[Q : Test bivariate normal distribution?]
Dear Members fo News Group, I always appreciate that I could have received your help. As I know, I can apply Kolmogorov-Smirnov goodness-of-fit test to univariate sample. But, I don't know which method can be applied to multivariate samples, especially, when I got the samples assumed to be bivariate normal distributions. Please answer me . Thanks in advances. With my best regards, D.W. Ryu * Sent from RemarQ http://www.remarq.com The Internet's Discussion Network * The fastest and easiest way to search and participate in Usenet - Free!
Fellowship
FELLOWSHIPS IN REHABILITATION OUTCOMES RESEARCH. The UMDNJ/New Jersey Medical School, Department of Physical Medicine and Rehabilitation, and the Kessler Medical Rehabilitation Research Education Corp., announce a 1-2 year advanced research training program for professionals interested in objective and subjective outcomes experienced by persons with physical or neurological disabilities and factors that affect these outcomes. Medical rehabilitation outcomes research encompasses research on prognosis, measurement of function and health, treatment guidelines, outcomes management strategies, disability economics, and issues of health policy. Controlled research on the effectiveness and costs of interventions is stressed. Statistical and methodological skills are stressed in our program (without excluding qualitative investigations, which are necessary to explore certain topics.) The training program emphasizes the actual conduct of research, including writing fundable research proposals and publications. Fellows improve their research skills and knowledge of clinical rehabilitation during the program. The training program is based on an individualized Research and Training Plans written by each Fellow in collaboration with a primary mentor and secondary mentors. Mentors may be chosen from among many researchers throughout New Jersey, with special strength in neuropsychology, physiatry, PT, general outcomes methodology, traumatic brain injury, spinal cord injury, and other neurological disabilities. Both pre-doctoral (dissertation level) and post-doctoral positions are currently available. For substantive information, contact: Mark Johnston, PhD, (973) 243-6810, Project Director, [EMAIL PROTECTED] For application forms and instructions, contact: Heidi Castillo at (973) 243-6971, [EMAIL PROTECTED], or -- Scott R. Millis, PhD, ABPP Kessler Medical Rehabilitation Research Education Corp 1199 Pleasant Valley Way West Orange, New Jersey 07052 Tel: 973.243.6976 Fax: 973.243.6990 Emails: [EMAIL PROTECTED] [EMAIL PROTECTED]
Student Awards for STATISTICS AND HEALTH CONFERENCE
The Biostatistics Research Group of the University of Alberta is is pleased to announce that there will be several travel supplements awarded to students presenting at the Statistics in Health Conference in Edmonton, June 11-13, 2000. These student awards are funded thru the Institute of Health Economics, Alberta, the Biostatistics Section of the Statistical Society of Canada, the Biometrics Section of the American Statistical Association All students who present contributed papers are eligible to apply. Please note the deadline of February 1, 2000 for submission of abstracts to Statistics and Health conference http://www.stat.ualberta.ca/~brg/conf.html Some limitations apply. The award amount will be determined on an individual basis to a maximum of CD$500 per student. Interested students are asked to apply before April 15, 2000. The details of the terms of the awards will be posted in the above web site shortly. === K.C. Carriere Associate Professor of Statistics Department of Mathematical Sciences University of Alberta (tel)780-492-4230 Edmonton, AB T6G 2G1(fax)780-492-6826 Home: http://www.math.ualberta.ca/~kcarrier/kcarrier.html Visit: http://www.stat.ualberta.ca/~brg ===
statistical event definition?
