SAS is the best package for Factor analysis in Windows
In my opinion SAS is the best computer package for Factor analysis in Windows. And for most other analyses too... = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: SAS is the best package for Factor analysis in Windows
On Thu, 06 Sep 2001 13:41:32 GMT, [EMAIL PROTECTED] (Andreas Karlsson) wrote: In my opinion SAS is the best computer package for Factor analysis in Windows. And for most other analyses too... testing... = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Simple Probability Proof Requested
In article [EMAIL PROTECTED], Sloppy Joe [EMAIL PROTECTED] wrote: Greetings - Suppose I have a method such as a fair 6-sided die. I roll the die 10 times and get the following trial history: 3-5-1-3-6-4-6-2-1-5 From what I can recall from probability, I cannot predict the next roll of the die based on the previous rolls. Each number on the die will have an equal probability of occuring on the 11th roll no matter what has occurred previously: 1/6. My question is this ... How can this be proven mathematically? Thanks for any help! This follows from independence. The usual, and in my opinion quite poor, definition of independence (skipping some steps) is the if one has k independent random variables, P(X_i \in E_i for all i) = \prod P(X_i \in E_i); this is enough to get the result you want. A better definition is that if one forms an even A from some of the variables, the conditional probability of A given any information about the rest of them is the same as the unconditional probability; this is the way it is used, anyhow. -- 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 = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Simple Probability Proof Requested
Sloppy Joe [EMAIL PROTECTED] wrote: Greetings - Suppose I have a method such as a fair 6-sided die. I roll the die 10 times and get the following trial history: 3-5-1-3-6-4-6-2-1-5 From what I can recall from probability, I cannot predict the next roll of the die based on the previous rolls. Each number on the die will have an equal probability of occuring on the 11th roll no matter what has occurred previously: 1/6. My question is this ... How can this be proven mathematically? It can't be. It's just the conventional definition of fair. There is no reason why a die cannot be weighted so that the probability of a certain number appearing on any roll is *not* 1/6; and there is no reason why a die cannot be constructed (say, using some cunning clockwork, or lead shot in a very viscous liquid) so that the probabilities for one roll depend on the rolls before it. Neither of these is ruled out by the observation described above (though they provide some evidence against the repeating die last described). Moreover, a die may have equal probability without independence, or independence without equal probability. Fairness is generally understood as implying both properties. (This may not quite correspond to the general meaning. If I say I have a weighted die in my pocket that only rolls one number. I bet you 5 to 1 that you cannot guess what it will roll! that is a fair bet - once! Moreover, it is a fair bet even if I do not tell you that the die is loaded, provided its faces only have conventional numbers of spots (1 through 6, though not necessarily one of each.)) -Robert Dawson = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
RE: Factor analysis - which package is best for Windows?
MVA comes with R base. However, it is a seperate library. Libraries that are not sent with base are available in Windows binaries on CRAN, but you do not have to worry about that for MVA. Type: library() and you will get a list of the available packages. To make MVA available (i.e. load it), type: library(mva) then you can ask for, for example: help (factanal) -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] Sent: Wednesday, September 05, 2001 5:42 PM To: [EMAIL PROTECTED] Subject: Re: Factor analysis - which package is best for Windows? [EMAIL PROTECTED] (Magill, Brett) wrote in message news:[EMAIL PROTECTED]... Also check out R, a GNU implementation of the S language, most prominently known through its use in S-Plus. R is a fully featured statisitical programming environment. In its MVA (Multivariate) package, it includes routines for factor analysis using maximum liklihood estimation with varimax and promax rotations. I have installed R1.3.0 on my Windows system and have noted that MVA is an add-on. The FAQ tells how to obtain these add-ons but only for UNIX. Is this add-on actually available for Windows? If so, how do I obtain it? Thanks, Peter = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: How estimate p to Bernoulli Trial?
Rafael, Is this homeworks? You're on the right track...you either need a separate guess for the probability of success or you need an estimate from a sample. Is there an even chance of turning right or left? Are you a classicist, a frequentist or a subjectivist? :) Warren [EMAIL PROTECTED] (RFerreira) wrote in message news:[EMAIL PROTECTED]... Hi, To a single Bernoulli Trial (one car leaving the park goes left or right)if I preview go to right and this happens trial out is success .But what p probability I can give to this? I imagine the correct way is tally the frequencies at ,eg, 10 cars go right and then do my only trial, with some p of shure. This is p is achieved After some number of Bernoulii trials to be used Before one or more future trials? Thank you in advance for any comments. Regards Rafael = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Definitions of Likert scale, Likert item, etc.
