Please help

2001-05-04 Thread Adil Abubakar

My name is Adil Abubakar and i am a student.and seek help .  I have a
question if anyone can help, please respond to
[EMAIL PROTECTED]

Person A did  research on a total of 4500 people and got the follwoing
results
Q How many hours do you spend on the web
0-7 8-15  15+
18%   48%   34%
   Q. Do you read a privacy policy before signing on to a web site
   The answers were

   1= Strongly Agree 2= Agree 3= Neutral 4= disagree 5= strongly
disagree

   9%  17%   20%32% 22% respectively

Another person asked the the same questions from a 100 people and got
the same results in % terms?  Can it be shown via CI that the result is
consitent with the expectations created by the previous survey?
Also can it be argued that the subjects have been subjected to the
questions before.

can it be asserted with statiscal significance , that if the survey is
repeated on at least 100 people the result will in the same proximity of

the above survey??

 any help ya'll can provide will be appreciated  Just the need different

methodlogies

   Thanking you in anticipation

   Adil Abubakar
[EMAIL PROTECTED]





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Estimating priors for Bayesian analysis

2001-05-04 Thread Will Hopkins

I've gone to a lot of trouble to add Bayesian adjustment in a spreadsheet 
for estimating confidence limits of an individual's true score when the 
subject is assessed with a noisy test.  I specify the prior belief simply 
by stating a best guess of the true score, and its x% likely limits, with 
assumption of normality.  I now realize that the adjustment is sensitive to 
the value of x, but how does a person know what x is for a given belief?

For example, I might believe that the individual's true score is 70 units, 
and that the likely range is +/- 10 units.  So what describes 
likely?  90%, 95%, 99%...?  Do Bayesians have any validated way to work 
that out?  If they don't, then the whole Bayesian edifice might just come 
crashing down.  I put this to a Bayesian who has been helping me, but I 
have received no reply from him since I sent the message, so I suspect the 
worst.

Will



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Re: Orthogonality of Designs for Experiments

2001-05-04 Thread Herman Rubin

In article [EMAIL PROTECTED],
Jeff [EMAIL PROTECTED] wrote:
Hello,

Would like to ask the design of experiment gurus to help me with the 
following questions:

1. why designs for experiments should be orthogonal ?

The computations get easier.

2. which problems may I encounter if I use non-orthogonal design ?

The nice simple ANOVA procedures are no longer valid.
This does not mean that nothing can be done.
-- 
This address is for information only.  I do not claim that these views
are those of the Statistics Department or of Purdue University.
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399
[EMAIL PROTECTED] Phone: (765)494-6054   FAX: (765)494-0558


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Re: Combinometrics

2001-05-04 Thread Jerry Dallal

Herman Rubin wrote:
 I also doubt
 whether learning to compute answers gives any insight
 into the concepts, except for those with good research
 potential, and even there it tends to confuse.

It depends on what learning to compute means.  (*I'm* saying this
in repsonse to a comment from Prf. Rubin?!)

Consider exp(i pi).
I can compute it by using Euler's rule or by viewing it as the pi
radians rotation of a rod of unit length in the imaginary plane.

Or consider the variance.  I can compute it by using the desk
calculator algorithm or by summing the squares of deviations.

If learning to compute means simply that one is given a formula--any
formula--that is to be used without any thought of its origins, I
agree.
OTOH, thoughts about the method of computation can often lead to
important insights.


