Re: Question on Conditional PDF

Chia C Chong [EMAIL PROTECTED] wrote in message a5d38d$63e$[EMAIL PROTECTED]">news:a5d38d$63e$[EMAIL PROTECTED]... Glen [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Do you want to make any assumptions about the form of the conditional, or the joint, or

Re: detecting outliers in NON normal data ?

Voltolini wrote: Hi, I would like to know if methods for detecting outliers using interquartil ranges are indicated for data with NON normal distribution. The software Statistica presents this method: data point value UBV + o.c.*(UBV - LBV) data point value LBV - o.c.*(UBV - LBV)

Re: Cauchy PDF + Parameter Estimate

Herman Rubin wrote: In article a5daqb$72k$[EMAIL PROTECTED], Chia C Chong [EMAIL PROTECTED] wrote: Hi! Does anyone come across some Matlab code to estimate the parameters for the Cauchy PDF?? Or some other sources about the method to estimate their parameters?? What is so difficult

Re: What is an outlier ?

Voltolini wrote: Hi, My doubt isan outlier can be a LOW data value in the sample (and not just the highest) ? Several text boks dont make this clear !!! What makes an outlier an outlier is your model. If your model accounts for all the observations, you can't really call any of

Re: Question on CDF

Henry [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Fri, 22 Feb 2002 08:55:42 +1100, Glen Barnett [EMAIL PROTECTED] wrote: Bob [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... A straight line CDF woul

Re: Question on CDF

Henry [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... I was trying to suggest that he meant the slope of the CDF was the height of the PDF. Oh, okay. Yes, that would be correct, but it shouldn't be called probability! Glen

Re: Question on CDF

Bob [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... [EMAIL PROTECTED] (Linda) wrote in message news:[EMAIL PROTECTED]... Hi! If I plot CDF of a sample data and this CDF looks like a straight line cross through 0. What does this implies?? Normally, CDF

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

Linda [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Hi! I have some experimental data collected and can be grouped into 2 variables, X and Y. One is the dependent variable (Y) and the other is an independent variable (X). What test shall I made to check

Re: Chi-square chart in Excel

Ronny Richardson wrote: Can anyone tell me how to produce a chart of the chi-square distribution in Excel? (I know how to find chi-square values but not how to turn those into a chart of the chi-square curve.) Ronny Richardson

Re: Normalization procedures

Niko Tiliopoulos wrote: Hello everybody, Has anybody heard of the Bell-Doksum test? IIRC it's like a Wilcoxon 2-sample test, except that the ranks are transformed to normal scores. If that's the right test, it has ARE 1 vs the t-test (it has good power for small deviations), but as you

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Ian Buckner [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Glen Barnett [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Ian Buckner wrote: We generate pairs of properly distributed Gaussian variables at

Re: Numerical recipes in statistics ???

Charles Metz [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... The Truth wrote: I suppose I should have been more clear with my question. What I essentially require is a textbook which presents algorithms like Monte Carlo, Principal Component Analysis,

Re: Numerical recipes in statistics ???

The Truth [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Glen Barnett [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED]... The Truth wrote: Are there any Numerical Recipes like textbook on statistics and probability ? Just wondering..

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Herman Rubin [EMAIL PROTECTED] wrote in message a4u99j$[EMAIL PROTECTED]">news:a4u99j$[EMAIL PROTECTED]... In article [EMAIL PROTECTED], Radford Neal [EMAIL PROTECTED] wrote: Box-Muller does not work for real time requirements. This isn't true, of course. A real time application is one

Re: Numerical recipes in statistics ???