i gather that a collection of events which is analyzed with statistics must have sufficient similarity (between each event) for the analysis to be accurate/precise. how similar is sufficient? can anyone recommend refs (preferably books) that discuss this issue, and provide guidelines for assuring sufficient similarity? does this consideration affect the appropriate choice of model? thanks in advance for sharing your wisdom experience. -- Any resemblance of any of the above opinions to anybody's official position is completely coincidental. Muriel Strand, P.E. Air Resources Engineer CA Air Resources Board 2020 L Street Sacramento, CA 59814 916-324-9661 916-327-8524 (fax) www.arb.ca.gov
Re: FACTOR ANALYSIS
If these factors were length measured in feet and in yards, would it make sense to have both in the same model. No If these factors were measure of ability like IQ, IQ test 1 and IQ test 2, then the question depends on how the two test are related. If they are highly correlated, drop one. If they measure different things then they should be included, if significant. If they overlap, look at your hypothesis and make a judgment based on the results. In article 864hr0$805$[EMAIL PROTECTED], "haytham siala" [EMAIL PROTECTED] wrote: Hi, I have a question related to factor analysis. If a questionnaire item was found to load significantly on more than one factor and let us assume that each factor represents a potential measurement scale for a particular construct, should I retain the same item for both factors (scales) i.e should that same item be included in the two measurement scales? Or should I take the highest loading of the item as the decisive solution to which factor it should belong? Cheers. Sent via Deja.com http://www.deja.com/ Before you buy.
Interrater reliability
Stat folks, I have an interrater reliability dilemma. We are examining a 3-item scale (each item scored 1 to 5) used to rate compliance behavior of patients. Two separate raters have used the scale to rate patients' behavior, and we now want to calculate the interrater agreement for the scale. Two problems: 1) The majority of patients are compliant, and receive either a 4 or 5 for each of the three items from both of the raters. While this is high agreement, values for ICC are very low due to the limited range of scores. Are there any indexes that would reflect the high agreement of the raters under these conditions? Perhaps something that accounts for the full range of the scale (1 to 5)? 2) The dataset contains a total of about 100 observations, but there are multiple observations on the same patients at different times, probably about 5 to 6 observations per patient. Does this repeated assessment need to be accounted for in the interrater agreement, or can each observation be treated as independent for the purpose of interrater agreement? Any suggestions or references addressing this problem would be appreciated. Thanks. Allen Cornelius
FACTOR ANALYSIS 2
When I perform a factor analysis on the items of a questionnaire should I include items that make up the Dependent Variables (DVs) as well as the Independent Variables (IVs) in the analysis or should I perform two separate factor analysis, one on the items making up the Dependent Variables and another on the items making up the Independent Variables.
FACTOR ANALYSIS
When I perform a factor analysis on the items of a questionnaire should I include items that make up the Dependent Variables (DVs) as well as the Independent Variables (IVs) in the analysis or should I perform two separate factor analysis, one on the items making up the Dependent Variables and another on the items making up the Independent Variables.
RE: Interrater reliability
Allen, You might refer to this paper. Burry-Stock, J. A., Shaw, D. G., Laurie, C., Chissom, B. S. (1996). Rater agreement indexes for performance assessment. Educational Psychological Measurement, 56, 251-262. Peter Chen -Original Message- From: Allen E Cornelius [SMTP:[EMAIL PROTECTED]] Sent: Wednesday, January 19, 2000 11:22 AM To: [EMAIL PROTECTED] Subject:Interrater reliability Stat folks, I have an interrater reliability dilemma. We are examining a 3-item scale (each item scored 1 to 5) used to rate compliance behavior of patients. Two separate raters have used the scale to rate patients' behavior, and we now want to calculate the interrater agreement for the scale. Two problems: 1) The majority of patients are compliant, and receive either a 4 or 5 for each of the three items from both of the raters. While this is high agreement, values for ICC are very low due to the limited range of scores. Are there any indexes that would reflect the high agreement of the raters under these conditions? Perhaps something that accounts for the full range of the scale (1 to 5)? 2) The dataset contains a total of about 100 observations, but there are multiple observations on the same patients at different times, probably about 5 to 6 observations per patient. Does this repeated assessment need to be accounted for in the interrater agreement, or can each observation be treated as independent for the purpose of interrater agreement? Any suggestions or references addressing this problem would be appreciated. Thanks. Allen Cornelius
Factor Analysis 3
Hi, I am sorry that I am sending a lot of questions related to this subject and here is another question: If some dissimilar iets load on a common factor (the factor does not seem to make sense since it consists of some related and some completely unrrelated items), should I ignore that factor or should I delete the unrrelated items from the factor analysis? Thanks in advance.
