Revision control for SPSS source code
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Revision control for SPSS source code
 
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I've been looking at various options for revision control of SPSS source
code files. Anyone else have any experience with various tools like subversion or bazaar? Any recommendations for what works well in the SPSS environment? In our shop, there are only a handful of developers, generally working on separate projects. Thanks for any guidance or help you can provide. -Tim Graettinger ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: Revision control for SPSS source code
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The IBM SPSS Collaboration and Deployment
Services tool is designed to manage models, syntax, files, outputs etc
in a way that allows you also to kick off jobs, monitor results, handle
workflows etc. You can read about it here
http://www.spss.com/software/deployment/ There are many revision control systems around, each with its own strengths. A lot depends on how distributed you need the system to be. We use ClearCase internally, but that might well be overkill for your needs. Subversion, Mercurial, Bazaar, GIT, ... are all popular. HTH, Jon Peck Senior Software Engineer, IBM [hidden email] 312-651-3435 From: Tim Graettinger <[hidden email]> To: [hidden email] Date: 03/28/2011 09:57 AM Subject: [SPSSX-L] Revision control for SPSS source code Sent by: "SPSSX(r) Discussion" <[hidden email]> I've been looking at various options for revision control of SPSS source code files. Anyone else have any experience with various tools like subversion or bazaar? Any recommendations for what works well in the SPSS environment? In our shop, there are only a handful of developers, generally working on separate projects. Thanks for any guidance or help you can provide. -Tim Graettinger ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Strange behavior of VARIABLE LABELS in macro
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Hello to everybody: When I run this simple macro: ************************************************************************. DEFINE !separar_ie (evaluacion = !CHAREND('/') / codigo =!CHAREND('/')). DATASET COPY !evaluacion. DATASET ACTIVATE !evaluacion. FILTER OFF. USE ALL. SELECT IF (cod_eva = !codigo). EXECUTE. SORT CASES BY prioridad (A) codgeo (A) corre_med (A) cod_al (A). DELETE VARIABLES casos_ie_C_10 casos_ie_M_10 cen_pob region26 TO nombres. COMPUTE correlativo=$CASENUM. EXECUTE. ALTER TYPE correlativo (F6.0). VARIABLE LABELS cod_eva V001 correlativo V002 prioridad V003 codgeo V004 corre_med V005 cod_mod7 V006 anexo V007 nom_nino V008 ie V009 ubicacion V010 en_cl V011 texto1_C V012 en_m V013 texto1_M V014 se_ubica_C V015 nivel_C V016 texto2_C V017 se_ubica_M V018 nivel_M V019 texto2_M V020 p_g3_ie_C_10 V021 p_g2_ie_C_10 V022 p_g1_ie_C_10 V023 p_g3_ie_M_10 V024 p_g2_ie_M_10 V025 p_g1_ie_M_10 V026. SORT VARIABLES BY LABEL. SAVE OUTFILE=!QUOTE(!CONCAT('D:\Censo Alumnos 2010\Documentos\Reportes\Segundo\Padres\Reporte Padres 2do ',!evaluacion,'.sav')) /COMPRESSED. DATASET ACTIVATE Reporte_padres. !ENDDEFINE. !separar_ie evaluacion = MC / codigo = 2. ************************************************************************. I get an error message: Warning # 4463 in column 25. Text: V001 correlativo V002 prioridad V003 codgeo V004 corre_med V005 A label specified on the VAR LABELS command contains more than 256 characters. The label will be truncated to 256 characters. If I run the VARIABLE LABELS outside the macro, I don't get the error, and every variable gets its correct label. I can run the VARIABLE LABELS like this: VARIABLE LABELS cod_eva 'V001' correlativo 'V002' prioridad 'V003' codgeo 'V004'. inside the macro and works fine. I'm triying to understand why something like: VARIABLE LABELS cod_eva V001 correlativo V002 prioridad V003 codgeo V004. doesn't works inside the macro, Kindly Andrés Mg. Andrés Burga León Coordinador de Análisis e Informática Unidad de Medición de la Calidad Educativa Ministerio de Educación del Perú Calle El Comercio s/n (espalda del Museo de la Nación) Lima 41 Perú Teléfono 615-5840 |
Re: Strange behavior of VARIABLE LABELS in macro
Administrator
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My guess is you need to use !QUOTE, like this:
VARIABLE LABELS cod_eva !quote(V001) correlativo !quote(V002) prioridad !quote(V003) etc HTH.