The Truth wrote: Are there any Numerical Recipes like textbook on statistics and probability ? Just wondering.. What do you mean, a book with algorithms for statistics and probability or a handbook/cookbook list of techniques with some basic explanation? Glen

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Ian Buckner wrote: We generate pairs of properly distributed Gaussian variables at down to 10nsec intervals, essential in the application. Speed can be an issue, particularly in real time situations. Generated on what? (On a fast enough machine, even clunky old Box-Muller can probably give

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Alan Miller [EMAIL PROTECTED] wrote in message OC2b8.28457$[EMAIL PROTECTED]">news:OC2b8.28457$[EMAIL PROTECTED]... First - the reference to George's paper on the ziggurat, and the code: The Journal of Statistical Software (2000) at: http://www.jstatsoft.org/v05/i08 That I already have,

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Bob Wheeler [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Marsaglia's ziggurat and MCW1019 generators are available in the R package SuppDists. The gcc compiler was used. Thanks Bob. Glen =

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

George Marsaglia [EMAIL PROTECTED] wrote in message 0l7b8.42092$[EMAIL PROTECTED]">news:0l7b8.42092$[EMAIL PROTECTED]... (3-year old) Timings, in nanoseconds, using Microsoft Visual C++ and gcc under DOS on a 400MHz PC. Comparisons are with methods by Leva and by Ahrens-Dieter, both said

Re: Which is faster? ziggurat or Monty Python (or maybe something else?)

Art Kendall [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... I tend to be more concerned with the apparent randomness of the results than with the speed of the algorithm. This will be mainly a function of the randomness of the uniform generator. If we assume the

Re: test differences between proportions

Rich Ulrich wrote: On Mon, 11 Feb 2002 13:56:46 +0100, nikolov [EMAIL PROTECTED] wrote: hello, i want to test the difference between two proportions. The problem is that some elements of these proportions are dependent (i can not isolate them). That is, the t-statistics does not

Re: Ansari-Bradley dispersion test.

Rich Ulrich [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Sat, 09 Feb 2002 16:59:34 GMT, Johannes Fichtinger [EMAIL PROTECTED] wrote: Dear NG! I have been searching for a description of the Ansari-Bradley dispersion test up to now for analysing a

Re: Method for determining gaussian distribution

Jennifer Golbeck wrote: i hope someone can help me with this. i have finished a computer science study that examines swarming behavior. my claim is that the swarming algorithm that i use produces a gaussian distribution - on a grid, the frequency that each area is visited is recorded.

Re: area under the curve

Dennis Roberts wrote: unless you had a table comparable to the z table for area under the normal distribution ... for EACH different level of skewness ... an exact answer is not possible in a way that would be explainable Even if you specify level of skewness, an exact answer is still not

Re: How to test f(X , Y)=f(X)f(Y)

Linda [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... I have 1000 observations of 2 RVs from an experiments. X is the independent variable and Y is the dependent variable. How do I perform the test whether the following statement is true or not??

Re: Unique Root Test - Statistics

Shakti Sankhla [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Hi All: This is basically not a SAS problem but I believe that many of the list members could help. I am looking for information on Statistical topic called Unique Root Test. Do you mean unit

Re: 95% CI for a sum

Scheltema, Karen wrote: I have 2 independent samples and the standard errors and n's associated with each of them. If a and b are constants, what is the formula for the 95% confidence interval for (a(Xbar1)+b(xbar2))? Are the sample sizes big enough that you'd be prepared to use the CLT?

Re: Buy Book on Probability and statistical inference

Chia C Chong [EMAIL PROTECTED] wrote in message a1phfd$36e$[EMAIL PROTECTED]">news:a1phfd$36e$[EMAIL PROTECTED]... Hi! I wish to get a book in Probability and statistical inference . I wish to get some advices first..Any good suggestion?? (i) What do you know already? (ii) What do you need

Re: Modelling Problem

Alexander Hener wrote: I have a modelling problem where any help would be appreciated. Assume that I want to model a fraction, where the nominator is a sum of, Do you mean numerator? say, four continous random variables. I am thinking of using some parameter-additive distribution there,

Re: Which one fit better??

Chia C Chong [EMAIL PROTECTED] wrote in message a1bpk5$62b$[EMAIL PROTECTED]">news:a1bpk5$62b$[EMAIL PROTECTED]... Glen [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Chia C Chong [EMAIL PROTECTED] wrote in message news:a0n001$b7v$[EMAIL PROTECTED]... I

Re: Question on 2-D joint distribution...

