Deviation!

2001-11-12 Thread Dennis Roberts
i think you are asking the wrong question ... because, as far as i know ... there is only really one standard deviation concept ... square root of the variance (average of squared deviations around the mean in a set of data) ... perhaps what you are really interested in is HOW should

Standard Deviation!

2001-11-10 Thread David Muir
Presently the Gaming Industry of Australia is attempting to define various new 'definitions of Standard Deviation'...in a concept to define infield metrics for the analysis of machines in terms which imply whether a machine is being operated with respect to its defined percentage

Re: Mean and Standard Deviation

2001-10-16 Thread Glen Barnett
Edward Dreyer wrote: > > A colleague of mine - not a subscriber to this helpful list - asked me if > it is possible for the standard deviation > to be larger than the mean. If so, under what conditions? Of course - for example, if you analyse mean-corrected data... It can even

Re: Mean and Standard Deviation

2001-10-14 Thread Alan McLean
possible for the SD to be larger than the mean, but the distribution will then be not symmetric. Alan Edward Dreyer wrote: > > A colleague of mine - not a subscriber to this helpful list - asked me if > it is possible for the standard deviation > to be larger than the mean. If so

Re: Mean and Standard Deviation

2001-10-14 Thread Jay Warner
Well, yes. the mean and standard deviation are not 'linked' for data with a Normal distribution. Dale Glaser asked: Well, what about the standard normal distribution: N(0,1)? The mean is 0, the standard deviation, 1. If you add the restriction that the data not be less than 0, a

RE: Mean and Standard Deviation

2001-10-12 Thread Dale Glaser
Title: RE: Mean and Standard Deviation Well, what about the standard normal distribution: N(0,1)?   Dale N. Glaser, Ph.D. Pacific Science & Engineering Group 6310 Greenwich Drive; Suite 200 San Diego, CA 92122 Phone: (858) 535-1661 Fax: (858) 535-1665 http://www.pac

Re: Mean and Standard Deviation

2001-10-12 Thread Ken Beath
In article <[EMAIL PROTECTED]>, Edward Dreyer <[EMAIL PROTECTED]> wrote: > A colleague of mine - not a subscriber to this helpful list - asked me if > it is possible for the standard deviation > to be larger than the mean. If so, under what conditions? > E

Re: Mean and Standard Deviation

2001-10-12 Thread dennis roberts
At 04:32 PM 10/12/01 -0500, you wrote: >A colleague of mine - not a subscriber to this helpful list - asked me if >it is possible for the standard deviation >to be larger than the mean. If so, under what conditions? what about z scores??? mean = 0 and sd = 1 >At first blush I do

RE: Mean and Standard Deviation

2001-10-12 Thread Simon, Steve, PhD
Title: RE: Mean and Standard Deviation Edward Dreyer writes: >A colleague of mine - not a subscriber to this helpful >list - asked me if it is possible for the standard deviation >to be larger than the mean.  If so, under what conditions? > >At first blush I do not think so

Mean and Standard Deviation

2001-10-12 Thread Edward Dreyer
A colleague of mine - not a subscriber to this helpful list - asked me if it is possible for the standard deviation to be larger than the mean. If so, under what conditions? At first blush I do not think so - but then I believe I have seen some research results in which standard

Re: E as a % of a standard deviation

2001-10-02 Thread Magenta
1.96 * (sigma / sqrt n) > > > > now, what n might it take to produce some e? we can rearrange the formula > ... > > > > sqrt n = (1.96 * sigma) / e > > > > but, we don't want sqrt n ... we WANT n! > > > > n = ((

Re: E as a % of a standard deviation

2001-09-30 Thread Rich Ulrich
On Sun, 30 Sep 2001 00:34:40 GMT, "John Jackson" <[EMAIL PROTECTED]> wrote: > Here is my solution using figures which are self-explanatory: > > Sample Size Determination > > pi = 50% central area 0.99 > confid level= 99%

Re: E as a % of a standard deviation

2001-09-30 Thread John Jackson
Donald, I totally agree w/your point about the stratification of the sample. My facts were set up merely for simplicity's sake notwithstanding their clear artificiality. The only instances of multiple samples I have seen are in textbooks to prove the CLT; that w/increasing numbers of sample mean

