t vs. z

1999-12-15 Thread Bob Hayden
- Forwarded message from Olsen, Chris - It would seem to me that more than this most can be said. If my reading of the central limit theorem is up to snuff, I should be able to use the "Z test with s" without an underlying assumption of the normality of the parent population, required

Re: adjusting marks

1999-12-21 Thread Bob Hayden
- Forwarded message from David A. Heiser - I don't agree with Demming. Life is essentially a matter of diversity, and being able to find one's own "niche". The process of ranking is inherent in life whenever there is stress on a population. Going to college is indeed "stress". - End

Re: Anti-Aristotelian?

2000-01-01 Thread Bob Hayden
- Forwarded message from Herman Rubin - Galileo questioned the conclusions which had been obtained from Aristotle's philosophizing Even the use of "algebraic" notation escaped the people who would have done much more if they had it. It was a half millennium after Archimedes and

Re: Distribution generator for simulator in C++

2000-01-11 Thread Bob Hayden
Dave Nulton wrote: Quite frankly Robert the details are proprietary. I suppose I could have been more descriptive, but I don't see what the shape of my distribution have to do with what it represents Well, our expertise is also proprietary!-) _ | | Robert W. Hayden

probability of a boy

2000-01-22 Thread Bob Hayden
- Forwarded message from Wolfgang Rolke - From [EMAIL PROTECTED] Sat Jan 22 10:47:51 2000 From: Wolfgang Rolke [EMAIL PROTECTED] Hi, I am looking for information (journal article, web site ect.) on the difference in birth rates for boys and girls. Specifically I would like to find

Re: this list

2000-03-01 Thread Bob Hayden
experiencing inner peace. Bob Hayden wrote: There was talk of making this into a subscriber-only list. Perhaps it is time to do that and to limit membership to the civil. _ | | Robert W. Hayden | | Department of Mathematics / | Plymouth

Re: over and above

2000-03-23 Thread Bob Hayden
- Forwarded message from Herman Rubin - It is the concepts which are the most important part, and concepts need little, if any, practice. One should give a variety of exercises, and the student should do as much as is necessary. - End of forwarded message from Herman Rubin -

Re: Calculator policy

2000-03-25 Thread Bob Hayden
"Brian E. Smith" wrote: I am trying to formulate a calculator policy in a department that currently allows any calculator except "those capable of storing text". Brian said nothing to suggest he authored or supports these policies so please don't be too hard on him if you (as I) disagree

Xbar and Square Root symbols in HTML

2000-03-27 Thread Bob Hayden
- Forwarded message from Kristen Lanum - Hello! We are trying to render the symbols for Xbar and square root in a statistics manual, which will primarily be used by staff using Internet Explorer 5. Is there any way to render these symbols for the web other than making them into graphics?

Re: Data Mining blooper and Related Subjects (fwd)

2000-04-28 Thread Bob Hayden
- Forwarded message from Debasmit Mohanty - I think, now is the time when we have to decide "Do we accept DATA MINING as a part of statistics or do we keep neglecting this field as before". I am sure there would be few statistics students like me who feel that Data Mining is very much

Re: Data Mining blooper and Related Subjects

2000-04-29 Thread Bob Hayden
- Forwarded message from Frank E Harrell Jr - I'd like to make a somewhat related point. There are many educational tools that I've found have a great effect on non-statisticians. One if these is to take one of their datasets, randomly permute the column of Y-values, go through their

what is s.d.?

2000-05-22 Thread Bob Hayden
The standard deviation of a single batch of numbers is a typical value for the residuals (deviations from the mean). If you divide by n, it is the RMS mean of the residuals. You can check your calculation of the s.d. by comparing it to the residuals. The mean is the measure of center that

WHY is heteroscedasticity bad? (fwd)

2000-05-30 Thread Bob Hayden
This may not fully answer all your questions, but the various formulas for inference for regression have a place where you plug in THE variance of the points around the regression model, i.e., they treat this as a constant. If it is not a constant, the results of the formulas will not be

correlation coefficient for a curve fit equation

2000-06-01 Thread Bob Hayden
- Forwarded message from Mike Stephenson - I curve fit some data to the equation 1/y=a+bx using a set of x, y data. I used the 1/y form in the curve fit because I could use a linear least squares approach. I treated 1/y as "Y" for the curve fit exercise. If I were to use it as y=f(x),