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Re: errors in journal articles

2001-05-04 Thread jim clark

Hi

On 3 May 2001, Warren Sarle wrote:
 Joel Best is a professor of sociology and criminal
 justice at the University of Delaware. This essay is
 excerpted from _Damned Lies and Statistics:
 Untangling Numbers From the Media, Politicians, and
 Activists_, just published by the University of
 California Press 
 So the prospectus began with this (carefully footnoted)
 quotation: Every year since 1950, the number of American
 children gunned down has doubled. I had been invited to
 serve on the student's dissertation committee. When I read
 the quotation, I assumed the student had made an error in
 copying it. I went to the library and looked up the article
 the student had cited. There, in the journal's 1995 volume,
 was exactly the same sentence: Every year since 1950, the
 number of American children gunned down has doubled.
 This quotation is my nomination for a dubious distinction: I think it may be
 the worst -- that is, the most inaccurate -- social statistic ever.
 Full text:
 http://chronicle.com/free/v47/i34/34b00701.htm

Here is the progression, culminating in 35 trillion children
being gunned down in 1995, far beyond the population of the world
since its inception, as Best points out in the original
article.  In the article he describes tracking down the original
basis for the statistic.  At some point, doubling _since_ 1950
got translated into doubling every year since 1950.

Year# Children Gunned Down
1950   1
1951   2
1952   4
1953   8
1954  16
1955  32
1956  64
1957 128
1958 256
1959 512
1960   1,024
1961   2,048
1962   4,096
1963   8,192
1964  16,384
1965  32,768
1966  65,536
1967 131,072
1968 262,144
1969 524,288
1970   1,048,576
1971   2,097,152
1972   4,194,304
1973   8,388,608
1974  16,777,216
1975  33,554,432
1976  67,108,864
1977 134,217,728
1978 268,435,456
1979 536,870,912
1980   1,073,741,824
1981   2,147,483,648
1982   4,294,967,296
1983   8,589,934,592
1984  17,179,869,184
1985  34,359,738,368
1986  68,719,476,736
1987 137,438,953,472
1988 274,877,906,944
1989 549,755,813,888
1990   1,099,511,627,776
1991   2,199,023,255,552
1992   4,398,046,511,104
1993   8,796,093,022,208
1994  17,592,186,044,416
1995  35,184,372,088,832

Best wishes
Jim


James M. Clark  (204) 786-9757
Department of Psychology(204) 774-4134 Fax
University of Winnipeg  4L05D
Winnipeg, Manitoba  R3B 2E9 [EMAIL PROTECTED]
CANADA  http://www.uwinnipeg.ca/~clark




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Re: Combinometrics

2001-05-04 Thread Herman Rubin

In article 9ctkri$fjvug$[EMAIL PROTECTED],
Neville X. Elliven [EMAIL PROTECTED] wrote:
David Heiser wrote:

We seem to have a lot of recent questions involving combinations,
and probabilities of combinations.
I am puzzled.
Are these concepts no longer taught as a fundamental starting point in stat?

I haven't seen a Combinatorics course in a college class 
schedule in nearly twenty years, but combinations and their 
probabilities are still taught in Statistics courses 
[perhaps not with as much emphasis as previously].

Combinatorics used to be a standard topic in high school
algebra.  It is USED in probability calculations, which
are USED in statistical calculations, but it is not either
probability or statistics, no more than addition is.

In fact, it is overdone; students have no problems with
understanding equally likely, but have major problems 
with probability when this is not the case.  I also doubt
whether learning to compute answers gives any insight 
into the concepts, except for those with good research
potential, and even there it tends to confuse.
-- 
This address is for information only.  I do not claim that these views
are those of the Statistics Department or of Purdue University.
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399
[EMAIL PROTECTED] Phone: (765)494-6054   FAX: (765)494-0558


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Re: Analysis of a time series of categorical data

2001-05-04 Thread Rich Ulrich

On 3 May 2001 09:46:12 -0700, [EMAIL PROTECTED] (R. Mark Sharp; Ext.
476) wrote:

 If there is a better venue for this question, please advise me.

 - an epidemiology mailing list?
[ snip, much detail ] 
  Time point 1Time point 2Time point 3Time point 4  Hosts
  Inf  Not-InfInf  Not-InfInf  Not-InfInf  Not-Inf  Tested
 
 G1-S11  14   11  4   11 1   13 2   57
 G1-S27   8   12  3   14 2   15 8   69
 G1-S31  246 18815915   95
 
 G2-S43  12   12  4   10 4   14 2   61
 G2-S55  105  68 7   1114   57
 G2-S62  26   12 12   1116   1412  105
 
 The questions are how can group 1 (G1) be compare to group 2 (G2) and 
 how can subgroups be compared. I maintain that the heterogeneity 
 within each group does not prevent pooling of the subgroup data 
 within each group, because the groupings were made a priori based on 
 genetic similarity.

