Re: Applied analysis question

2002-03-03 Thread Rich Ulrich
On 28 Feb 2002 07:37:16 -0800, [EMAIL PROTECTED] (Brad Anderson) wrote: Rich Ulrich [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED]... On 27 Feb 2002 11:59:53 -0800, [EMAIL PROTECTED] (Brad Anderson) wrote: BA I have a continuous response variable that ranges from 0 to 750

Re: help on factor analysis/non-normality

2002-03-01 Thread Rich Ulrich
of non-normality. Please do give references if you are replying. Thanks. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem

Re: Robust regression

2002-03-01 Thread Rich Ulrich
, but not the normality of raw scores. So does it help at all to use robust regression in this situation. Any help will be appreciated. Go ahead and do it if you want. If someone asks (or even if they don't), you can tell them that robust regression gives exactly the same result. -- Rich Ulrich

Re: Applied analysis question

2002-02-28 Thread Rich Ulrich
On 27 Feb 2002 14:14:44 -0800, [EMAIL PROTECTED] (Dennis Roberts) wrote: At 04:11 PM 2/27/02 -0500, Rich Ulrich wrote: Categorizing the values into a few categories labeled, none, almost none, is one way to convert your scores. If those labels do make sense. well, if 750 has

Re: Means of semantic differential scales

2002-02-26 Thread Rich Ulrich
. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at http

Re: Evaluation of skating

2002-02-22 Thread Rich Ulrich
2 1 3 4 5 7 6 8 9 12 11 13 10 15 14 16 17 19 18 20 Japan end data. execute. flipnewnames= judge. formats russia to japan(F2.0). listall. subtitle'Spearman' is the Pearson corr. compute ranked= $casenum. nonpar corr vars= russia to japan ranked /print=both. -- Rich

Re: How to test whether f(X,Y)=f(X)f(Y) is true??

2002-02-21 Thread Rich Ulrich
be different from detecting lines. As I wrote before , So there is an infinite variety of tests conceivable. So the *useful* test is the one that avoids 'Bonferroni correction, because it is the one you perform because you have some reason for it. -- Rich Ulrich, [EMAIL PROTECTED] http

Re: SPC control limits

2002-02-20 Thread Rich Ulrich
yourself a failing grade -- based on guilt-feelings rather than on data -- and change the limits without ever testing whether there is a real problem. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: How to test whether f(X,Y)=f(X)f(Y) is true??

2002-02-20 Thread Rich Ulrich
le. So the *useful* test is the one that avoids 'Bonferroni correction, because it is the one you perform because you have some reason for it. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Inst

Re: covariates !!

2002-02-19 Thread Rich Ulrich
) with ANOVA vara by grps(1,4) with covar/ -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives

Re: can multicollinearity force a correlation?

2002-02-19 Thread Rich Ulrich
R^2 of 2% -- so I am sure they don't represent *that* relationship in a proper way. My tentative conclusion is that your 2% effect really is a small one; it should be difficult to discern among likely artifacts; and therefore, it is hardly worth mentioning -- Rich Ulrich, [EMAIL

Re: Numerical recipes in statistics ???

2002-02-19 Thread Rich Ulrich
of matrices, so you know when it is, that you want to get an eigenvector; and what to do with it. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about

Re: Newbie question

2002-02-17 Thread Rich Ulrich
deviation is the standard deviation of the sample. We say that the standard deviation of the sample *mean* will be frequently referred to as the standard error; and The SD of the mean [or the SE] equals SD/sqrt(N). That is confusing enough. I hope this makes your sources clear. -- Rich

Re: If T-Test can not be applied

2002-02-15 Thread Rich Ulrich
is not reliable or robust for 'superiority.' You can compute some Robust tests, such as the 2x2 contingency test, which may be based on median split or whatever split meets your needs. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: homogeneity of variance

2002-02-15 Thread Rich Ulrich
'exact procedures' that may have been designed for unequal N, generically.) Personally, I try to do important tests and avoid Bonferroni. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: can multicollinearity force a correlation?