--
Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." PLEASE NOTE THE FOLLOWING: 1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. 2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/). |
Re: Strange behavior of VARIABLE LABELS in macro
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In reply to this post by ANDRES ALBERTO BURGA LEON
I'm not a macro expert, but the first thing
I'd do is SET MPRINT ON before calling the macro to see what the generated
syntax is.
From: ANDRES ALBERTO BURGA LEON <[hidden email]> To: [hidden email] Date: 03/28/2011 12:12 PM Subject: Strange behavior of VARIABLE LABELS in macro Sent by: "SPSSX(r) Discussion" <[hidden email]> Hello to everybody: When I run this simple macro: ************************************************************************. DEFINE !separar_ie (evaluacion = !CHAREND('/') / codigo =!CHAREND('/')). DATASET COPY !evaluacion. DATASET ACTIVATE !evaluacion. FILTER OFF. USE ALL. SELECT IF (cod_eva = !codigo). EXECUTE. SORT CASES BY prioridad (A) codgeo (A) corre_med (A) cod_al (A). DELETE VARIABLES casos_ie_C_10 casos_ie_M_10 cen_pob region26 TO nombres. COMPUTE correlativo=$CASENUM. EXECUTE. ALTER TYPE correlativo (F6.0). VARIABLE LABELS cod_eva V001 correlativo V002 prioridad V003 codgeo V004 corre_med V005 cod_mod7 V006 anexo V007 nom_nino V008 ie V009 ubicacion V010 en_cl V011 texto1_C V012 en_m V013 texto1_M V014 se_ubica_C V015 nivel_C V016 texto2_C V017 se_ubica_M V018 nivel_M V019 texto2_M V020 p_g3_ie_C_10 V021 p_g2_ie_C_10 V022 p_g1_ie_C_10 V023 p_g3_ie_M_10 V024 p_g2_ie_M_10 V025 p_g1_ie_M_10 V026. SORT VARIABLES BY LABEL. SAVE OUTFILE=!QUOTE(!CONCAT('D:\Censo Alumnos 2010\Documentos\Reportes\Segundo\Padres\Reporte Padres 2do ',!evaluacion,'.sav')) /COMPRESSED. DATASET ACTIVATE Reporte_padres. !ENDDEFINE. !separar_ie evaluacion = MC / codigo = 2. ************************************************************************. I get an error message: Warning # 4463 in column 25. Text: V001 correlativo V002 prioridad V003 codgeo V004 corre_med V005 A label specified on the VAR LABELS command contains more than 256 characters. The label will be truncated to 256 characters. If I run the VARIABLE LABELS outside the macro, I don't get the error, and every variable gets its correct label. I can run the VARIABLE LABELS like this: VARIABLE LABELS cod_eva 'V001' correlativo 'V002' prioridad 'V003' codgeo 'V004'. inside the macro and works fine. I'm triying to understand why something like: VARIABLE LABELS cod_eva V001 correlativo V002 prioridad V003 codgeo V004. doesn't works inside the macro, Kindly Andrés Mg. Andrés Burga León Coordinador de Análisis e Informática Unidad de Medición de la Calidad Educativa Ministerio de Educación del Perú Calle El Comercio s/n (espalda del Museo de la Nación) Lima 41 Perú Teléfono 615-5840 |
Re: Strange behavior of VARIABLE LABELS in macro
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In reply to this post by ANDRES ALBERTO BURGA LEON
> Date: Mon, 28 Mar 2011 12:06:06 -0500
> From: [hidden email] > Subject: Strange behavior of VARIABLE LABELS in macro > To: [hidden email] > [snip] > > If I run the VARIABLE LABELS outside the macro, I don't get the error, > and every variable gets its correct label. > > I can run the VARIABLE LABELS like this: > > VARIABLE LABELS > cod_eva 'V001' > correlativo 'V002' > prioridad 'V003' > codgeo 'V004'. > > inside the macro and works fine. I'm triying to understand why > something like: > > VARIABLE LABELS > cod_eva V001 > correlativo V002 > prioridad V003 > codgeo V004. > > doesn't works inside the macro, The labels are in quotes in the first example, so SPSS knows where a label ends. If there was a separate "Variable Labels" line for each variable, and the label was followed by a period, you could even have labels with multiple words without quotes. Since the parser wraps lines together, it does not know that V002 is supposed to be the whole label for cod_eva. -- Rich Ulrich ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
exact versus asymptotic p-value under normal circumstances
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One more question...