Mostly, heterogeneity prevents pooling.  
What's an average supposed to mean?

Only if the Ns represent naturally-occurring proportions, 
and so does your hypothesis, then you MIGHT want to
analyze the numbers that way.

How much do you know about the speed of expected onset,
and offset of the disease?  If this were real, It looks to me like you
would want special software.  Or special evaluation of a likelihood 
function.  

I can put the hypothesis in simple  ANOVA terms, comparing species
(S).  Then, the within-Variability of G1 and G2 -- which is big --
would be used to test the difference Between:  according to some
parameter.   Would that be an estimate of maximum number afflicted?

-- 
Rich Ulrich, [EMAIL PROTECTED]
http://www.pitt.edu/~wpilib/index.html


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Inference by Bootstrapping

2001-05-04 Thread Michael Robbins

I am fooling around with a paper that talks about how to do inferences, like
constructing confidence intervals, with the bootstrap method for inference...
because the assumption of i.i.d erros is reasonable... also... it is unlikely
that the cumulative distribution functions of our estimators are approximately
normal.

He also says ... we have to ensure that the residual errors are not correlated.
If the errors exhibit some correlation, then a transformation of the residuals
is in order.

S-PLUS has functions for this, but MATLAB does not.  Can anyone provide an
m-file, snippet, reference or discussion?

He references:

Efron (1982) The Jacknife, the Bootstap and Other Resampling Plans,
Philadelphia: Society for Industrial Applied Mathematics.

Seber and WIld (1989) Nonlinear Regression, New York, John Wley  sons

Shao and Tu (1995) The Jacknife and Boootstrap, New York, Springer

Michael Robbins, CFA
Director, Debt Capital Markets
CIBC World Markets Corp., Canadian Imperial Bank of Commerce
New York, NY   USA
[EMAIL PROTECTED] , [EMAIL PROTECTED]


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Re: Q: Arithmetic, Harmonic, Geometric, etc., Means

2001-05-04 Thread Robert J. MacG. Dawson



Stanley110 wrote:
 
 Ladies and Gentlemen,
 
 What is the physical significance or meaning regarding a manufacturing process
 whose output over an extended period of time has the same value for the
 arithmetic, geometric and harmonic mean of a property, its purity,  for
 example? ...  Or if any two are same and the third is different?

If any two are the same, the significance is that the output is
CONSTANT. For instance, for the arithmetic and geometric means:

(A) if n=2, AM = GM = x_1 = x_2.

Proof: sqrt(x_1 x_2) = (x_1 + x_2)/2
  =   x_1 x_2 = x_1^2/4 + x_1 x_2/2 + x_2^2/4
  =0= x_1^2/4 - x_1 x_2/2 + x_2^2/4
  = (x_1 - x_2)^2
  =   x_1 = x_2

(B) if n is a power of 2, by induction all the x_i are equal.

(C) even if n isn't a power of 2 a bit of algebra shows that
the same result holds (forgive me for omitting the details 
but it's late in the day and I have to get home to my family.)

Similar results hold for the other pairs of means, left as an
exercise (quite a pleasant one) for the curious.

If any of the data differ, there are inequalities (proved as above)
that show that the AM  GM  HM in all cases.

Analogous results hold for distributions.

-Robert Dawson


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No Subject

2001-05-04 Thread Carl Huberty



 Why do articles appear in print when 
study methods, analyses, results, and conclusions are somewhat faulty? 
[This may be considered as a follow-up to an earlier edstat interchange.] 
My first, and perhaps overly critical, response is that the editorial 
practices are faulty. I don't find Dennis Roberts' "reasons" in his 27 Apr 
message too satisfying. I regularly have students write critiques of 
articles in their respective areas of study. And I discover many, many, 
... errors in reporting. I often ask myself, WHY? I can think of two 
reasons: 1) journal editors can not or do not send manuscripts to reviewers with 
statistical analysis expertise; and 2) manuscript originators do not regularly 
seek methodologists as co-authors. Which is more prevalent?
 For whatever it is worth 
...