Re: E as a % of a standard deviation

2001-09-29 Thread Donald Burrill
On Sun, 30 Sep 2001, John Jackson wrote: > Here is my solution using figures which are self-explanatory: > > Sample Size Determination > > pi = 50% central area 0.99 > confid level= 99% 2 tail area 0.5 > sa

Re: E as a % of a standard deviation

2001-09-29 Thread John Jackson
en my clarification, I would > welcome your insights. > > > "Donald Burrill" <[EMAIL PROTECTED]> wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > On Fri, 28 Sep 2001, John Jackson wrote in part: > > > > > My formu

Re: E as a % of a standard deviation

2001-09-29 Thread John Jackson
terval formula shown > > below for ascertaining the maximum error. > E = Z(a/2) x SD/SQRT N > > The issue is you want to solve for N, but you have no standard > > deviation value. > Oh, but you do. In the problem you formulated, unless I > misunderstood egregiously, you

Re: E as a % of a standard deviation

2001-09-29 Thread Donald Burrill
On Fri, 28 Sep 2001, John Jackson wrote in part: > My formula is a rearrangement of the confidence interval formula shown > below for ascertaining the maximum error. E = Z(a/2) x SD/SQRT N > The issue is you want to solve for N, but you have no standard > dev

Re: E as a % of a standard deviation

2001-09-28 Thread John Jackson
/ sqrt n) > > now, what n might it take to produce some e? we can rearrange the formula ... > > sqrt n = (1.96 * sigma) / e > > but, we don't want sqrt n ... we WANT n! > > n = ((1.96 * sigma)/ e) ^2 > > so, what if we wanted to be within 3 points o

Re: E as a % of a standard deviation

2001-09-28 Thread John Jackson
Really sorry. My formula is a rearrangement of the confidence interval formula shown below for ascertaining the maximum error. E = Z(a/2) x SD/SQRT N The issue is you want to solve for N, but you have no standard deviation value. The formula then translates into n = (Z(a/2)*SD)/E)^2Note

Re: E as a % of a standard deviation

2001-09-28 Thread Paul Bellamy
gt; > now, what n might it take to produce some e? we can rearrange the formula ... > > sqrt n = (1.96 * sigma) / e > > but, we don't want sqrt n ... we WANT n! > > n = ((1.96 * sigma)/ e) ^2 > > so, what if we wanted to be within 3 po

Re: E as a % of a standard deviation

2001-09-28 Thread Dennis Roberts
? we can rearrange the formula ... sqrt n = (1.96 * sigma) / e but, we don't want sqrt n ... we WANT n! n = ((1.96 * sigma)/ e) ^2 so, what if we wanted to be within 3 points of mu with our sample mean the population standard deviation or sigma we

Re: E as a % of a standard deviation

2001-09-28 Thread Randy Poe
John Jackson wrote: > the forumla I was using was n = (Z?/e)^2 and attempting to express .05 as a > fraction of a std dev. I think you posted that before, and it's still getting garbled. We see a Z followed by a question mark, and have no idea what was actually intended. - Randy ===

Re: E as a % of a standard deviation

2001-09-27 Thread John Jackson
OTECTED]">news:MGns7.49824$[EMAIL PROTECTED]... > > re: the formula: > > > > n = (Z?/e)2 > > This formula hasn't come over at all well. Please note that newsgroups > work in ascii. What's it supposed to look like? What's it a formula fo

Re: E as a % of a standard deviation

2001-09-26 Thread Glen Barnett
supposed to look like? What's it a formula for? > could you express E as a % of a standard deviation . What's E? The above formula doesn't have a (capital) E. What is Z? n? e? > In other words does a .02 error translate into .02/1 standard deviations, > assuming you are

Re: E as a % of a standard deviation

2001-09-26 Thread Dennis Roberts
At 04:49 PM 9/26/01 +, John Jackson wrote: >re: the formula: > > n = (Z?/e)2 > > >could you express E as a % of a standard deviation . > >In other words does a .02 error translate into .02/1 standard deviations, >assuming you are dealing w/a normal dist

Re: error estimate as fraction of standard deviation

2001-09-26 Thread John Jackson
Thanks for the formula, but I was really interested in knowing what % of a standard deviation corresponds to E. In other words does a .02 error translate into .02/1 standard deviations? "Graeme Byrne" <[EMAIL PROTECTED]> wrote in message 9orn26$m80$[EMAIL PROTECTED]"&g