Chia C Chong [EMAIL PROTECTED] wrote in message a145qk$qfq$[EMAIL PROTECTED]">news:a145qk$qfq$[EMAIL PROTECTED]... Hi! I have a series of observations of 2 random variables (say X and Y) from my measurement data. These 2 RVs are not independent and hence f(X,Y) ~= f(X)f(Y). Hence, I can't

Re: Standardizing evaluation scores

Stan Brown wrote: But is it worth it? Don't the easy graders and :tough graders pretty much cancel each other out anyway? Not if some students only get hard graders and some only get easy graders. If all students got all graders an equal amount of time it probably won't matter at all. Glen

Re: Basics

colsul wrote: Does anyone know of a website that deals with basic statistic formulae and/or business math? Also, I am looking for a text book that could give me a grounding in the basics of statistics, stat. analysis and business maths. I need to cram so I have some idea for a job interview

Re: 10 envelopes, 10 persons

Stan Brown wrote: Problem posed me by a student: ten persons (A through J) and ten envelopes containing cards marked with letters A through J. (Each letter is in one and only one envelope.) The random variable x is the number of people who get the right envelope when the envelopes are

Re: Testing for joint probability between 2 variables

Chia C Chong [EMAIL PROTECTED] wrote in message news:9rn4vc$8v2$[EMAIL PROTECTED]... Glen [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Chia C Chong [EMAIL PROTECTED] wrote in message news:9rjs94$lht$[EMAIL PROTECTED]... I have 2 variables and would

Re: Testing for joint probability between 2 variables

Glen Barnett [EMAIL PROTECTED] wrote in message 9rndu1$gqq$[EMAIL PROTECTED]">news:9rndu1$gqq$[EMAIL PROTECTED]... I'd probably suggest not trying to group the data and do a chi-squared measure of association (you're throwing away the ordering, where most of the information will be)

Re: Comparing percent correct to correct by chance

Donald Burrill [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Sun, 28 Oct 2001, Melady Preece wrote: Hi. I want to compare the percentage of correct identifications (taste test) to the percentage that would be correct by chance 50%? (only two items

Re: Transformation function for proportions

Rich Ulrich [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Wed, 17 Oct 2001 15:50:35 +0200, Tobias Richter [EMAIL PROTECTED] wrote: We have collected variables that represent proportions (i. e., the proportion of sentences in a number of texts that

Re: Transformation function for proportions

Rich Strauss [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED]... However, the arcsin transformation is for proportions (with fixed It's also designed for stabilising variance rather than specifically inducing symmetry. Does it actually produce symmetry as well? denominator), not

Re: Are parametric assumptions importat ?

Yes [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Glenn Barnett wrote: One n in Glen. OK, I see what you were getting at - but I still disagree, if it is understood that we are talking about large samples. Your original comment that I was replying to was:

Re: Are parametric assumptions importat ?

Robert J. MacG. Dawson wrote: Voltolini wrote: Hi, I am Biologist preparing a class on experiments in ecology including a short and simple text about how to use and to choose the most commom statistical tests (chi-square, t tests, ANOVA, correlation and regression). I am planning

Re: Mean and Standard Deviation

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 happen with data

Re: semi-studentized residual

James Ankeny wrote: Hello, I have a question regarding the so-called semi-studentized residual, which is of the form (e_i)* = ( e_i - 0 ) / sqrt(MSE). Here, e_i is the ith residual, 0 is the mean of the residuals, and sqrt(MSE) means the square root of MSE. Now, if I understand

Re: E as a % of a standard deviation

John Jackson [EMAIL PROTECTED] wrote in message MGns7.49824$[EMAIL PROTECTED]">news:MGns7.49824$[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

Re: Difference between BOX and JENKIN TRANSFER FUNCTION model and

Marg wrote: Greetings.. Can anyone suggest me what are the differences between Box and Jenkin Transfer function model and multiple regression model? Are there any good tutorials or freewares that deal with the Box and Jenkin Transfer function model? The basic difference is that the TF

Re: Normality in Factor Analysis

Robert Ehrlich [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Calculation of eigenvalues and eigenvalues requires no assumption. However evaluation of the results IMHO implicitly assumes at least a unimodal distribution and reasonably homogeneous variance for

Re: Help me, please!