2002-02-15 Thread Rich Ulrich
usually are not). -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available

Re: one-way ANOVA question

2002-02-14 Thread Rich Ulrich
told us before, you don't appreciate hypothesis testing ... I thought you could not think of cases where doing *any* F-test helps us. [ ... ] -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: Ansari-Bradley dispersion test.

2002-02-10 Thread Rich Ulrich
://franz.stat.wisc.edu/~rossini/courses/intro-nonpar/text/Specifications_for_the_Ansari_Bradley_Test.html I suggest repeating the search. That also eliminates the pasting problem if your reader has broken the long URL into two lines. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Book/textbook on applied math with expectation/variance

2002-02-10 Thread Rich Ulrich
. Or look in the same section of the library as KS; or whatever sources you have liked before. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about

Re: time series analysis

2002-02-07 Thread Rich Ulrich
of particular references for what I have been talking about, but unbalanced data might help your search. And you could try us with more detail, if you wish. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Case-cross over

2002-02-07 Thread Rich Ulrich
is available. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available

Re: EViews 3.1 error message

2002-02-07 Thread Rich Ulrich
to start from scratch. Can you re-import your data from Excel? That sounds safe, even if you create it in Excel by exporting from 4.0. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: can multicollinearity force a correlation?

2002-02-07 Thread Rich Ulrich
for 'confounding' or 'masking'; and there might be something more in my own stats-faq. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about

Re: Sensitivity Analysis

2002-02-06 Thread Rich Ulrich
in genetic model ling -- makes me think of something I saw years ago, called 'perturbation analyses'. Try Google, or try us again with additional detail. Hope this helps. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Interpreting mutliple regression Beta is only way?

2002-02-05 Thread Rich Ulrich
its zero-order beta. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available

Re: The exam questlons will probably be tougher

2002-02-03 Thread Rich Ulrich
). There were only 67 for statistics practice problems, some of them designed for a particular class's test. Quick inspection shows that the latter two words should be promising. statistics practice problems nets 7420, so you might be able to select topics within those. -- Rich Ulrich, [EMAIL

Re: Verba Volant 31-01-02 SPAM

2002-01-31 Thread Rich Ulrich
Postmaster, Would you please tell your User that they have to stop sending their daily message to Usenet Newsgroups. Below are the headers, and the contents of what was received today, at sci.stat.edu. Rich Ulrich, [EMAIL PROTECTED] == headers and message (raw plus HTML plus encoded) Path

Re: Verba Volant 31-01-02 SPAM

2002-01-31 Thread Rich Ulrich
On Thu, 31 Jan 2002 10:37:13 -0500, Rich Ulrich [EMAIL PROTECTED] wrote: Postmaster, Would you please tell your User that they have to stop sending their daily message to Usenet Newsgroups. Below are the headers, and the contents of what was received today, at sci.stat.edu. Rich

Re: area under the curve

2002-01-30 Thread Rich Ulrich
, for any measure of accuracy. I think I would find it interesting to see some Monte Carlo experiments. I think those should start with specific classes of distributions, and specific ranges for their parameters, and plot their 'accuracies' against the observed skewness and kurtosis. -- Rich Ulrich

Re: factor Analysis

2002-01-29 Thread Rich Ulrich
several derived factors. (For a set of items where many items were new and untested, it can be appropriate to discard some of items -- where the loadings were split, or were always small.) Each factor is scored as the average score for of a subset of items. -- Rich Ulrich, [EMAIL PROTECT

Re: cutting tails of samples

2002-01-29 Thread Rich Ulrich
by 5% or 10% reportedly works well for your measures of 'central tendency', so long as you *know* that the extremes are not important. I don't know what it is that you refer to as 'enterprise data.' -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: coefficient in logistic regression

2002-01-25 Thread Rich Ulrich
you have. If you have more question, copy some output for us; send some set-up lines; and mention what program. Also, you posted many, many lines of HTML; please turn off that option if you can figure out how. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Interpreting mutliple regression Beta is only way?