E as a % of a standard deviation

2001-09-26 Thread John Jackson
re: the formula: n = (Z?/e)2 could you express E as a % of a standard deviation . In other words does a .02 error translate into .02/1 standard deviations, assuming you are dealing w/a normal distribution

Re: error estimate as fraction of standard deviation

2001-09-25 Thread Graeme Byrne
This sounds like homework but I will . Anyway assume the normal approximation to the binomial can be used (is this reasonable?) then the formula for estimating sample sizes based on a given confidence level and a given maximum error is n = z*Sqrt(p*(1-p))/e where z = the z-scores associated wit

error estimate as fraction of standard deviation

2001-09-25 Thread @Home
If you have a confidence level of 90% and an error estimate of 4% and don't know the std deviation, is there a way to express the error estimate as a fraction of a std deviation? = Instructions for joining and leaving this list a

Re: standard deviation from frequency table

2001-01-10 Thread Paolo Covelli
Referring your example: variance = 2_nd moment - (1_st moment), that is: 2_nd moment = 0^2 * 0.2 + 1^2 * 0.3 + 2^2 * 0.2 + 3^2 * 0.2 + 4^2 * 0.1 = 4.5 1_st moment = 0 * 0.2 + 1 * 0.3 + 2 * 0.2 + 3 * 0.2 + 4 * 0.1 = 1.7 then variance = 4.5 - (1.7)^2 = 1.61 then standard deviation = sqrt(1.61

Re: standard deviation from frequency table

2001-01-08 Thread Robert J. MacG. Dawson
Chris Chiu wrote: > > Dear friends: > > Does anyone know / remember how to obtain the standard deviation of a set > of numbers given only a frequency table? > > e.g., > xf(x) > 00.2 > 10.3 > 20.2 > 30.2 > 40.1 (0

standard deviation from frequency table

2001-01-06 Thread Bob Hayden
QUESTIONS Dear friends: Does anyone know / remember how to obtain the standard deviation of a set of numbers given only a frequency table? e.g., xf(x) 00.2 10.3 20.2 30.2 40.1 Many thanks. Chris ONE POSSIBLE ANSWER: Here is a worked solution. I used the Windows

Re: standard deviation from frequency table

2001-01-06 Thread Konrad Halupka
Chris Chiu wrote: > > Dear friends: > > Does anyone know / remember how to obtain the standard deviation of a set > of numbers given only a frequency table? > > e.g., > xf(x) > 00.2 > 10.3 > 20.2 > 30.2 > 40.1 > > Many t

Re: standard deviation from frequency table

2001-01-06 Thread dennis roberts
ng as the X values are fixed ... and the p values ... then you could do it that way ... of course, without the X values .. you are lost At 09:35 AM 1/6/01 -0500, Chris Chiu wrote: >Dear friends: > >Does anyone know / remember how to obtain the standard deviation of a set >of num

standard deviation from frequency table

2001-01-06 Thread Chris Chiu
Dear friends: Does anyone know / remember how to obtain the standard deviation of a set of numbers given only a frequency table? e.g., xf(x) 00.2 10.3 20.2 30.2 40.1 Many thanks. Chris = Instructions

Re: Standard deviation/confidence interval help.

2000-11-23 Thread Li0N_iN_0iL
Mark Solberg <[EMAIL PROTECTED]> wrote: >I've had some statistics coursework, probably just enough to be dangerous. > >Here's my problem. By the way this is an actual problem, not theoretical. >I need to analyze the hold percentage on certain table games in the casino I >work at. I should think

RE: Standard deviation/confidence interval help.

2000-11-23 Thread Simon, Steve, PhD
exist, i.e. theft, bad game protection, etc.. > >The data I have is for each day, I have the calculated hold percentage for >each of the individual table games. There are multiple table games of each >type, for example there are 7 blackjack tables. > >Q: I want to calculate the st

Standard deviation/confidence interval help.

2000-11-13 Thread Mark Solberg
multiple table games of each type, for example there are 7 blackjack tables. Q: I want to calculate the standard deviation and confidence interval for blackjack by week. Do I add the total win and total drop for the entire week and establish a weekly hold percentage and use multiple weeks to

Re: What is standard deviation exactly?