Monica De Stefani [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... 2) Can Kendall discover nonlinear dependence? He used to be able to, but he died. (Look at how Kendall's tau is calculated. Notice that it is not affected by any monotonic increasing

Re: Combinometrics

David Heiser [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... 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

Re: A disarmingly simple conjecture

Giuseppe Andrea Paleologo wrote: I am dealing with a simple conjecture. Given two generic positive random variables, is it always true that the sum of the quantiles (for a given value p) is greater or equal than the quantile of the sum? In other words, let X, Y be positive random

Re: Homework Problem

Michael Scheltgen [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Suppose X1, X2, X3, and X4 have a multivariate Normal Dist'n with mean vector u, and Covariance matrix, sigma. (a) Suppose it is known that X3 = x3 and X4 = x4. What is: 1)The expected value

Re: Most Common Mistake In Statistical Inference

W. D. Allen Sr. [EMAIL PROTECTED] wrote in message nH9u6.6370$[EMAIL PROTECTED]">news:nH9u6.6370$[EMAIL PROTECTED]... A common mistake made in statistical inference is to assume every data set is normally distributed. This seems to be the rule rather than the exception, even among

Re: help with modelling

Debraj [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... hi, I have a set of data which indicates number of correct responses on a test (score) for 20 persons. I wanted to know if I can model the same mathematically based on certain factors, say Score =

Re: accuracy, median or mean

Paul Foran wrote: Is Accuracy measured as sample mean or sample median distance from true value You could define something called accuracy as either of these, or indeed as something else. Is there a particular context you're asking about? It may be that in some areas the term has an accepted

Re: Tests of Statistical Significance

Rich Ulrich [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Sorry, I am missing it - -- I couldn't quite work it out either. I often have that problem though. Glen = Instructions for joining

Re: ANOVA with dichotomous dependent variable

Gerhard Luecke wrote: Can anyone name some references where the problem of using a DICHOTOMOUS variable as a DEPENDENT variable in an ANOVA is discussed? Many thanks in advance, Gerhard Luecke I'd first try logistic regression. If all your variables are categorical, you can look at some

Re: Which book do you recommend?

[EMAIL PROTECTED] wrote: Comments, please, on the relative merits of the standard textbooks: Bickel Doksum Casella Berger Cox Hinkley Or is there some other book that you prefer? This question has been posted before, but nobody responded, so I'm asking again. Surely someone out

Re: question about binomial distribution

Thomas Souers [EMAIL PROTECTED] wrote in message 17920451.972429742277.JavaMail.imail@slippery">news:17920451.972429742277.JavaMail.imail@slippery... I have a question regarding basic statistics, and while it might seem foolish to some of you, I would greatly appreciate any help: Suppose a

Re: probability questions

[EMAIL PROTECTED] wrote: Two probability questions... If X has chi-square distribution with 5 degrees of freedom 1. what is the probability of X 3 2. what is the probability of X 3 given that X 1.1 Homework, right? Glen

Re: More probability

[EMAIL PROTECTED] wrote: A random variable, X, has the Uniform distribution f(x) = [0.4, 0 a x 2.5 otherwise 1. what is a 2. what is the probability 1 x 2 given that x .5 3. what is the median 4. what is c such that P(x c) = .05 More homework. Glen

Re: consistent statistic

Chuck Cleland wrote: Hello: If I understand the concept correctly, a consistent statistic is one whose value approaches the population value as the sample size increases. I am looking for examples of statistics that are _not_ consistent. The best examples would be statistics that are

Re: Skewness and Kurtosis Questions

- Original Message - From: David A. Heiser [EMAIL PROTECTED] To: [EMAIL PROTECTED]; Glen Barnett [EMAIL PROTECTED] Sent: Friday, September 01, 2000 1:13 PM Subject: Re: Skewness and Kurtosis Questions Barnett then goes on... Now, if I delete the two 150's on the end of data set

Re: Skewness and Kurtosis Questions

christopher.mecklin [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... And as far as using EXCEL's help menus as a stat reference, well EXCEL 2000 also claims the following about the two-sample t-test: "You can use t-tests to determine whether two sample means