I have the SPSS Exact Tests module, which allows one to compute an exact p-value for a chi-square test on any size table (not just 2x2). I was taught to use exact tests under certain circumstances, e.g. when the expected value in any cell falls below 5. My dataset is about 250, so usually that condition doesn't apply. However, I am still finding that the exact p-value differs significantly from the asymptotic p value...sometimes to the extent that they lead to different conclusions. I'm not sure whether I should rely on the exact p-value anytime it differs from the asymptotic one, or if I should stick with the asymptotic when the usual assumptions for chi-square are met. For example: On the crosstabs I just ran, X2=4.49, 3 degrees of freedom, asymptotic sig is showing up as .212, and exact sig as .028. All expected cell counts were greater than 5. If I didn't have the exact tests module, I would have just gone with the .212 and retained the null hypothesis. Now that I have exact, should I use it or not? Thanks for any advice, Bridgette ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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The exact test always "trumps" the asymptotic test; you should use the exact
test result. The rule of thumb about the expected value in any cell falling below 5 is just that - a rule of thumb - and no more. Exact tests are useful in situations of sparseness, skewness, extreme imbalance, and small sample sizes. It is difficult to state before the fact when you would get a different result. Tony Babinec [hidden email] -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bridgette Portman Sent: Monday, March 28, 2011 3:34 PM To: [hidden email] Subject: exact versus asymptotic p-value under normal circumstances One more question... I have the SPSS Exact Tests module, which allows one to compute an exact p-value for a chi-square test on any size table (not just 2x2). I was taught to use exact tests under certain circumstances, e.g. when the expected value in any cell falls below 5. My dataset is about 250, so usually that condition doesn't apply. However, I am still finding that the exact p-value differs significantly from the asymptotic p value...sometimes to the extent that they lead to different conclusions. I'm not sure whether I should rely on the exact p-value anytime it differs from the asymptotic one, or if I should stick with the asymptotic when the usual assumptions for chi-square are met. For example: On the crosstabs I just ran, X2=4.49, 3 degrees of freedom, asymptotic sig is showing up as .212, and exact sig as .028. All expected cell counts were greater than 5. If I didn't have the exact tests module, I would have just gone with the .212 and retained the null hypothesis. Now that I have exact, should I use it or not? Thanks for any advice, Bridgette ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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Administrator
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Hi Tony. I disagree about exact tests always trumping asymptotic tests. Take the 2x2 table, for example. Fisher's exact test was designed for the situation where both the row and column totals are fixed in advance (Model I, as Barnard 1947 called it). If that is not the case, FET is known to be too conservative. When the marginal totals are not fixed in advance, the N-1 chi-square test (an asymptotic test) is a much better choice, IMO.
