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Re: example output from crosstabs column proportions

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msherman

Re: example output from crosstabs column proportions

Below is an output from crosstabs using column proportion testing. But what does it show? That 50/50 is significantly different from 20/80? Martin Sherman

x * y Crosstabulation
y
1.00 2.00 Total
x 1.00 Count 40 a 10 b 50
% within x 80.0% 20.0% 100.0%
% within y 50.0% 20.0% 38.5%
2.00 Count 40 a 40 b 80
% within x 50.0% 50.0% 100.0%
% within y 50.0% 80.0% 61.5%
Total Count 80 50 130
% within x 61.5% 38.5% 100.0%
% within y 100.0% 100.0% 100.0%
Each subscript letter denotes a subset of y categories whose column proportions do not differ significantly from each other at the .05 level.

-----Original Message-----
From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bruce Weaver
Sent: Wednesday, March 09, 2011 6:10 PM
To: [hidden email]
Subject: Re: chi-square post-hoc tests

This is the second or third time I've seen someone mention z-tests under CROSSTABS. I'm not familiar with that--is it new in v19?

Thanks,
Bruce

Bridgette Portman wrote:

>
> That seems like so much extra work. What about the "compare column
> proportions" option under "z-tests" in Crosstabs --> Cells? Is anyone
> familiar with using this? If I am interpreting it right, it allows for
> the kind of pairwise comparisons I'm trying to do, with the option for
> a Bonferroni adjustment to the alpha level.
>
> Bridgette
>
>
>> If one of the elements remains as 2 levels (e.g., 2 X 3), use
>> logistic regression, with the 2-level variable as the outcome. Then
>> use appropriate a priori contrasts to disentangle the df (2 df in the
>> case of the 3 level variable).
>>
>> If none of the elements are 2 levels, then you need to consider a
>> multinomial logistic regression.
>>
>> Joe Burleson
>>
>> -----Original Message-----
>> From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf
>> Of Bridgette Portman
>> Sent: Wednesday, March 09, 2011 1:00 AM
>> To: [hidden email]
>> Subject: chi-square post-hoc tests
>>
>> I have another question.
>>
>> I'm confused about how to perform post-hoc tests for chi-square
>> contingency tables larger than 2 x 2. I've been reading up on it in
>> books and on the internet, and there seem to be two different methods advised.
>> Some say to do multiple pairwise comparisons (2x2 tables) with a
>> Bonferroni correction. Others say to look at the standardized residuals.
>> I'm not sure which is the better way. Is there any easy way to
>> perform posthoc tests on contingency tables in SPSS?
>>
>> Thanks,
>> 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
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>>
>>
>
> =====================
> To manage your subscription to SPSSX-L, send a message to
> [hidden email] (not to SPSSX-L), with no body text except
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> REFCARD
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-----
--
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/Anova-SS1-vSS3-using-v-17-0-tp3412630p3420116.html
Sent from the SPSSX Discussion mailing list archive at Nabble.com.

=====================
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=====================
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[hidden email] (not to SPSSX-L), with no body text except the
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For a list of commands to manage subscriptions, send the command
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Bridgette Portman

Re: example output from crosstabs column proportions

Yeah it's confusing. The way I think I would interpret that is that X
Group 1 and X Group 2 differ significantly in their proportions of Y.
Which isn't necessary because it's only a 2x2 table so we already know
that by just looking at the chi-square statistic.

Am I right?