Carl Huberty


Re: Orthogonality of Designs for Experiments

2001-05-04 Thread Bob Wheeler

Since other respondents have given the official
answer which is an oversimplification that has
become dogma, and is too often offered up without
adequate explanation.  For the most part the
desire for absolute orthogonality comes from the
pre-computer era when it was difficult to design
and analyze non-orthogonal experiments. 

Experiments have many purposes, two of which are:
(1) to predict a response, and (2) to investigate
the effect of a factor. For prediction (1) there
is no need for orthogonality at all, however the
designs that produce the most information for a
given sample size tend to orthogonality, and
indeed in the limit are orthogonal. For (2), the
aim is to test a hypothesis about a factor, and
the correlation of the statistic used with other
statistics in the model is of minor importance:
all tests statistics for effects in a given
experiment are dependent (orthogonal or not) --
they involve the same error estimate; however, as
in (1) those designs that produce the most
powerful tests tend to orthogonality. 

If you use a design constructed to achieve some
respectable measure of efficiency, then you will
have no problem in the analysis unless you insist
on doing the calculations by hand.

Jeff wrote:
 
 Hello,
 
 Would like to ask the design of experiment gurus to help me with the
 following questions:
 
 1. why designs for experiments should be orthogonal ?
 
 2. which problems may I encounter if I use non-orthogonal design ?
 
 Thank you in advance.
 
 -- Jeff
 

-- 
Bob Wheeler --- (Reply to: [EMAIL PROTECTED])
ECHIP, Inc.


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Re:

2001-05-04 Thread Robert J. MacG. Dawson



 Carl Huberty wrote:
 
  Why do articles appear in print when study methods, analyses,
 results, and conclusions are somewhat faulty?... I can think of two
 reasons: 1) journal editors can not or do not send manuscripts to
 reviewers with statistical analysis expertise; and 2) manuscript
 originators do not regularly seek methodologists as co-authors.  Which
 is more prevalent?

I would say that both are more or less necessary conditions
for the appearance of a statistically illiterate paper. Neither is
sufficient. Any difference in prevalence would be hard to spot,
as the affected papers would be (in case 1\2) well-written but as 
pearls cast before swine; and (in case 2\1) sometimes well-written
despite the lack of consultation, and sometimes rejected.  1 1/2 of
these cases are hard to spot!

-Robert Dawson


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Re: Orthogonality of Designs for Experiments

2001-05-04 Thread Francois Bergeret

This is a multi-part message in MIME format.
--DBD3C05A63C0BFD0F8B0E075
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

hello,

Orthogonality is very important because it is an insurance that the
estimation of the effect of a factor is not dependant or the other
factors. For example, with orthogonality, you will have the same
estimation for factor A if you keep or remove factor B of the model. In
other words, your factor A is not depending of the other factors, so you
are more confident in the estimation.

Of course, you can analyze with no orthogonality, that is what we do
when analyzing databases. But one of the goal of Designs for Experiments
is to achieve orthogonality. Some Designs for Experiments are not
orthogonal but are as close as possible to orthogonality. They are
called D-optimal designs and can be used when you have a lot of levels
for each factor, so standard design do not work.

FR.

Jeff wrote:

 Hello,

 Would like to ask the design of experiment gurus to help me with the
 following questions:

 1. why designs for experiments should be orthogonal ?

 2. which problems may I encounter if I use non-orthogonal design ?

 Thank you in advance.

 -- Jeff

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Re: Please help

2001-05-04 Thread Donald Burrill

I rather think the problem is not adequately defined;  but that may 
merely reflect the fact that it's a homework problem, and homework 
problems often require highly simplifying assumptions in order to be 
addressed at all.  See comments below.