2000-05-22 Thread Duncan Murdoch
On Mon, 22 May 2000 13:24:25 +1000, "Glen Barnett" <[EMAIL PROTECTED]> wrote: >I assume you're talking about sample standard deviations, >not population standard deviations (though interpretation >of what it represents is similar). > > ... > >Note tha

Re: What is standard deviation exactly?

2000-05-22 Thread Paul Gardner
Glen Barnett wrote: > > In article <[EMAIL PROTECTED]>, > Neil <[EMAIL PROTECTED]> wrote: > >I was wondering what the standard deviation means exactly? > > > >I've seen the equation, etc., but I don't really understand > >what st dev is

Re: What is standard deviation exactly?

2000-05-21 Thread Glen Barnett
In article <[EMAIL PROTECTED]>, Neil <[EMAIL PROTECTED]> wrote: >I was wondering what the standard deviation means exactly? > >I've seen the equation, etc., but I don't really understand >what st dev is and what it is for. I'm going to take a differ

Re: What is standard deviation exactly?

2000-05-21 Thread Alan McLean
There are a couple of (practical) features of the standard deviation that are worth noting. First, as a *descriptor* of the variation in a distribution, it is generally not very good. I mean this is the sense that if you want to visualise the amount of variation in a distribution the SD is only

Re: What is standard deviation exactly?

2000-05-21 Thread Herman Rubin
In article <[EMAIL PROTECTED]>, Neil <[EMAIL PROTECTED]> wrote: >I was wondering what the standard deviation means exactly? >I've seen the equation, etc., but I don't really understand >what st dev is and what it is for. >I am not a statistician as you can te

Re: Programs for Standard Deviation

2000-03-24 Thread D. Gall
In article <mtAB4.8354$[EMAIL PROTECTED]>, [EMAIL PROTECTED] says... > >My daughter has asked me if there are any tools / software programs that can >resolve standard deviations, while Excel can determine a standard deviation >of the Population, what formula is used for the

Re: Programs for Standard Deviation

2000-03-21 Thread dennis roberts
well, to be honest with you ... i have never heard of these terms before ... i am wondering if your daughter has the term standard deviation mixed up with perhaps ... percentile rank? At 01:43 AM 03/21/2000 +, Robert Meyer wrote: >My daughter has asked me if there are any tools / softw

Re: Programs for Standard Deviation

2000-03-21 Thread Donald F. Burrill
On Tue, 21 Mar 2000, Robert Meyer wrote: > My daughter has asked me if there are any tools / software programs > that can resolve standard deviations; while Excel can determine a > standard deviation of the Population, what formula is used for the > (A) 5th Standard Deviatio

Re[2]: Programs for Standard Deviation

2000-03-21 Thread Kolenikov, Stanislav
Robert A. Meyer asked what is / which software calculates >(A) 5th Standard Deviation >(B) 10th Standard Deviation >(C) 25th Standard Deviation >(D) 40'th Standard Deviation and T.S. Lim answered, > I think you're looking for PERCENTILES. I would say that there ac

Re: Programs for Standard Deviation

2000-03-20 Thread T.S. Lim
In article <mtAB4.8354$[EMAIL PROTECTED]>, [EMAIL PROTECTED] says... > >My daughter has asked me if there are any tools / software programs that can >resolve standard deviations, while Excel can determine a standard deviation >of the Population, what formula is used for the T

Programs for Standard Deviation

2000-03-20 Thread Robert Meyer
My daughter has asked me if there are any tools / software programs that can resolve standard deviations, while Excel can determine a standard deviation of the Population, what formula is used for the (A) 5th Standard Deviation (B) 10th Standard Deviation (C) 25th Standard Deviation (D) 40&#x

Re: pooled standard deviation

2000-02-23 Thread John W. Kulig
n) from an omnibus anova, and take the square root of it. Just curious: What are you planning to do with a pooled standard deviation? Anna Geyer wrote: > How do I calculate pooled standard deviation? I have > study with group of exercisers following forward over > time. I wan

pooled standard deviation

2000-02-23 Thread Anna Geyer
How do I calculate pooled standard deviation? I have study with group of exercisers following forward over time. I want look at weight by category of calorie intake. I look at standard deviation for weight for each calorie group but want one overall standard deviation. Is this valid? Thank