> Below is an output from crosstabs using column proportion testing. But
> what does it show? That 50/50 is significantly different from 20/80?
> Martin Sherman
>
> x * y Crosstabulation
> y
> 1.00 2.00 Total
> x 1.00 Count 40 a 10 b 50
> % within x 80.0% 20.0% 100.0%
> % within y 50.0% 20.0% 38.5%
> 2.00 Count 40 a 40 b 80
> % within x 50.0% 50.0% 100.0%
> % within y 50.0% 80.0% 61.5%
> Total Count 80 50 130
> % within x 61.5% 38.5% 100.0%
> % within y 100.0% 100.0% 100.0%
> Each subscript letter denotes a subset of y categories whose column
> proportions do not differ significantly from each other at the .05 level.
>
>
> -----Original Message-----
> From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of
> Bruce Weaver
> Sent: Wednesday, March 09, 2011 6:10 PM
> To: [hidden email]
> Subject: Re: chi-square post-hoc tests
>
> This is the second or third time I've seen someone mention z-tests under
> CROSSTABS. I'm not familiar with that--is it new in v19?
>
> Thanks,
> Bruce
>
>
>
> Bridgette Portman wrote:
>>
>> That seems like so much extra work. What about the "compare column
>> proportions" option under "z-tests" in Crosstabs --> Cells? Is anyone
>> familiar with using this? If I am interpreting it right, it allows for
>> the kind of pairwise comparisons I'm trying to do, with the option for
>> a Bonferroni adjustment to the alpha level.
>>
>> Bridgette
>>
>>
>>> If one of the elements remains as 2 levels (e.g., 2 X 3), use
>>> logistic regression, with the 2-level variable as the outcome. Then
>>> use appropriate a priori contrasts to disentangle the df (2 df in the
>>> case of the 3 level variable).
>>>
>>> If none of the elements are 2 levels, then you need to consider a
>>> multinomial logistic regression.
>>>
>>> Joe Burleson
>>>
>>> -----Original Message-----
>>> From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf
>>> Of Bridgette Portman
>>> Sent: Wednesday, March 09, 2011 1:00 AM
>>> To: [hidden email]
>>> Subject: chi-square post-hoc tests
>>>
>>> I have another question.
>>>
>>> I'm confused about how to perform post-hoc tests for chi-square
>>> contingency tables larger than 2 x 2. I've been reading up on it in
>>> books and on the internet, and there seem to be two different methods
>>> advised.
>>> Some say to do multiple pairwise comparisons (2x2 tables) with a
>>> Bonferroni correction. Others say to look at the standardized
>>> residuals.
>>> I'm not sure which is the better way. Is there any easy way to
>>> perform posthoc tests on contingency tables in SPSS?
>>>
>>> Thanks,
>>> 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
>>>
>>>
>>
>> =====================
>> 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/Anova-SS1-vSS3-using-v-17-0-tp3412630p3420116.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
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> INFO REFCARD
>
>

=====================
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For a list of commands to manage subscriptions, send the command
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Bridgette Portman

Re: example output from crosstabs column proportions

In reply to this post by msherman

Here is another example; this is from my actual dataset, and it's a larger
than 2x2 table. Variables are Party (4 levels) and Tea Party (2 levels,
yes or no). I used compare column percentages, with Bonferroni correction.
And this is what I got. Hope it lines up right.

Am I interpreting this correctly to say that it means Republicans differ
significantly from Democrats, Libertarians, and Socialists in terms of the
proportions of them who are members of the Tea Party, and also
Libertarians differ significantly from Democrats and Socialists, but
Socialists and Democrats don't differ from each other?

Tea Party * Party Crosstabulation

Party
Republican Democrat Libertarian Socialist
Tea Party No Count 23a 76b 41c
45b
% within Party 41.8% 100.0% 69.5% 100.0%

Yes Count 32a 0b
18c 0b
% within Party 58.2% .0% 30.5% .0%

Each subscript letter denotes a subset of Party categories whose column
proportions do not differ significantly from each other at the .05 level.

Bridgette Portman

Re: example output from crosstabs column proportions

Shoot, it didn't line up, let me try again:

Tea Party * Party Crosstabulation

Republican Democrat Libertarian Socialist
Tea Party No Count 23a 76b 41c 45b 185
% within Party 41.8% 100.0% 69.5% 100.0%
Yes Count 32a 0b 18c 0b 50
% within Party 58.2% .0% 30.5% .0%
Total Count 55 76 59 45 235
% within Party 100.0% 100.0% 100.0% 100.0%

Each subscript letter denotes a subset of Party categories whose column
proportions do not differ significantly from each other at the .05 level.