For more details about this particular example, take a look at Ian Campbell's website, and his article in Statistics in Medicine. http://www.iancampbell.co.uk/twobytwo/background.htm The same thing applies to certain confidence intervals. E.g., exact (Clopper-Pearson) confidence intervals for binomial proportions are considered by many to be inferior to other methods. Here's a note from the GraphPad site that makes this argument: http://www.graphpad.com/articles/CIofProportion.htm Cheers, Bruce
--
Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." PLEASE NOTE THE FOLLOWING: 1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. 2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/). |
Re: exact versus asymptotic p-value under normal circumstances
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In my previous post, I am touting the Cytel Software historical "party
line." Mehta, Patel, and colleagues made a lot of progress by working in the fixed marginals case. They make some arguments that try to justify that approach even which the sampling model/research design by which the table is thought to arise is not the fixed totals situation. They have done some work to move beyond this in a couple areas. One is exact power and sample size for comparing two binomials by Barnard's unconditional exact test for difference and ratio. Yes, I am aware of work that shows that Fisher's Exact Test for the 2x2 can be improved on; think that Agresti talks about it. I believe that Hirji, cited on the Campbell page, was as Cytel for a time. He subsequently published his own book; I don't own it. My sense is that there is no justification for the Cochran-Yates rule of thumb, which is what I was responding to in the original post that as I read it was not about the 2x2 case. Tony Babinec [hidden email] -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bruce Weaver Sent: Monday, March 28, 2011 5:01 PM To: [hidden email] Subject: Re: exact versus asymptotic p-value under normal circumstances Hi Tony. I disagree about exact tests always trumping asymptotic tests. Take the 2x2 table, for example. Fisher's exact test was designed for the situation where both the row and column totals are fixed in advance (Model I, as Barnard 1947 called it). If that is not the case, FET is known to be too conservative. When the marginal totals are not fixed in advance, the N-1 chi-square test (an asymptotic test) is a much better choice, IMO. For more details about this particular example, take a look at Ian Campbell's website, and his article in Statistics in Medicine. http://www.iancampbell.co.uk/twobytwo/background.htm The same thing applies to certain confidence intervals. E.g., exact (Clopper-Pearson) confidence intervals for binomial proportions are considered by many to be inferior to other methods. Here's a note from the GraphPad site that makes this argument: http://www.graphpad.com/articles/CIofProportion.htm Cheers, Bruce ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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In reply to this post by Bridgette Portman
> Date: Mon, 28 Mar 2011 13:34:29 -0700
> From: [hidden email] > Subject: exact versus asymptotic p-value under normal circumstances > To: [hidden email] > > One more question... > > I have the SPSS Exact Tests module, which allows one to compute an exact > p-value for a chi-square test on any size table (not just 2x2). I was > taught to use exact tests under certain circumstances, e.g. when the > expected value in any cell falls below 5. My dataset is about 250, so > usually that condition doesn't apply. However, I am still finding that the > exact p-value differs significantly from the asymptotic p > value...sometimes to the extent that they lead to different conclusions. > I'm not sure whether I should rely on the exact p-value anytime it differs > from the asymptotic one, or if I should stick with the asymptotic when the > usual assumptions for chi-square are met. The difference in results is *not* due to the failure of the Pearson approximation -- That one "fails" when there are tiny Expectations, and the symptom is that the resulting test is too big. You have the opposite result - your Pearson test is less significant. I expect that if you look at the other "approximate" test, the Likelihood test, you will also see a difference from the Pearson. For a table larger than 2x2, the two tests effectively "weight" differently the observed deviations from Expected. The Pearson will give a tinier p-value when there tends to have a single extreme value, and it will give a larger p- value when deviations are shown in several cells. Agresti (Categorical Data Analysis, 1990) mentions the family of "power divergence" statistics introduced by Cressie and Read (1984). These two tests are special cases of the family. - The so-called "exact" tests offer more than one choice for weighting, if I am not recalling a different package. Several choices certainly do exist. Anyway, the difference in weighting is almost surely the source of your observation. That's a little detail about "exact" which is too often overlooked. > > For example: On the crosstabs I just ran, X2=4.49, 3 degrees of freedom, > asymptotic sig is showing up as .212, and exact sig as .028. All expected > cell counts were greater than 5. > > If I didn't have the exact tests module, I would have just gone with the > .212 and retained the null hypothesis. Now that I have exact, should I use > it or not? The most important thing is that you don't cherry-pick among results. That is, you should use the same version of testing across all your results. I prefer to see a chi-squared tests, because the X^2's give me another basis for comparing various results within a study. (And a bit of redundancy, to help avoid typographical errors, etc.) The next important thing might be -- Use whatever is standard in the journals where you may publish. -- Rich Ulrich ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: Revision control for SPSS source code
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In reply to this post by Tim Graettinger
We use Subversion, because it's a tried and a true program, and it's also free. I don't know any other version control programs though. Subsversion has a lot of functionality; in fact more than I need. I also like the file diff feature.