On Fri, 4 May 2001, Adil Abubakar wrote:

 My name is Adil Abubakar and i am a student and seek help.  snip
   if anyone can help, please respond to [EMAIL PROTECTED]
 
 Person A did research on a total of 4500 people and got the following
 results:

 Q. 1.  How many hours do you spend on the web?
 0-7 8-15  15+
 18% 48%   34%

 Q. 2.  Do you read a privacy policy before signing on to a web site?
 
  1=Strongly Agree 2=Agree 3=Neutral 4=disagree 5=strongly disagree 
 9%  17% 20%   32%22% 

If this were a research situation, or intended to reflect practical 
realities, there would also be information about the relationship between 
the answers to Q. 1 and the answers to Q. 2.  This information might be 
in the form of a two-way table of relative frequencies, or (with suitable 
simplifying assumptions on the variables represented by Q.1 and Q.2) as a 
ccorrelation coefficient.  Without _some_ information about the joint 
distribution, I do not see how one can hope to address the questions 
posed below.
 
 Another person asked the same questions of 100 people and got the same 
 results in % terms.  Can it be shown via CI that the result is
 consistent with the expectations created by the previous survey?

If the % results were indeed the same (so that all differences in 
corresponding %s were zero), it would not be necessary to use a CI (by 
which I presume you mean confidence interval) to show consistency. 
(HOWEVER, even identical % results do not imply consistency, unless at 
the same time the joint distribution were ALSO identical;  and you do 
not report information on this point.)

OTOH, if the results were merely similar but not identical, you would 
want some means of assessing the strength of evidence that resides in the 
empirical differences.  That in turn depends on the assumptions you're 
willing to make about the two variables:  do you insist on treating the 
responses as (ordered) categories, or would you be willing, at least pro 
tempore, to assign (e.g.) codes 1, 2, 3 to the responses to Q. 1, use the 
codes 1, 2, 3, 4, 5 supplied for Q. 2, and treat those values as though 
they represented approximately equal intervals?

 Also can it be argued that the subjects have been subjected to the
 questions before?

Not sure what you mean by this question.  If you know that the Ss have 
indeed been asked these questions previously (are they perhaps a subset 
of the original 4500?), no arguing is needed;  although what this would 
imply about the results is unclear.  If you mean, do the identical (or at 
least consistent) results imply that the Ss must have encountered these 
same questions previously, I do not see how that can be argued, at least 
not without more information than you've so far provided.  Perhaps more 
to the point, why would such an argument be of interest?

 Can it be asserted with statistical significance, that if the survey 
 is repeated on at least 100 people the result will [be] in the same 
 proximity of the above survey??

No.  I suggest you look closely at the definition of statistical 
significance:  the term is quite incompatible with the assertion you 
propose.  (If you don't see that, you might bring a focussed version of 
the question back to the list.  If you do see that, you may still have 
some question that is more or less in the same ball-park as the question 
you've asked here, and you may wish to bring the revised question to our 
attention.)

  any help ... will be appreciated.  Just need the different 
 methodologies. 

Yes;  but for which questions, exactly?
-- DFB.
 
 Donald F. Burrill [EMAIL PROTECTED]
 348 Hyde Hall, Plymouth State College,  [EMAIL PROTECTED]
 MSC #29, Plymouth, NH 03264 603-535-2597
 184 Nashua Road, Bedford, NH 03110  603-472-3742  



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Re: Orthogonality of Designs for Experiments

2001-05-04 Thread Donald Burrill

Short answers below;  which may or may not adequately address the lurking 
questions you had in mind.

On Fri, 4 May 2001, Jeff wrote:

 Would like to ask [for] help with the following questions:
 
 1. why designs for experiments should be orthogonal ?

So that results for each factor, and each interaction between factors, 
will be mutually independent.

 2. which problems may I encounter if I use non-orthogonal design ?