> Here is another example; this is from my actual dataset, and it's a larger
> than 2x2 table. Variables are Party (4 levels) and Tea Party (2 levels,
> yes or no). I used compare column percentages, with Bonferroni correction.
> And this is what I got. Hope it lines up right.
>
> Am I interpreting this correctly to say that it means Republicans differ
> significantly from Democrats, Libertarians, and Socialists in terms of the
> proportions of them who are members of the Tea Party, and also
> Libertarians differ significantly from Democrats and Socialists, but
> Socialists and Democrats don't differ from each other?
>
>
> Tea Party * Party Crosstabulation
>
> Party
> Republican Democrat Libertarian Socialist
> Tea Party No Count 23a 76b 41c
> 45b
> % within Party 41.8% 100.0% 69.5% 100.0%
>
> Yes Count 32a 0b
> 18c 0b
> % within Party 58.2% .0% 30.5% .0%
>
> Each subscript letter denotes a subset of Party categories whose column
> proportions do not differ significantly from each other at the .05 level.
>
>
>
>
>
>
>
>
>
>> Below is an output from crosstabs using column proportion testing. But
>> what does it show? That 50/50 is significantly different from 20/80?
>> Martin Sherman
>>
>> x * y Crosstabulation
>> y
>> 1.00 2.00 Total
>> x 1.00 Count 40 a 10 b 50
>> % within x 80.0% 20.0% 100.0%
>> % within y 50.0% 20.0% 38.5%
>> 2.00 Count 40 a 40 b 80
>> % within x 50.0% 50.0% 100.0%
>> % within y 50.0% 80.0% 61.5%
>> Total Count 80 50 130
>> % within x 61.5% 38.5% 100.0%
>> % within y 100.0% 100.0% 100.0%
>> Each subscript letter denotes a subset of y categories whose column
>> proportions do not differ significantly from each other at the .05
>> level.
>>
>>
>> -----Original Message-----
>> From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of
>> Bruce Weaver
>> Sent: Wednesday, March 09, 2011 6:10 PM
>> To: [hidden email]
>> Subject: Re: chi-square post-hoc tests
>>
>> This is the second or third time I've seen someone mention z-tests under
>> CROSSTABS. I'm not familiar with that--is it new in v19?
>>
>> Thanks,
>> Bruce
>>
>>
>>
>> Bridgette Portman wrote:
>>>
>>> That seems like so much extra work. What about the "compare column
>>> proportions" option under "z-tests" in Crosstabs --> Cells? Is anyone
>>> familiar with using this? If I am interpreting it right, it allows for
>>> the kind of pairwise comparisons I'm trying to do, with the option for
>>> a Bonferroni adjustment to the alpha level.
>>>
>>> Bridgette
>>>
>>>
>>>> If one of the elements remains as 2 levels (e.g., 2 X 3), use
>>>> logistic regression, with the 2-level variable as the outcome. Then
>>>> use appropriate a priori contrasts to disentangle the df (2 df in the
>>>> case of the 3 level variable).
>>>>
>>>> If none of the elements are 2 levels, then you need to consider a
>>>> multinomial logistic regression.
>>>>
>>>> Joe Burleson
>>>>
>>>> -----Original Message-----
>>>> From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf
>>>> Of Bridgette Portman
>>>> Sent: Wednesday, March 09, 2011 1:00 AM
>>>> To: [hidden email]
>>>> Subject: chi-square post-hoc tests
>>>>
>>>> I have another question.
>>>>
>>>> I'm confused about how to perform post-hoc tests for chi-square
>>>> contingency tables larger than 2 x 2. I've been reading up on it in
>>>> books and on the internet, and there seem to be two different methods
>>>> advised.
>>>> Some say to do multiple pairwise comparisons (2x2 tables) with a
>>>> Bonferroni correction. Others say to look at the standardized
>>>> residuals.
>>>> I'm not sure which is the better way. Is there any easy way to
>>>> perform posthoc tests on contingency tables in SPSS?
>>>>
>>>> Thanks,
>>>> 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
>>>>
>>>>
>>>
>>> =====================
>>> 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/Anova-SS1-vSS3-using-v-17-0-tp3412630p3420116.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
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>>
>>
>
>