A recent question made me realize the extent of ambiguity in the use of Likert scale and related terms. I'd like to see things be more clear. Here are my thoughts (I don't claim they are correct; they're just a starting point for discussion). Concise responses are encouraged. If there are enough, I'll post a summary. 1. Likert scaling strictly refers to the scaling method developed by Likert in the 1930's. If refers entire process of scaling a set of many items (i.e., as an alternative to Thurstone scaling). One step of this is administering many items to individuals. Each item has integer-labeled rating levels. Likert used the method only for attitude measurement, and with response categories indicating levels of agreement to specific statements, like: I believe the work week should be reduced to 32 hours. 1. strongly disagree 2. mildly disagree 3. neither agree nor disagree 4. mildly agree 5. strongly agree 2. A Likert scale, strictly speaking, refers to a set of many such items. 3. I do not know if Likert also used a visual analog format such as: neither strongly mildly agree normildly strongly disagree disagree disagree agree agree 1 2 3 4 5 +-+--+--+-+ 4. It seems reasonable to refer to a single such item as a Likert item. However, many people seem to refer to a single item of this type as a Likert scale; that would seem to invite confusion, as Likert's original intent was to produce a scale compused of many such items. 5. Many researchers use such items outside the area of attitude measurement; it seems reasonable to refer to such items as Likert-type items, to distinguish them from strict Likert items as described above. If anyone has any definitive references that clarify this, I would greatly appreciate learning of them. John Uebersax, PhD (805) 384-7688 Thousand Oaks, California (805) 383-1726 (fax) email: [EMAIL PROTECTED] Agreement Stats: http://ourworld.compuserve.com/homepages/jsuebersax/agree.htm Latent Structure: http://ourworld.compuserve.com/homepages/jsuebersax Existential Psych: http://members.aol.com/spiritualpsych = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
RE: Definitions of Likert scale, Likert item, etc.
In general, as these things always seem to go, many folks call any item from a summated rating scale a Likert item. But, like the use of relationship instead of relation, it seems to be a difficult practice to stamp out. Paul R. Swank, Ph.D. Professor Developmental Pediatrics UT Houston Health Science Center -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of John Uebersax Sent: Thursday, September 06, 2001 12:44 PM To: [EMAIL PROTECTED] Subject: Definitions of Likert scale, Likert item, etc. A recent question made me realize the extent of ambiguity in the use of Likert scale and related terms. I'd like to see things be more clear. Here are my thoughts (I don't claim they are correct; they're just a starting point for discussion). Concise responses are encouraged. If there are enough, I'll post a summary. 1. Likert scaling strictly refers to the scaling method developed by Likert in the 1930's. If refers entire process of scaling a set of many items (i.e., as an alternative to Thurstone scaling). One step of this is administering many items to individuals. Each item has integer-labeled rating levels. Likert used the method only for attitude measurement, and with response categories indicating levels of agreement to specific statements, like: I believe the work week should be reduced to 32 hours. 1. strongly disagree 2. mildly disagree 3. neither agree nor disagree 4. mildly agree 5. strongly agree 2. A Likert scale, strictly speaking, refers to a set of many such items. 3. I do not know if Likert also used a visual analog format such as: neither strongly mildly agree normildly strongly disagree disagree disagree agree agree 1 2 3 4 5 +-+--+--+-+ 4. It seems reasonable to refer to a single such item as a Likert item. However, many people seem to refer to a single item of this type as a Likert scale; that would seem to invite confusion, as Likert's original intent was to produce a scale compused of many such items. 5. Many researchers use such items outside the area of attitude measurement; it seems reasonable to refer to such items as Likert-type items, to distinguish them from strict Likert items as described above. If anyone has any definitive references that clarify this, I would greatly appreciate learning of them. John Uebersax, PhD (805) 384-7688 Thousand Oaks, California (805) 383-1726 (fax) email: [EMAIL PROTECTED] Agreement Stats: http://ourworld.compuserve.com/homepages/jsuebersax/agree.htm Latent Structure: http://ourworld.compuserve.com/homepages/jsuebersax Existential Psych: http://members.aol.com/spiritualpsych = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Definitions of Likert scale, Likert item, etc.