Sample Size for an Audit
We are going to do a quality system audit (like ISO 9000). How do I choose the sample size for a particular group of people? Let's say that there are 20 supervisors and I will audit their knowledge of SPC, how many should I choose for the audit? Sent via Deja.com http://www.deja.com/ Before you buy.
Re: Skewed Data Problem
On 19 Jan 2000 11:18:34 -0800, [EMAIL PROTECTED] (steinberg) wrote: snip ... . Most of the responses are zeros and ones. Square root and log transforms have very little effect on the right skew. (I added 1 to each score and took the log to avoid zeros.) The regression (output below) shows such a small R-squared that there would appear to be no meaningful association, although the - see the topics about ZERO in my stats-FAQ. "zero vs other" is one likely comparison. If most of the 'other' is 1, then "one vs other" might be useful, or the three-way comparison, "zero vs one vs other" -- Does this give an ordered set of values/scores for any of the other variables? -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html
Re: statistical event definition?
Well, we wouldn't try to analyze apples and autos in the same data set. :-) On the other hand, the similarity is sort of like what one requires for an efficient tabular data base. Whatever the sample space of events is, it should consist of events that we can think about together comfortably. If it takes a paragraph to describe each event, statistical methods aren't likely to be useful. We need to be able to code the data into compact data sets like measurements on a sample of objects, or a series of measurements on a single object. Sorry, I don't know of any formal criteria. Usually this is only discussed when somebody violates some statistician's common sense. Then it may be discussed in a rather combative atmosphere but privately, rather than publicly. Muriel Strand wrote: i gather that a collection of events which is analyzed with statistics must have sufficient similarity (between each event) for the analysis to be accurate/precise. how similar is sufficient? can anyone recommend refs (preferably books) that discuss this issue, and provide guidelines for assuring sufficient similarity? does this consideration affect the appropriate choice of model? thanks in advance for sharing your wisdom experience. -- Any resemblance of any of the above opinions to anybody's official position is completely coincidental. Muriel Strand, P.E. Air Resources Engineer CA Air Resources Board 2020 L Street Sacramento, CA 59814 916-324-9661 916-327-8524 (fax) www.arb.ca.gov
Re: Sample Size for an Audit
In any situation of this sort, the amount of data you need is related to the amount of variation you expect to find in the data... and is also related to "how close do you want your answer to be to the truth" and also with what probablity do you want to be that close to the truth. By truth I mean "true average response" or the population average. Statistical sampling theory is usually founded on taking a small sample from a large (infinite) population so that the sample does not "disturb" the population. If the sample size is a significant fraction of the entire population (as it will be in this instance, with only 20 people in the population), then a correction is needed to the usual formula for determining the correct sample size. I don't have that formula/correction at hand, but if you want it (or want a little paper I wrote on this) let me know at [EMAIL PROTECTED] If you want the paper, I'll need a fax number to send it to... it is not digitized. If the response you are measuring is a "pass/fail" response, that makes life easier because we can estimate the standard deviation quickly and painlessly. When all is said and done, with a population of only 20, the sample will need to be a large fraction of the population. Perhaps as many as 10 or 12. Charlie H. In article 86536f$j77$[EMAIL PROTECTED], [EMAIL PROTECTED] wrote: We are going to do a quality system audit (like ISO 9000). How do I choose the sample size for a particular group of people? Let's say that there are 20 supervisors and I will audit their knowledge of SPC, how many should I choose for the audit? Sent via Deja.com http://www.deja.com/ Before you buy. Sent via Deja.com http://www.deja.com/ Before you buy.