Summer courses

2000-06-10 Thread Bob Hayden
- Forwarded message from Sandra - I'm a PhD student (2nd year). Do you know if there are any summer courses in statistics? - End of forwarded message from Sandra - I took some at Iowa State many years ago. _ | |Robert W. Hayden | |

cubic footnotes

2000-07-01 Thread Bob Hayden
Re the chicks data posted by Don Burrill... A reference is Snedecor and Cochran, Statistical Methods (7th ed.), Iowa State University Press, Ames, IA, 1980, pp.394-406, which gives an extensive analysis, including fitting an exponential and orthogonal polynomials. There is more on orthogonality

literature on convenience sampling

2000-07-05 Thread Bob Hayden
- Forwarded message from Susanne Muigg - now I'm about to finish my thesis, but still looking for some literature about the advantages and disadvantages of a (student) convenience sample, which I had used. Unfortunately, I couldn't find anything, even if I've done quite an extensive

On-line survey

2000-07-13 Thread Bob Hayden
While I agree that online surveys are of dubious value, some of the opposition sounds too moralistic or contentious for my taste. Here is a parable. The usual formulae of inferential statistics estimate the error made by using a random sample instead of a census. If you did not take a random

Re: On-line survey

2000-07-13 Thread Bob Hayden
- Forwarded message from George W. Cobb - I don't disagree at all with Bob's point (there goes another chance to be contentious!) but you can sometimes go a long way using the right simplifying assumptions. Here's the reference: O'Conner, M.P., and J.R. Spotilla (1992). "Consider a

Re: On-line survey

2000-07-16 Thread Bob Hayden
- Forwarded message from Dale Berger - Thank you for many useful comments and suggestions regarding on-line data collection. Several people expressed concerns about the quality of data collected on-line, even to the point of categorically denouncing the technique. On-line surveys

bump hunting in nonlinear regression

2000-07-18 Thread Bob Hayden
- Forwarded message from Daniela Ichim - In a nonlinear (univariate) regression problem, specifically a calibration problem in thermometrics, I have the problem of testing whether a curve expressing a relationship between Electrical Resistance and Temperature is monotone versus the

ensuring confidentiality

2000-08-03 Thread Bob Hayden
You must have a different audience than I if you think they can spell other people's names, remember numbers, identify and encode playing cards, know their mother's maiden name and birthdate, etc. The task needs to be one they are capable of and motivated to attempt. Maybe the survey could

Re: ensuring confidentiality (fwd)

2000-08-04 Thread Bob Hayden
- Forwarded message from Peter Lewycky - I've yet to meet an (adult) respondent who did not know his mother's maiden name and her birthdate. :) - End of forwarded message from Peter Lewycky - We must meet sometime!-) _ | |Robert W. Hayden

Re: t-test normality assumption

2000-08-06 Thread Bob Hayden
Selections from an earlier exchange on EdStat-L are followed by some comments. - Forwarded message from Donald Burrill - On Sat, 5 Aug 2000, Gates, Christopher [OMP] wrote: Donald, thank you so much for your response. I had the opportunity to converse with my friend (HOH) on this

Re: a fortiori

2000-08-07 Thread Bob Hayden
- Forwarded message from [EMAIL PROTECTED] - My American Heritage Talking Dictionary on CD not only looked up said latinism, but spoke it as well. Its corrected a number of pronunciations for me. Most recently schism.In some cases it displays a picture or map. I couldn't

part-time pay

2000-08-08 Thread Bob Hayden
Part-time lecturers are underpaid everywhere. Let's not all dump on BU who is paying them better than most places do. -- _ | |Robert W. Hayden | | Work: Department of Mathematics / |Plymouth State College MSC#29 | |

RE: a fortiori

2000-08-12 Thread Bob Hayden
- Forwarded message from Olsen, Chris - Hello Bob and All -- I think SOME long phrases are discussed in The Browser's Dictionary, by John Ciardi. I don't know if it is still in print, but it is authoritative and fascinating. (Perhaps not a lot of statistical terms and phrases,

definition of bar chart

2000-08-12 Thread Bob Hayden
- Forwarded message from Alexander Bogomolny - The Harper Collins Dictionary of Mathematics gives the following definitions: 1. Histogram - a figure that represents a frequency distribution, consisting of contiguous rectangles with width proportional to the size of the respective class

take up burglary

2000-08-12 Thread Bob Hayden
I just sent out a posting and immediately got back three automated messages from people saying they are away. This gave me a great idea for making money off the Internet -- set up a network for house burglars! You join every list in sight and send a nonsense message to them all. Then you