2002-01-25 Thread Rich Ulrich
On 18 Jan 2002 16:55:11 -0800, [EMAIL PROTECTED] (Wuzzy) wrote: Rich Ulrich [EMAIL PROTECTED] wrote in message Thanks Rich, most informative, I am trying to determine a method of comparing apples to oranges - it seems an improtant thing to try to do, perhaps it is impossible . Well, I do

Re: QUERY on multiple linear regression: predicted values show much smaller ranges

2002-01-24 Thread Rich Ulrich
of a regression statistic that directly tells me that; maybe I should create one.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem

Re: analyzing counts from ordered categories

2002-01-23 Thread Rich Ulrich
test, but I am not sure whether it would fit.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES

Re: 95% CI for a sum

2002-01-22 Thread Rich Ulrich
(A) + Var(B)for A,B independent; and Var(kA) = k^2 Var(A) Right? The SE is the SD of the mean, so you have the terms you need. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: how to adjust for variables

2002-01-22 Thread Rich Ulrich
the statement when it appears. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available

Re: Likelihood ratios and non-nested models

2002-01-20 Thread Rich Ulrich
comparison of link functions sounds familiar, for instance. Here is one link I found by searching on BIC information criterion , http://www.saam.com/faq/saam2/right.html (I keep forgetting how to spell AKAIKE.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: a problem

2002-01-16 Thread Rich Ulrich
confusing, borrow a book or two on experimental design and spend time on the earliest chapters. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about

Re: Interpreting mutliple regression Beta is only way?

2002-01-16 Thread Rich Ulrich
this helps. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available

Re: Empirical data Fitting

2002-01-15 Thread Rich Ulrich
for normality when you compare correlations across a range of deviant samples. I don't remember its analog being used for testing between theoretical CDFs; and I suspect it is inferior to other approaches for (say) strongly skewed distributions. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu

Re: Buy Book on Probability and statistical inference

2002-01-13 Thread Rich Ulrich
of people who answer questions in the stat-groups, and look for references and links to references. Hope this helps. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving

Re: SAT Question Selection

2002-01-13 Thread Rich Ulrich
journal produced by ETS when I was looking up references for scaling, a year or so ago. But I don't remember that for a fact. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining

Re: what is the appropriate method?

2002-01-10 Thread Rich Ulrich
On Thu, 10 Jan 2002 12:00:06 +0100, Jos Jansen [EMAIL PROTECTED] wrote: Rich Ulrich [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Wed, 09 Jan 2002 08:33:41 GMT, [EMAIL PROTECTED] (Jukka Sinisalo) wrote: We have two pots with 25 pla

Re: Chart of the Week

2002-01-09 Thread Rich Ulrich
it seemed in the news item) concluded that Winners should go on to be more successful... but die younger. And further speculation. My interest faded before I looked it all up. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: what is the appropriate method?

2002-01-09 Thread Rich Ulrich
-transform, the CIs are never improper. The logit is log( p/(1-p) ) You can't compute LOG if the survivorship is ever 0 or 100%. Folks usually plug in 0.5 for 0 cases when that happens. (Starting with 25 plants, plug in 2% or 98% for 0 or 100%.) -- Rich Ulrich, [EMAIL PROTECTED] http

Re: Is there a problem with this kind of comparison?

2002-01-04 Thread Rich Ulrich
% of all errors were one kind, so you were trying to bring that one sort down. Hope this helps. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list, remarks

Re: Empirical data Fitting

2002-01-03 Thread Rich Ulrich
case?? ... Other that statistical? - Being familiar; being logically inherent; being brief... Occam's razor goes something like this, Do not unnecessarily multiply entities in an explanation. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: One-tailed, two-tailed

2002-01-02 Thread Rich Ulrich
On Sun, 30 Dec 2001 18:07:16 -0500, [EMAIL PROTECTED] (Stan Brown) wrote: Rich Ulrich [EMAIL PROTECTED] wrote in sci.stat.edu: [ ... ] RUWe should not overlook the chance to teach our budding statisticians: *Always* pay attention to the distinction between random trials or careful

Re: One-tailed, two-tailed

2001-12-30 Thread Rich Ulrich
for any enlightenment. (If you send me an e-mail copy of a public follow-up, please let me know that it's a copy so I know to reply publicly.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: How ro perform Runs Test??