Re: Skewness and Kurtosis Questions

Ronny Richardson [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... 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 You

Re: transforming ratios

Jeff E. Houlahan [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... A colleague is looking at the relative amounts of two different types of fatty acids (say, fatty acids A and B) that are incorporated in two different types of tissues. He is comparing the ratio

Re: t-test normality assumption

Bob Hayden wrote: In addition to the approximation involved in using the CLT, most (possibly all) practical situations require that you estimate the population standard deviation with the sample standard deviation in calculating a standard error for use in constructing a confidence interval

Re: summarizing p-values

[EMAIL PROTECTED] wrote in message 8mbhrh$fuk$[EMAIL PROTECTED]">news:8mbhrh$fuk$[EMAIL PROTECTED]... Hello from Germany, as a part of my dissertation in medicine, I have to summarize some results of clinical trials. My question: By summarizing the results (percentage differences of certain

Re: skewness Kurtosis

jagan mohan [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Repected Members, Coefficient of Skewness (beta-1) = (3rd moment)^2/ (2nd moment)^3 Coefficient of Kurtosis (beta-2) = (4th moment)/(2nd moment)^2. where do I get proofs for these two.Please let me

Re: Power Function Neagtive Intercept

Dr. N.S. Gandhi Prasad [EMAIL PROTECTED] wrote in message 013501bff62b$f871d6e0$[EMAIL PROTECTED]">news:013501bff62b$f871d6e0$[EMAIL PROTECTED]... I have fitted a power function Y = a (X1^b1)*(x2^b2)*(X3^b3) by transfroming Y as well as Xs in to LOGs and followed least Squares procedure.

Re: extrapolation

Veeral Patel [EMAIL PROTECTED] wrote in message news:397cfc9a$[EMAIL PROTECTED]... Hi, I have a set of data (25000 samples), i have plotted a histogram , the Wow! How many observations in each sample? Glen = Instructions

Re: contrasts for Kruskal Wallis

Richard M. Barton [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... Suppose I have 4 groups, and want to compare means. I do a one-way ANOVA using Bonferroni (my choice) contrasts to get at pairwise differences. Suppose I decide that I have non-normality

Re: Recommendation?

Michael Atherton [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... I will be applying for faculty positions in Education this year and I was wondering if any one can recommend departments where alternative views on education (i.e., non-constructivist) are

Re: Skewness: is 1 Normal? Says Who?

Donald Burrill [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... On Thu, 6 Jul 2000, John Nash wrote (to the AERA-D list): Many of us operate under the following assumption: For |skewness coefficient| 1, data is considered to be normally distributed.

Re: this list

Rich Ulrich wrote: [...] - I agree with that. - and here is something that I read today on another group, which is directly about the problem of protesting about posters who annoy you. Dealing with Chambers is easy - people like that infest most of usenet. If you have killfiles, *plonk*.

Re: Disadvantage of Non-parametric vs. Parametric Test

Frank E Harrell Jr wrote: Alex Yu wrote: Disadvantages of non-parametric tests: Losing precision: Edgington (1995) asserted that when more precise measurements are available, it is unwise to degrade the precision by transforming the measurements into ranked data.

Re: Disadvantage of Non-parametric vs. Parametric Test

Rich Ulrich wrote: - In my vocabulary, these days, "nonparametric" starts out with data being ranked, or otherwise being placed into categories -- it is the infinite parameters involved in that sort of non-reversible re-scoring which earns the label, nonparametric. (I am still trying to

Re: Disadvantage of Non-parametric vs. Parametric Test

Alex Yu wrote: Disadvantages of non-parametric tests: Losing precision: Edgington (1995) asserted that when more precise measurements are available, it is unwise to degrade the precision by transforming the measurements into ranked data. So this is an argument against rank-based

Re: Sample size and non-parametric test

boonlert wrote: Dear All Can I use a non-parametric test for a sample size less than 30 (central limit theorem) Sorry, but (i) what has the central limit theorem have to do with any of this? (ii) for that matter, what does a sample size of 30 really have to do with the central limit