Re: teaching software for stats/maths

2000-08-23 Thread Bob Hayden
- Forwarded message from Ken - Another helpful tool to consider is the Standard Deviants Statitics video tape series. You can purchase it through www.amazon.com - search using "standard deviants statistics". (yes I mean deviants and not deviates). They are VERY good tapes intended to

datasets for Siegel and Morgan

2000-08-23 Thread Bob Hayden
I have added the PSC datasets for Siegel and Morgan to my website in Statland. These are not the files that come on the disk from the publisher but rather the data for nearly every example, problem or exercise in the book -- about 375 files. My favorites are the raw data files for the

Re: Referencing MINITAB in a scientific publication (fwd)

2000-08-25 Thread Bob Hayden
- Forwarded message from dennis roberts - would one reference microsoft word in the paper? i am not sure one has to reference the stat package ... or, if you were doing it using a spreadsheet like excel ... would you reference that? if you do want to say anything ... just say that

Skewness and Kurtosis Questions

2000-08-28 Thread Bob Hayden
- Forwarded message from Ronny Richardson - Several references I have looked at define skewness as follows: mean median: positive, or right-skewness mean = median: symmetry, or zero-skewness mean median: negative, or left-skewness - End of forwarded

[ap-stat] Re: stat packages NCSS

2000-09-09 Thread Bob Hayden
- Forwarded message from Thomas Gatliffe - NCSS has had all these capabilities for the last 10 years. You must have been looking a long time ago. If your objective is both low-sweat statistics and good, fully-customizable graphics, check out NCSS. I'm a big fan of NCSS, although I

Re: job issues. stat and computer?

2000-09-27 Thread Bob Hayden
- Forwarded message from [EMAIL PROTECTED] - Many of these people end up as SAS programmers. Lots of experience wtih SAS may be more valuable than abstract computer science. I did take some computer science courses while taking my stats degree. If you know the fundamentals of

Re: memorizing formulas

2000-10-09 Thread Bob Hayden
- Forwarded message from Michael Granaas - I honestly believe that there is something to be learned from memorizing several of the basic formulas that are involved in defining statistics. I, less elegantly, tell my students that it is important to have this basic understanding so that

Re: multiplicative rule

2000-10-22 Thread Bob Hayden
- Forwarded message from Bill Jefferys - In article [EMAIL PROTECTED], [EMAIL PROTECTED] (dennis roberts) wrote: #so, what does the multiplicative "law" in probability mean then? If A is an event and B is an event, then the probability of the event AB is given by P(AB)=P(A)P(B) in


2000-10-23 Thread Bob Hayden
Jerry Dallal wrote: I have a note from Frank Anscombe in my files. It says, "Cardano. See the bit from "De Vita Propria" at the head of Chap. 6 of FN David's "Games, Gods, and Gambling (1962). That shows that the idea of a test of significance, informally described, is very ancient." I

Re: How to pronounce Kolmogorov

2000-10-25 Thread Bob Hayden
- Forwarded message from ?? - on the third syllable [kalma' gorov] - End of forwarded message from ?? - I need help breaking "kalma" into three syllables?-) _ | |Robert W. Hayden | | Work:

Re: Winsorisation: who was Winsor ?

2000-10-27 Thread Bob Hayden
- Forwarded message from Bob Wheeler - Charles Payne Winsor (It might be "Paine".) He died in the early 50's. There was a biography in the American Statistician, I think. Rich Ulrich wrote: ("Could anyone suggest references for me ...?" would be a gentler way to request

Palm Beach Stats

2000-11-10 Thread Bob Hayden
- Forwarded message from Reg Jordan - None of these issues (double punching, voting for wrong candidate) were raised at the polling place at the time of voting. - End of forwarded message from Reg Jordan - How do you know that? NPR interviewed one woman who realized she might

Re: Help needed ... :-(

2000-11-13 Thread Bob Hayden
- Forwarded message from David Heiser - - Original Message - From: Dennis [EMAIL PROTECTED] Hello Newsgroup, I'm searching for real good books on stats. I'm a student of psychology and we've been taught very much stats. But I read all the time your postings and wonder why

Fwd: Butterfly ballots (fwd)