2001-12-27 Thread Rich Ulrich
appeals most to you. The D-W test is awkward enough to *test* that you don't wonder why people should look for an easier option. Several textbooks that I just looked at seem to be satisfied with recommending that you eye-ball your residuals in several plots - without doing tests. -- Ric

Re: Is this how you would have done it?

2001-12-27 Thread Rich Ulrich
categories, and choose the few that matter to themselves. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE

Re: What is the formulae for generalised Gaussian CDF???

2001-12-21 Thread Rich Ulrich
search on generalized gaussian; so, you can probably find others. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE

Re: Transaction Anomaly on 9/11????

2001-12-18 Thread Rich Ulrich
. And investigators looked. I'm sorry, but this post reads to me like a pandering to hostile paranoia, and that annoys me; so I won't say anything more. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: chi square validity?

2001-12-18 Thread Rich Ulrich
describe one cell's contribution versus the others. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES

Re: Evaluating students: A Statistical Perspective

2001-12-13 Thread Rich Ulrich
they are sliding away from lifetime employment, etc., I wonder if the educational system is becoming more flexible and technocratic, too. Are our systems converging? -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: When to Use t and When to Use z Revisited

2001-12-10 Thread Rich Ulrich
is known, so the test statistic has the shorter tails. (It works for ranks when you don't have ties.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks

Re: What usually should be done with missing values when I am conducting a t test or other tests?

2001-12-07 Thread Rich Ulrich
do you happen to have data like these? - If there is a Why, you need to find out Why; else, you want to educate them to do better next time. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: Evaluating students: A Statistical Perspective

2001-12-06 Thread Rich Ulrich
Just in case someone is interested in the Harvard instance that I mentioned -- while you might get the article from a newsstand or a friend -- On Sun, 02 Dec 2001 19:19:38 -0500, Rich Ulrich [EMAIL PROTECTED] wrote: [ ... ] Now, in the NY Times, just a week or two ago. The dean

Re: What usually should be done with missing values ...

2001-12-05 Thread Rich Ulrich
On Tue, 04 Dec 2001 17:39:53 GMT, Jerry Dallal [EMAIL PROTECTED] wrote: Rich Ulrich wrote: [ ... ] I don't see much difference. Identifying predictors by regression analyses -- what is that advice supposed to mean? The criticisms of stepwise selection say that it gives you

Re: When does correlation imply causation?

2001-12-05 Thread Rich Ulrich
implies causation - intuitively, or - naively, or - in the weak sense. (I admit it -- I see a sexy correlation and 'implications' cross my mind.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Important notice about Final Exam on Thursday

2001-12-05 Thread Rich Ulrich
; that was (after all) a partial-beta. What am I missing? -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE

Re: What usually should be done with missing values ...

2001-12-04 Thread Rich Ulrich
On Mon, 03 Dec 2001 20:57:33 GMT, Jerry Dallal [EMAIL PROTECTED] wrote: Rich Ulrich wrote: On 2 Dec 2001 16:49:25 -0800, [EMAIL PROTECTED] (Kevin C. Heslin) wrote: Jenny -- here's a way to impute continuous variables using SAS: Regression analysis is performed on a continuous

Re: KS Statistic and adjustments

2001-12-04 Thread Rich Ulrich
that you need to make decisions about). -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available

Re: What usually should be done with missing values ...

2001-12-03 Thread Rich Ulrich
- until significant predictors of the continuous variable are identified. That does limit the exercise to being strictly exploratory. You can see my stats-FAQ (or groups.google search) for criticisms of stepwise selection. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib

Re: Interpreting p-value = .99

2001-12-02 Thread Rich Ulrich
On Sat, 1 Dec 2001 08:20:45 -0500, [EMAIL PROTECTED] (Stan Brown) wrote: [cc'd to previous poster] Rich Ulrich [EMAIL PROTECTED] wrote in sci.stat.edu: I think I could not blame students for floundering about on this one. On Thu, 29 Nov 2001 14:39:35 -0500, [EMAIL PROTECTED] (Stan Brown

Re: Interpreting p-value = .99

2001-11-30 Thread Rich Ulrich
as effective for 90% of the people. I wondered if the asterisk was supposed to represent [sic]. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about