Albert-Jan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ From: Tim Graettinger <[hidden email]> To: [hidden email] Sent: Mon, March 28, 2011 5:51:18 PM Subject: [SPSSX-L] Revision control for SPSS source code I've been looking at various options for revision control of SPSS source code files. Anyone else have any experience with various tools like subversion or bazaar? Any recommendations for what works well in the SPSS environment? In our shop, there are only a handful of developers, generally working on separate projects. Thanks for any guidance or help you can provide. -Tim Graettinger ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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In reply to this post by Bridgette Portman
El 28/03/2011 22:34, Bridgette Portman wrote:
> For example: On the crosstabs I just ran, X2=4.49, 3 degrees of freedom, > asymptotic sig is showing up as .212, and exact sig as .028. All expected > cell counts were greater than 5. Hi Bridgette: In my experience, exact p values are usually higher than their asymptotic counterparts,(and both are very similar when sample sizes are big). Therefore, I find strange the great discrepancy between the exact & asymptotic p values that you report. Is there any chance that by mistake you annotated the "Point probability" instead of the "Exact sig. (2-tailed)"? Best regards, Marta GG ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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Administrator
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In reply to this post by Bridgette Portman
Hi Bridgette. A couple things.
1. Can you post your table of observed counts? 2. For tables larger than 2x2, the chi-square approximation is pretty good as long as no more than 20% of expected counts are < 5, and none are < 1. The reference I've always used for point 2 is Yates, Moore & McCabe (1999, p. 734). But I just noticed that Agresti says the same thing (in the book Rich U referred to earlier), and he cites Cochran (1954). Cheers, Bruce
--
Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." PLEASE NOTE THE FOLLOWING: 1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. 2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/). |
Re: exact versus asymptotic p-value under normal circumstances
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In reply to this post by Marta Garcia-Granero
Hi Marta,
No, I'm definitely reading the exact p-value. I find this strange too -- I've spent the last couple days searching the internet for an answer to this and I can't figure it out. My exact p-values on any table larger than 2x2 are almost invariably smaller than my asymptotic ones. I'm no longer trusting the exact values, which leaves me unsure how to analyze the results from tables larger than 2x2 when cell counts are low. Has anyone used the SPSS exact tests module too? I am really stuck at this point. Bridgette > El 28/03/2011 22:34, Bridgette Portman wrote: > >> For example: On the crosstabs I just ran, X2=4.49, 3 degrees of >> freedom, >> asymptotic sig is showing up as .212, and exact sig as .028. All >> expected >> cell counts were greater than 5. > > Hi Bridgette: > > In my experience, exact p values are usually higher than their > asymptotic counterparts,(and both are very similar when sample sizes are > big). Therefore, I find strange the great discrepancy between the exact > & asymptotic p values that you report. Is there any chance that by > mistake you annotated the "Point probability" instead of the "Exact sig. > (2-tailed)"? > > Best regards, > Marta GG > > ===================== > To manage your subscription to SPSSX-L, send a message to > [hidden email] (not to SPSSX-L), with no body text except the > command. To leave the list, send the command > SIGNOFF SPSSX-L > For a list of commands to manage subscriptions, send the command > INFO REFCARD > > ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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Could you share a table with us. We need to compare results with other exact packages.