Same kinds of problems you encounter in the general multiple regression 
situation:  apparent size of effect of any predictor (or factor) will 
depend on the presence or absence of other predictors in the model, and 
also on the sequence in which the several predictors (factors and their 
interactions) are considered in the statistical model.
-- DFB.
 
 Donald F. Burrill [EMAIL PROTECTED]
 348 Hyde Hall, Plymouth State College,  [EMAIL PROTECTED]
 MSC #29, Plymouth, NH 03264 603-535-2597
 184 Nashua Road, Bedford, NH 03110  603-472-3742  



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Re: errors in journal articles

2001-05-04 Thread Thom Baguley

Warren Sarle wrote:

It reminds me of the recent headline in The Sunday Times (a leading
UK newspaper) that taxes had tripled under the present UK
government. As a bonus, the tax level when the government took
power, and reported in the article as part of the argument, was
something around 37% of GDP (the measure used throughout the article).

Thom


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Re: Estimating priors for Bayesian analysis

2001-05-04 Thread Duncan Murdoch

On 4 May 2001 04:11:23 -0700, [EMAIL PROTECTED] (Will Hopkins)
wrote:

For example, I might believe that the individual's true score is 70 units, 
and that the likely range is +/- 10 units.  So what describes 
likely?  90%, 95%, 99%...?  Do Bayesians have any validated way to work 
that out?  If they don't, then the whole Bayesian edifice might just come 
crashing down.  I put this to a Bayesian who has been helping me, but I 
have received no reply from him since I sent the message, so I suspect the 
worst.

It's hard to get the value very accurately, but the appropriate way is
to look at betting behaviour.  If you're claiming a 50% belief that
the value is between 60 and 80, then you should be indifferent to
accepting a bet at even odds of the value being inside or outside that
interval.  For other levels, it would be a bet with different odds:
e.g. you'd be willing to offer or accept 9 to 1 odds that it is in
your 90% interval.

Of course, there are other psychological things affecting the decision
to accept or reject such a bet (can I afford to lose?  Is winning
worth the trouble of thinking about it?  Do I think gambling is
immoral?  etc.), but the idea of indifference to each alternative is
the key idea.

Duncan Murdoch


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Re: Estimating methods in SEM

2001-05-04 Thread Herman Rubin

In article [EMAIL PROTECTED],
Kai Arzheimer  [EMAIL PROTECTED] wrote:
[EMAIL PROTECTED] (Rodney Carr) writes:



 The problem I am having is that I'm not sure what estimating method
 to use. EQS implements a number of different methods (Maximum
 Likelihood, Least Squares, GLS, etc). Unfortunately they give quite
 different results. Actually, LS gives fit indices that are fairly
 high, but none of the others do (so I'd like to use the LS method!).
 But I can't find any references that explain which method should be
 used. Please, do you have any ideas for where I might look for
 advice?

I did not notice the earlier article.  The question is what
is wanted, and why.

If one wants to come up with estimates of quantities based
on current values of other quantities, least squares and
related methods are quite appropriate.  If one wants to
understand what is happening structurally, least squares
is likely to give excessively high fits.

A VERY old example is that of estimating the consumption
function, C = \alpha + \beta * Y + error, Y being income. 
Now if one wants to come up with an estimate of this year's 
consumption from this year's income under unchanged 
conditions, least squares is fine.  But if one wants to
estimate the effect of a government making grants to people,
the structural value of \beta, not the regression value of
the LS coefficient \gamma, is what is wanted.


-- 
This address is for information only.  I do not claim that these views
are those of the Statistics Department or of Purdue University.
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399
[EMAIL PROTECTED] Phone: (765)494-6054   FAX: (765)494-0558


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Re: Orthogonality of Designs for Experiments

2001-05-04 Thread Jerry Dallal

Herman Rubin wrote:
 
 In article [EMAIL PROTECTED],
 Jeff [EMAIL PROTECTED] wrote:
 Hello,
 
 Would like to ask the design of experiment gurus to help me with the
 following questions:
 
 1. why designs for experiments should be orthogonal ?
 