again ... the best place to read about what rensis likert did ... is to read his work: a technique for the measurement of attitudes, archives of psychology, #140, New York, June 1932 to the best of my knowledge, this document is not online in any form (not that it should be) even though it is a sort of famous document (but, unread far too often) here are examples of each type of item that likert used in this work ... his dissertation under the guidance of gardner murphy likert used 3 different attitude scales ... each consisting of multiple items one was the internationalism scale, one was the negro scale, the final one was an imperialism scale below, i will give ONE example from each type of item used (not necessarily from each scale) QUESTION ASKED YES NO kind of response scale Do you favor the early entrance of the United States into the League of Nations? YES (4) ? (3)NO (2)#s = scale weights [THERE WERE 19 ITEMS LIKE THIS ACROSS THE 3 SCALES] QUESTION ASKED WITH VERBAL OPTIONS FOR RESPONSES How much military training should we have? (a) We need universal compulsory military training (1) (b) We need Citizens Military Training Camps and Reserve Officers Training Corps, but not universal military training (2) (c) We need some facilities for training reserve officers but not as much as at present (3) (d) We need only such military training as is required to maintain our regular army (4) (e) All military training should be abolished (5) [THERE WERE 8 ITEMS LIKE THIS (hard to make)ACROSS THE 3 SCALES] STATEMENT PRESENTS WITH TYPICAL LIKERT RESPONSE SCALE All men who have the opportunity should enlist in the Citizens Military Training Camps Strongly Approve (1) Approve (2) Undecided (3) Disapprove (4) Strongly Disapprove (5) [THERE WERE 31 ITEMS LIKE THIS ACROSS THE 3 SCALES] now, NO OTHER FORMS OF ITEMS WERE USED BY LIKERT IN THIS 1932 WORK ... for each attitude scale, a summed value was obtained ... At 10:44 AM 9/6/01 -0700, John Uebersax wrote: A recent question made me realize the extent of ambiguity in the use of Likert scale and related terms. I'd like to see things be more clear. Here are my thoughts (I don't claim they are correct; they're just a starting point for discussion). Concise responses are encouraged. If there are enough, I'll post a summary. _ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Definitions of Likert scale, Likert item, etc.
we do have a semantics problem with terms like this ... scale ... and confuse sometimes the actual physical paper and pencil instrument with the underlying continuum on which we are trying to place people so, even in likert's work ... he refers to THE attitude scales ... and then lists the items on each ... thus, it is easy to see an equating made between the collection of items ... nicely printed ... BEING the scale ... but really, the scale is not that ... one has to think about the SCORE value range ... that is possible ... when this physical thing (nicely printed collection of items) is administered to Ss ... thus ... for 10 typically response worded likert items with SA to SD ... the range of scores on the scale might be 10 to 50 ... of which any particular S might get any one of those values somewhere along the continuum but of course, scale is even deeper than that since, what we really have is a psychophysical problem ... that is, what is the functional relationship that links the physical scale ... 10 to 50 ... to the (assumed to exist) underlying psychological continuum ... PHYSICAL SCALE 10 (NEGATIVE) 50 (POSITIVE) PSYCHOLOGICAL CONTINUUM MOST NEGATIVE MOST POSITIVE problems like ... do equal distances along the physical scale ... equate to the same and equal distances along the psychological continuum? is there a linear relationship between these two? curvilinear? so, i think what we really mean by scale is this construct ... ie, the psychological continuum ... and a scale value would be where a S is along it ... but, about the best we can do to assess this is to see where the S is along the physical scale ... ie, where from 10 to 50 ... and use this as our PROXY measure ... BUT IN any case ... i think it is helpful NOT to call the actual instrument ... the paper and pencil collection of items ... THE scale ... _ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Definitions of Likert scale, Likert item, etc.
Rensis Likert was instrumental in founding the Institute for Social Research at the University of Michigan in the mid 1940s. He was truly a pioneer statistician and psychologist. He retired from Michigan in 1970 and passed away in 1981. Variants of his 1 to 5 or 1 to 7 scale are still found on many questionnaires in spite of the question about scaling, equal distances, etc. His studies on leadership and and production still hold interest. On 6 Sep 2001 14:48:44 -0700, [EMAIL PROTECTED] (Dennis Roberts) wrote: we do have a semantics problem with terms like this ... scale ... and confuse sometimes the actual physical paper and pencil instrument with the underlying continuum on which we are trying to place people so, even in likert's work ... he refers to THE attitude scales ... and then lists the items on each ... thus, it is easy to see an equating made between the collection of items ... nicely printed ... BEING the scale ... but really, the scale is not that ... one has to think about the SCORE value range ... that is possible ... when this physical thing (nicely printed collection of items) is administered to Ss ... thus ... for 10 typically response worded likert items with SA to SD ... the range of scores on the scale might be 10 to 50 ... of which any particular S might get any one of those values somewhere along the continuum but of course, scale is even deeper than that since, what we really have is a psychophysical problem ... that is, what is the functional relationship that links the physical scale ... 10 to 50 ... to the (assumed to exist) underlying psychological continuum ... PHYSICAL SCALE 10 (NEGATIVE) 50 (POSITIVE) PSYCHOLOGICAL CONTINUUM MOST NEGATIVE MOST POSITIVE problems like ... do equal distances along the physical scale ... equate to the same and equal distances along the psychological continuum? is there a linear relationship between these two? curvilinear? so, i think what we really mean by scale is this construct ... ie, the psychological continuum ... and a scale value would be where a S is along it ... but, about the best we can do to assess this is to see where the S is along the physical scale ... ie, where from 10 to 50 ... and use this as our PROXY measure ... BUT IN any case ... i think it is helpful NOT to call the actual instrument ... the paper and pencil collection of items ... THE scale ... _ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Definitions of Likert scale, Likert item, etc.