Dr. Paul R. Swank, Professor and Director of Research Children's Learning Institute University of Texas Health Science Center-Houston -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bridgette Portman Sent: Wednesday, March 30, 2011 6:44 PM To: [hidden email] Subject: Re: exact versus asymptotic p-value under normal circumstances Hi Marta, No, I'm definitely reading the exact p-value. I find this strange too -- I've spent the last couple days searching the internet for an answer to this and I can't figure it out. My exact p-values on any table larger than 2x2 are almost invariably smaller than my asymptotic ones. I'm no longer trusting the exact values, which leaves me unsure how to analyze the results from tables larger than 2x2 when cell counts are low. Has anyone used the SPSS exact tests module too? I am really stuck at this point. Bridgette > El 28/03/2011 22:34, Bridgette Portman wrote: > >> For example: On the crosstabs I just ran, X2=4.49, 3 degrees of >> freedom, >> asymptotic sig is showing up as .212, and exact sig as .028. All >> expected >> cell counts were greater than 5. > > Hi Bridgette: > > In my experience, exact p values are usually higher than their > asymptotic counterparts,(and both are very similar when sample sizes are > big). Therefore, I find strange the great discrepancy between the exact > & asymptotic p values that you report. Is there any chance that by > mistake you annotated the "Point probability" instead of the "Exact sig. > (2-tailed)"? > > Best regards, > Marta GG > > ===================== > To manage your subscription to SPSSX-L, send a message to > [hidden email] (not to SPSSX-L), with no body text except the > command. To leave the list, send the command > SIGNOFF SPSSX-L > For a list of commands to manage subscriptions, send the command > INFO REFCARD > > ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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Administrator
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I just discovered that Bridgette sent some output to the Hotmail account I use for posting to this list. (Bridgette, as it says in my sig file, I only use that account for mailing to this list, and check it only occasionally. If you want to correspond off-list, please use the everyday e-mail address given in my sig file.)
So, here is syntax to generate her table, and the tests of interest. Notice that the results I get do not match the ones she sent me. * Bridgette's data. data list list / row col kount (3f5.0). begin data 1 1 11 1 2 16 2 1 14 2 2 35 3 1 8 3 2 21 4 1 23 4 2 27 end data. var lab row "Death personality" col "Age group" . val lab row 1 "Cruel" 2 "Gentle" 3 "Impassive" 4 "Other/variable" / col 1 "Under 40" 2 "40 plus" . weight by kount . crosstabs row by col / stat = chisqr. * For those who have the Exact Tests module . CROSSTABS /TABLES=row BY col / stat = chisqr /METHOD=EXACT TIMER(5). * My results (using v18 with all patches under Windoze XP Professional): * Pearson: Asymptotic p = .213, exact p = .216 . * Likelihood ratio: Asymptotic p = .212, exact p = .219 . * Output Bridgette sent me: * Pearson: Asymptotic p = .213, exact p = .028 . * Likelihood ratio: Asymptotic p = .212, exact p = .047 . Bridgette, what version of SPSS are you using? Have all the available patches been applied? Also, regarding Age Group, why group? Do you have the actual ages? Cheers, Bruce
--
Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." PLEASE NOTE THE FOLLOWING: 1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. 2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/). |
Re: exact versus asymptotic p-value under normal circumstances
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Bruce,
Good work. Your reported results make sense. A quick run in unpatched version 19 shows results that do not agree and could be suspect. Those are the numbers that are being reported by Bridgette. I don't have StatXact on the machine where I'm at, but would think that its results would agree with the ones your report. So, this appears to be a problem -- known or unknown -- in version 19. Tony Babinec [hidden email] -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bruce Weaver Sent: Thursday, March 31, 2011 10:08 AM To: [hidden email] Subject: Re: exact versus asymptotic p-value under normal circumstances I just discovered that Bridgette sent some output to the Hotmail account I use for posting to this list. (Bridgette, as it says in my sig file, I only use that account for mailing to this list, and check it only occasionally. If you want to correspond off-list, please use the everyday e-mail address given in my sig file.) So, here is syntax to generate her table, and the tests of interest. Notice that the results I get do not match the ones she sent me. * Bridgette's data. data list list / row col kount (3f5.0). begin data 1 1 11 1 2 16 2 1 14 2 2 35 3 1 8 3 2 21 4 1 23 4 2 27 end data. var lab row "Death personality" col "Age group" . val lab row 1 "Cruel" 2 "Gentle" 3 "Impassive" 4 "Other/variable" / col 1 "Under 40" 2 "40 plus" . weight by kount . crosstabs row by col / stat = chisqr. * For those who have the Exact Tests module . CROSSTABS /TABLES=row BY col / stat = chisqr /METHOD=EXACT TIMER(5). * My results (using v18 with all patches under Windoze XP Professional): * Pearson: Asymptotic p = .213, exact p = .216 . * Likelihood ratio: Asymptotic p = .212, exact p = .219 . * Output Bridgette sent me: * Pearson: Asymptotic p = .213, exact p = .028 . * Likelihood ratio: Asymptotic p = .212, exact p = .047 . Bridgette, what version of SPSS are you using? Have all the available patches been applied? Also, regarding Age Group, why group? Do you have the actual ages? Cheers, Bruce ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Re: exact versus asymptotic p-value under normal circumstances
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Administrator
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Sorry Tony, but I'm about to throw a spanner into the works. One of my colleagues just started using v19, and it is not yet patched, so I asked him to run the code. He got the same p-values I did for the two exact tests.