2000-11-14 Thread Bob Hayden
- Forwarded message from by way of Tom Lane [EMAIL PROTECTED] - From [EMAIL PROTECTED] Tue Nov 14 10:03:28 2000 Return-Path: [EMAIL PROTECTED] Received: from smtp.mathworks.com (turing.mathworks.com []) by oz.plymouth.edu (8.10.2/8.10.0) with ESMTP id eAEF3Rb98330


2000-11-15 Thread Bob Hayden
1. The attention focussed on Florida seems to be partly an abberation of the electoral system and the miscalls in the media. (If we went by popular vote then there would be no point in trying to call a state.) Florida is in the spotlight partly because of the close vote there, partly because

math. editors

2000-11-20 Thread Bob Hayden
I have been looking at math. editors for years. There's no right answer -- it just depends on what you want to do. For example, the journals of the American Mathamatical Society want you to submit articles in TeX or LaTeX, which is the most powerful tool for such things, but also the hardest

math. symbols

2000-11-20 Thread Bob Hayden
- Forwarded message from Paul W. Jeffries - What software would you recommend for writing documents that contain mathematical symbols? Microsoft Word does not have all the symbols I need. - End of forwarded message from Paul W. Jeffries - If it is just a matter of symbols you

Re: Software (fwd)

2000-11-29 Thread Bob Hayden
- Forwarded message from Ken - Of course you'll get what you pay for. "Comet" [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... I search a good and free:) sofware of stat - End of forwarded message from Ken - When I installed Win98 on my computer

Florida votes and statistical errors

2000-11-30 Thread Bob Hayden
- Forwarded message from Gene Gallagher - There seems to be some misunderstanding in the press about a fundamental difference between a sample of a larger population and a complete census. - End of forwarded message from Gene Gallagher - Possibly, but I don't think the Florida

Re: Florida votes and statistical errors (fwd)

2000-12-09 Thread Bob Hayden
- Forwarded message from [EMAIL PROTECTED] - Since the vote difference between Bush and Gore falls within the margin of error for the counting process, declaring the winner is mathematically indeterminable within any reasonable degree of scientific confidence. Since we cannot know who

Re: help with modelling

2000-12-17 Thread Bob Hayden
- Forwarded message from Herman Rubin - The model must come from the investigator, not from the data. Data only helps to choose between models, estimate parameters, and related questions. - End of forwarded message from Herman Rubin - Actually, I think the apparent conflict

The Margin-of-Error Fallacy

2000-12-23 Thread Bob Hayden
- Forwarded message from Jake - Most of us feel that we know what "margin of error" means but to make sure we're all on the same page, let's review. "Margin of error" is a term out of survey polling that refers to the confidence we have in the results of a given survey. In general, the


2000-12-29 Thread Bob Hayden
Anybody have anything to say about statistical education??? -- _ | |Robert W. Hayden | | Work: Department of Mathematics / |Plymouth State College MSC#29 | |Plymouth, New Hampshire 03264 USA | * |

Scale on survey questionnaire (fwd)

2001-01-04 Thread Bob Hayden
- Forwarded message from [EMAIL PROTECTED] - Hi I need some professional advice on a statistics question. I recently took part in a survey where the scale of responses was given as: Agree / Tend to Agree / ? / Tend to Disagree / Disagree The question mark in the middle seems very


2001-01-05 Thread Bob Hayden
An example might shed some light on one point involved here. Recently Plymouth State College considered the possibility of arming -- well, part of the question was WHOM. Many of us refered to them as Campus Security while they insisted they were Campus Police. Looking at old phone books it

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: Most Common Mistake In Statistical Inference

2001-03-22 Thread Bob Hayden
Re assumptions for inference... - Forwarded message from Robert J. MacG. Dawson - What is needed in the small-sample case is outside _knowledge_ (not "well, it _might_ be true" or "in this discipline we usually assume..." assumptions!) about the distribution - without this we should not

survey questionnaire software??

2001-03-26 Thread Bob Hayden
Forwarding a query. Reply to mland, not to me. Margaret Land, Ph.D. StatisticsMSC 172 Texas AM University-Kingsville Kingsville TX 78363-8201 fax 361-593-3518 tel 361-593-2235 [EMAIL PROTECTED] Has


2001-04-02 Thread Bob Hayden
I checked with a nerdy geek and was told that it is a waste of bandwidth to broadcast attachments to an entire mailing list. Although not every attachment is a virus, NO ASCII text is. Dr. Knodt's suggestion is entirely consistent with email etiquette. - Forwarded message from Thomas