It's certainly true that there is a semantic problem, with people interpreting terms in different ways. (So what's new?) Having started life (so to speak) as a mathematician, a 'scale' is a characteristic of the variable being measured. The construct that a couple of people have referred to as a 'Likert scale' I would call a 'variable' (or possibly 'measure'). The range of possible values, and the way they are laid out (eg, for 0 to 100, hopefully 'interval' or even 'ratio') forms the scale for this variable. The common usage of 'Likert scale' to mean an ordinal scale, usually from 1 to 5, usually expressing level of agreement with a proposition fits this view of the terms. An individual item of this type defines a variable, and this variable has a Likert scale, in this sense of the term. The composite variable or measure (hopefully) has a reasonably numeric scale. Regards, Alan Dennis Roberts wrote: we do have a semantics problem with terms like this ... scale ... and confuse sometimes the actual physical paper and pencil instrument with the underlying continuum on which we are trying to place people so, even in likert's work ... he refers to THE attitude scales ... and then lists the items on each ... thus, it is easy to see an equating made between the collection of items ... nicely printed ... BEING the scale ... but really, the scale is not that ... one has to think about the SCORE value range ... that is possible ... when this physical thing (nicely printed collection of items) is administered to Ss ... thus ... for 10 typically response worded likert items with SA to SD ... the range of scores on the scale might be 10 to 50 ... of which any particular S might get any one of those values somewhere along the continuum but of course, scale is even deeper than that since, what we really have is a psychophysical problem ... that is, what is the functional relationship that links the physical scale ... 10 to 50 ... to the (assumed to exist) underlying psychological continuum ... PHYSICAL SCALE 10 (NEGATIVE) 50 (POSITIVE) PSYCHOLOGICAL CONTINUUM MOST NEGATIVE MOST POSITIVE problems like ... do equal distances along the physical scale ... equate to the same and equal distances along the psychological continuum? is there a linear relationship between these two? curvilinear? so, i think what we really mean by scale is this construct ... ie, the psychological continuum ... and a scale value would be where a S is along it ... but, about the best we can do to assess this is to see where the S is along the physical scale ... ie, where from 10 to 50 ... and use this as our PROXY measure ... BUT IN any case ... i think it is helpful NOT to call the actual instrument ... the paper and pencil collection of items ... THE scale ... _ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ = -- Alan McLean ([EMAIL PROTECTED]) Department of Econometrics and Business Statistics Monash University, Caulfield Campus, Melbourne Tel: +61 03 9903 2102Fax: +61 03 9903 2007 = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Definitions of Likert scale, Likert item, etc.
Alan McLean wrote: The composite variable or measure (hopefully) has a reasonably numeric scale. I don't think (in light of the Central Limit Theorem) that the problem is whether the composite's reasonably numeric. It is. The problem, when the data's given the usual ANOVic treatment, is what the heck the mean means. In some circumstances the only important thing is how many people strongly agree and the Laodiceans can be lumped with the naysayers. In other circumstances other interpretations apply. Taking the arithmetic mean of Likert data fudges this issue. -Robert Dawson = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: Factor analysis - which package is best for Windows?
I can't say whether it any good, let alone the best. But I have just seen the following on an archaeological post. UNESCO has released WinIDAMS 1.0 for 32-bit Windows operating system. WinIDAMS is a freeware software package for numerical information processing and statistical analysis. It provides a complete set of data manipulation and validation facilities and a wide range of classical and advanced statistical techniques, including interactive construction of multidimensional tables, graphical exploration of data and time series analysis. You can find more information at the following url: http://www.unesco.org/idams I have checked the URL. It does offer factor analysis. Richard Wright = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