Exact p = .216 for Pearson Exact p = .219 for Likelihood ratio Cheers, Bruce
--
Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." PLEASE NOTE THE FOLLOWING: 1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. 2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/). |
Re: exact versus asymptotic p-value under normal circumstances
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I am running Windows 7 64-bit. I see that Dave Matheson posted something
on this. Tony Babinec [hidden email] -----Original Message----- From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bruce Weaver Sent: Thursday, March 31, 2011 1:34 PM To: [hidden email] Subject: Re: exact versus asymptotic p-value under normal circumstances Sorry Tony, but I'm about to throw a spanner into the works. One of my colleagues just started using v19, and it is not yet patched, so I asked him to run the code. He got the same p-values I did for the two exact tests. Exact p = .216 for Pearson Exact p = .219 for Likelihood ratio Cheers, Bruce Anthony Babinec wrote: > > Bruce, > Good work. Your reported results make sense. A quick run in unpatched > version 19 shows results that do not agree and could be suspect. Those > are the numbers that are being reported by Bridgette. I don't have > StatXact on the machine where I'm at, but would think that its results > would agree with the ones your report. So, this appears to be a > problem -- known or unknown > -- in > version 19. > > > Tony Babinec > [hidden email] > > -----Original Message----- > From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf > Of Bruce Weaver > Sent: Thursday, March 31, 2011 10:08 AM > To: [hidden email] > Subject: Re: exact versus asymptotic p-value under normal > circumstances > > I just discovered that Bridgette sent some output to the Hotmail > account I use for posting to this list. (Bridgette, as it says in my > sig file, I only use that account for mailing to this list, and check > it only occasionally. > If you want to correspond off-list, please use the everyday e-mail > address given in my sig file.) > > So, here is syntax to generate her table, and the tests of interest. > Notice > that the results I get do not match the ones she sent me. > > * Bridgette's data. > data list list / row col kount (3f5.0). > begin data > 1 1 11 > 1 2 16 > 2 1 14 > 2 2 35 > 3 1 8 > 3 2 21 > 4 1 23 > 4 2 27 > end data. > > var lab > row "Death personality" > col "Age group" > . > val lab > row 1 "Cruel" > 2 "Gentle" > 3 "Impassive" > 4 "Other/variable" / > col 1 "Under 40" > 2 "40 plus" > . > weight by kount . > crosstabs row by col / stat = chisqr. > > * For those who have the Exact Tests module . > > CROSSTABS > /TABLES=row BY col / stat = chisqr > /METHOD=EXACT TIMER(5). > > * My results (using v18 with all patches under Windoze XP Professional): > * Pearson: Asymptotic p = .213, exact p = .216 . > * Likelihood ratio: Asymptotic p = .212, exact p = .219 . > > * Output Bridgette sent me: > * Pearson: Asymptotic p = .213, exact p = .028 . > * Likelihood ratio: Asymptotic p = .212, exact p = .047 . > > > Bridgette, what version of SPSS are you using? Have all the available > patches been applied? > > Also, regarding Age Group, why group? Do you have the actual ages? > > Cheers, > Bruce > > ===================== > To manage your subscription to SPSSX-L, send a message to > [hidden email] (not to SPSSX-L), with no body text except > the command. To leave the list, send the command SIGNOFF SPSSX-L For a > list of commands to manage subscriptions, send the command INFO > REFCARD > ----- -- Bruce Weaver [hidden email] http://sites.google.com/a/lakeheadu.ca/bweaver/ "When all else fails, RTFM." NOTE: My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. -- View this message in context: http://spssx-discussion.1045642.n5.nabble.com/Revision-control-for-SPSS-sour ce-code-tp4267835p4273911.html Sent from the SPSSX Discussion mailing list archive at Nabble.com. ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
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