Re: (none)

2001-11-30 Thread Rich Ulrich
? Have you tried the 2nd Edition of Cohen's book (1989 or 90) on power analysis? (The 1st and Revised editions don't have the final chapter or two.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Normal distribution

2001-11-29 Thread Rich Ulrich
independent z variates is chi squared with S degrees of freedom. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE

Re: t vs. z - recapitulation

2001-11-29 Thread Rich Ulrich
, Mann-Whitney is not a good alternative (assumes symmetric distrib.), right? [ ... ] It assumes *same* distributions in two samples, not necessarily symmetric. What is your hypothesis going to be? What can you fairly conclude, if one sample occupies both ends of the distribution? -- Rich

Re: Normal distribution

2001-11-29 Thread Rich Ulrich
On Thu, 29 Nov 2001 14:37:14 -0400, Gus Gassmann [EMAIL PROTECTED] wrote: Rich Ulrich wrote: On Thu, 29 Nov 2001 15:48:48 +0300, Ludovic Duponchel [EMAIL PROTECTED] wrote: If x values have a normal distribution, is there a normal distribution for x^2 ? If z is standard normal

Re: biostatistics careers

2001-11-26 Thread Rich Ulrich
. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =

Re: When Can We Really Use CLT Student t

2001-11-21 Thread Rich Ulrich
scanned textbooks in search of errors like those, but I hardly ever find any. Gross mis-statements tend to be in handbooks and in (unfortunate) interpretative articles by non-statisticians. (Can you cite chapter and verse?) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib

Re: best inference

2001-11-21 Thread Rich Ulrich
finally achieved a p-value, and wonder what to do next. (Actually, I don't have a quick opinion, but I thought Promoting Tests was a good way to pull Dennis's leg.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: biostatistics careers

2001-11-19 Thread Rich Ulrich
. [ ... ] === end of 1998 citation -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available

Re: [HELP NEEDED] What is the best technique to analyze the following experiment?

2001-11-18 Thread Rich Ulrich
suspect that data, as stated, leave out some conventional standardization, and so the observed correlations are mainly artifacts. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining

Re: Fw: We need your help!!!

2001-11-13 Thread Rich Ulrich
-abstracts.html The Best Test for Interaction in Factorial ANOVA and ANCOVA Todd C. Headrick and Shlomo S. Sawilowsky Wayne State University I wonder... Isn't an education, these days, supposed to develop the ability to go online and search for topics like these? -- Rich Ulrich, [EMAIL PROTECTED] http

Re: Standard Deviation!

2001-11-12 Thread Rich Ulrich
the standard deviation is increased. But this is a silly problem to me because I don't make any sense out of 'standard deviation.' -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining

Re: Testing for joint probability between 2 variables

2001-11-01 Thread Rich Ulrich
. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =

Re: ranging opines about the range

2001-10-31 Thread Rich Ulrich
is a sizable correction, someone needs to speak carefully about the 'range.' To put it another way: If all the cases all are observed at the same value, and it matters, then the audience really does deserve to hear the details. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Graphics CORRESPONDENCE ANALYSIS

2001-10-24 Thread Rich Ulrich
my impression (from google) that CA is more popular in European journals than in the US, so there might be better sites out there in a language I don't read. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Standardized Confidence Intervals

2001-10-21 Thread Rich Ulrich
. How variable is this group? How extreme is this group and sample (if it is a clinical trial)? A small N is especially problematic, since you do want to show how narrowly (or not) it was selected. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Transformation function for proportions

2001-10-19 Thread Rich Ulrich
27, 2001, Jez Hill. Subject: Re: [Q ] transforming binomial proportions Newsgroups: sci.stat.math Rich Ulrich wrote in article [EMAIL PROTECTED]: The fixed variance was the main appeal of the approximation, arcsin(sqrt(p)). [snip] A more accurate transformation for small n has been tabulated

Re: Transformation function for proportions

2001-10-18 Thread Rich Ulrich
that is ordinarily additive. I have not seen many texts that tackle transformations in the abstract. Finney's classic text on bioassay has a few pages. Or, I think, Mosteller and Tukey, Data Analysis and Regression. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Help for DL students in doing assignments

2001-10-15 Thread Rich Ulrich
by me (a native speaker of English), If K and L are *any* two primes, and S is any even number, it is true that S = K+L . That is true for arithmetic-modulo-2. Otherwise, not. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: Are parametric assumptions importat ?