 The computations get easier.

Also, the interpretation is usually more straightforward.
 
 2. which problems may I encounter if I use non-orthogonal design ?
 
 The nice simple ANOVA procedures are no longer valid.
 This does not mean that nothing can be done.

You may also encounter software that analyzes the data improperly!


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Re:

2001-05-04 Thread dennis roberts

At 09:44 AM 5/4/01 -0700, Carl Huberty wrote:
  Why do articles appear in print when study methods, analyses, 
 results, and conclusions are somewhat faulty?  [This may be considered as 
 a follow-up to an earlier edstat interchange.]  My first, and perhaps 
 overly critical, response  is that the editorial practices are faulty.  I 
 don't find Dennis Roberts' reasons in his 27 Apr message too satisfying.

i was not satisfied with my own list either but, these are reasons why 
screw ups do occur

  I regularly have students write critiques of articles in their 
 respective areas of study.  And I discover many, many, ... errors in 
 reporting.  I often ask myself, WHY?  I can think of two reasons: 1) 
 journal editors can not or do not send manuscripts to reviewers with 
 statistical analysis expertise;

unfortunately ... an editor has to beg sometimes to get reviewers and, 
sometimes ... beggars can't be choosers ... this is the reality of journal 
article submission reviewing ...
in addition ... a paper about say ... topic A ... has both content and 
methods ... and, you cannot always just find a person with skills in both 
... so, what are you to do? you have to get 2/3 people to AGREE to review a 
paper ... and, we know that these are not all in tune to the same things 
... thus, one might focus on methods/data ... another might focus on 
content theme ...

and 2) manuscript originators do not regularly seek methodologists as 
co-authors.

well, put yourself in the place of an untenured faculty member ... trying 
to get HIS/HER name as a sole author on sufficient stuff ... try to do it 
without a co-author ... you get more P and T points



  Which is more prevalent?
  For whatever it is worth ...


let's put all of this in the proper perspective ... there is just FAR too 
much emphasis on getting papers submitted and published (especially in the 
social sciences ... we are NOT medicine where miraculous breakthroughs DO 
happen) ... the editorial load is too great for the resources at hand (free 
... to boot!) ... so much of the stuff we do in the sake of scholarship is 
really  on the fringe of quality and usefulness ... but, we put more 
and more pressure on faculty to be part of the game

when will we wise up? we need LESS stuff done, but what's done should be of 
better quality over longer periods of time ... and of greater potential 
import ...

if we pick up say most of the good journals in our field ... and honestly 
read papers and ask ourselves ... does this really matter? is this really 
important?

if we are honest ... i would bet at least 50%-75% ... would be rated NO

but, it goes on your VITA ... guess that is what counts, right?


Carl Huberty

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dennis roberts, penn state university
educational psychology, 8148632401
http://roberts.ed.psu.edu/users/droberts/drober~1.htm



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Q: Arithmetic, Harmonic, Geometric, etc., Means

2001-05-04 Thread Stanley110

Ladies and Gentlemen,

What is the physical significance or meaning regarding a manufacturing process
whose output over an extended period of time has the same value for the 
arithmetic, geometric and harmonic mean of a property, its purity,  for
example?

What is the physical significance or meaning if the different means are not the
same?

Or if any two are same and the third is different?

Or if the different means agree for one property associated with the
manufacturing process and not another?

And can you direct me to literature or texts that address this subject?

Please reply to this newsgroup and to me at [EMAIL PROTECTED].

Thank you.

Stan Alekman


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Re: Combinometrics

2001-05-04 Thread Neville X. Elliven

David Heiser wrote:

We seem to have a lot of recent questions involving combinations,
and probabilities of combinations.
I am puzzled.
Are these concepts no longer taught as a fundamental starting point in stat?

I haven't seen a Combinatorics course in a college class 
schedule in nearly twenty years, but combinations and their 
probabilities are still taught in Statistics courses 
[perhaps not with as much emphasis as previously].


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