2001-10-14 Thread Rich Ulrich
opinion. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http

Re: Help for DL students in doing assignments

2001-10-10 Thread Rich Ulrich
. with detailed solutions descriptions ... Since English is not his native language, perhaps his degree *is* one degree that included all four. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions

Re: Logistic Regression vs Chi Square test in the following scenario

2001-10-02 Thread Rich Ulrich
your marginals are *not* both fixed. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available

Re: optimal sample size

2001-10-02 Thread Rich Ulrich
, for a few hundred years. A lot of people know what statistical power is, and there is no controversy as to shape of the general topic. So you need a more specific question. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: no subject

2001-10-01 Thread Rich Ulrich
and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = -- end message -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: optimal sample size

2001-10-01 Thread Rich Ulrich
problematic word. Another problem is that you seem to ask about all research, in all of the world It might be a clever way to attack 'sample size', but I think that hasn't been done. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: E as a % of a standard deviation

2001-09-30 Thread Rich Ulrich
percentage, I often find it easier to think of the number-of-instances. One percent of 4000 is 40. What is the accuracy with 40 seen in the sample? (95% CI is wider than 30 to 50, but not by a whole lot.) -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html

Re: what type of distribution on this sampling

2001-09-23 Thread Rich Ulrich
that your means will not be normal, or be very useful compared to some other description. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about

Re: Regression to the mean,Barry Bonds HRs

2001-09-23 Thread Rich Ulrich
accounts for some placebo effect, I'm afraid that I think that it happens that he was wrong about the particular article on Placebo-effect -- if that is the one that we discussed a few months ago. - see my other response today on this thread (which I intend to write, immediately). -- Rich Ulrich

Re: how to compare generated values with the specified distribution basis

2001-09-20 Thread Rich Ulrich
tests (like the MWW), and (b) simple t-tests, etc., on the rank-transformations. Robert waffles by saying 'most' purposes, so I have to find it easy to agree. When might you *not* treat a uniform, N=20 as normal? - perhaps when the R^2 is too high (above .90)? -- Rich Ulrich, [EMAIL

Re: Free program to generate random samples

2001-09-20 Thread Rich Ulrich
numbers. Um. A sample of 100 from a population of 100 is going to give you the entire population. Um^2. Only if you sample without replacement. Probably: google for bootstrap macro stat-program . I know there are examples for SPSS and SAS. -- Rich Ulrich, [EMAIL PROTECTED

Re: how to compare generated values with the specified distribution basis

2001-09-20 Thread Rich Ulrich
. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http

Re: Definitions of Likert scale, Likert item, etc.

2001-09-20 Thread Rich Ulrich
- about the citation; and some musing. On 19 Sep 2001 18:11:59 -0700, [EMAIL PROTECTED] (dennis roberts) wrote: At 05:14 PM 9/19/01 -0400, Rich Ulrich wrote: It has Likert's original observations on writing an attitude scale (1932, which I had not seen elsewhere). dmr likert's work

Re: Definitions of Likert scale, Likert item, etc.

2001-09-19 Thread Rich Ulrich
As I was saying a few days ago - On Sun, 16 Sep 2001 17:37:55 -0400, Rich Ulrich [EMAIL PROTECTED] wrote: [ ... ] It is often useful to read what is published in several textbooks. Sometimes old textbooks have as much to say as new textbooks do, if the old ones don't assume so many answers

Re: Regression to the mean,Barry Bonds HRs

2001-09-18 Thread Rich Ulrich
in statistics beyond their understanding of math? Ph.D. psychologists. (And many economists, but they are not relevant here.) It's those PhD psychologists who *I* would expect to cavalierly misunderstand, mis-state, or misuse regression to the mean, in either direction. -- Rich Ulrich, [EMAIL

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