Curious about K-S test in NPTESTS

classic Classic list List threaded Threaded
11 messages Options
Reply | Threaded
Open this post in threaded view
|

Curious about K-S test in NPTESTS

Beckstead, Jason

Hi all,

I am working to compare various sample distributions and thought that the Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it doesn’t reveal these two obviously different distributions as significant. Syntax is below. Any insight would be appreciated.

Jason

 

DATA LIST FREE/FORM X FREQ.

BEGIN DATA.

1 1  7

1 2 24

1 3 38

1 4 24

1 5  7

2 1 20

2 2 20

2 3 20

2 4 20

2 5 20

END DATA.

WEIGHT BY FREQ.

VARIABLE LEVEL X (SCALE).

*Nonparametric Tests: Independent Samples.

NPTESTS

  /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV

  /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE

  /CRITERIA ALPHA=0.05  CILEVEL=95.

 

_____________________________________________________________

 Jason W. Beckstead, Ph.D.       

  Associate Professor/Quantitative Methodologist

  University of South Florida College of Public Health

  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA

  Statistical Editor, International Journal of Nursing Studies

  phone: +1.813.974.7667  fax: +1.813.974.4719          

  personal website:  http://personal.health.usf.edu/jbeckste/

  International Journal of Nursing Studies  http://www.elsevier.com/ijns

 

===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Jon Peck
If you duplicate the data, so that you have 20 records, the sig level goes from .367 to .068.  Triple it and the sig is .013.

Even using Exact Tests (on the original data), the K-S test sig level is .146.  Even the Mann-Whitney test does not detect the difference.

So you need more data.

On Sat, Dec 8, 2018 at 2:22 PM Beckstead, Jason <[hidden email]> wrote:

Hi all,

I am working to compare various sample distributions and thought that the Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it doesn’t reveal these two obviously different distributions as significant. Syntax is below. Any insight would be appreciated.

Jason

 

DATA LIST FREE/FORM X FREQ.

BEGIN DATA.

1 1  7

1 2 24

1 3 38

1 4 24

1 5  7

2 1 20

2 2 20

2 3 20

2 4 20

2 5 20

END DATA.

WEIGHT BY FREQ.

VARIABLE LEVEL X (SCALE).

*Nonparametric Tests: Independent Samples.

NPTESTS

  /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV

  /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE

  /CRITERIA ALPHA=0.05  CILEVEL=95.

 

_____________________________________________________________

 Jason W. Beckstead, Ph.D.       

  Associate Professor/Quantitative Methodologist

  University of South Florida College of Public Health

  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA

  Statistical Editor, International Journal of Nursing Studies

  phone: +1.813.974.7667  fax: +1.813.974.4719          

  personal website:  http://personal.health.usf.edu/jbeckste/

  International Journal of Nursing Studies  http://www.elsevier.com/ijns

 

===================== 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


--
Jon K Peck
[hidden email]

===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Rich Ulrich
In reply to this post by Beckstead, Jason
Your apparent difference is not location (mean), but "scale"
(standard deviation). Since the K-S test is sensitive to both, it
will not be especially powerful for either. 

A second generic problem is that rank-based tests, in derivation
and in most casual discussion, assume that there are no ties -- but
your data features only 5 values for 200 cases. Many ties. Sometimes
having ties is mainly notable for making the test-values wrong (so,
Jon's use of "exact stats" for p-level is good practice); sometimes,
like here, it also is reflected in a weakened test.

I put the 10 cells in a 2x5 contingency table, ignoring order, and the
online calculator gave me X2= 18.83, p< .001 (4 d.f.), which looks okay.

--
Rich Ulrich




From: SPSSX(r) Discussion <[hidden email]> on behalf of Beckstead, Jason <[hidden email]>
Sent: Saturday, December 8, 2018 4:21 PM
To: [hidden email]
Subject: Curious about K-S test in NPTESTS
 

Hi all,

I am working to compare various sample distributions and thought that the Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it doesn’t reveal these two obviously different distributions as significant. Syntax is below. Any insight would be appreciated.

Jason

 

DATA LIST FREE/FORM X FREQ.

BEGIN DATA.

1 1  7

1 2 24

1 3 38

1 4 24

1 5  7

2 1 20

2 2 20

2 3 20

2 4 20

2 5 20

END DATA.

WEIGHT BY FREQ.

VARIABLE LEVEL X (SCALE).

*Nonparametric Tests: Independent Samples.

NPTESTS

  /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV

  /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE

  /CRITERIA ALPHA=0.05  CILEVEL=95.

 

_____________________________________________________________

 Jason W. Beckstead, Ph.D.       

  Associate Professor/Quantitative Methodologist

  University of South Florida College of Public Health

  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA

  Statistical Editor, International Journal of Nursing Studies

  phone: +1.813.974.7667  fax: +1.813.974.4719          

  personal website:  http://personal.health.usf.edu/jbeckste/

  International Journal of Nursing Studies  http://www.elsevier.com/ijns

 

===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Beckstead, Jason
Thanks to all. You guys confirmed my hunch. I guess that the best way to compare the difference between two or more distributions of 5 values (like those resulting from different sets of verbal anchors on Likert-type scales) is to use chi-square test.
Jason

sent via me phone


From: Rich Ulrich <[hidden email]>
Sent: Saturday, December 8, 2018 8:19:14 PM
To: [hidden email]; Beckstead, Jason
Subject: Re: Curious about K-S test in NPTESTS
 
Your apparent difference is not location (mean), but "scale"
(standard deviation). Since the K-S test is sensitive to both, it
will not be especially powerful for either. 

A second generic problem is that rank-based tests, in derivation
and in most casual discussion, assume that there are no ties -- but
your data features only 5 values for 200 cases. Many ties. Sometimes
having ties is mainly notable for making the test-values wrong (so,
Jon's use of "exact stats" for p-level is good practice); sometimes,
like here, it also is reflected in a weakened test.

I put the 10 cells in a 2x5 contingency table, ignoring order, and the
online calculator gave me X2= 18.83, p< .001 (4 d.f.), which looks okay.

--
Rich Ulrich




From: SPSSX(r) Discussion <[hidden email]> on behalf of Beckstead, Jason <[hidden email]>
Sent: Saturday, December 8, 2018 4:21 PM
To: [hidden email]
Subject: Curious about K-S test in NPTESTS
 

Hi all,

I am working to compare various sample distributions and thought that the Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it doesn’t reveal these two obviously different distributions as significant. Syntax is below. Any insight would be appreciated.

Jason

 

DATA LIST FREE/FORM X FREQ.

BEGIN DATA.

1 1  7

1 2 24

1 3 38

1 4 24

1 5  7

2 1 20

2 2 20

2 3 20

2 4 20

2 5 20

END DATA.

WEIGHT BY FREQ.

VARIABLE LEVEL X (SCALE).

*Nonparametric Tests: Independent Samples.

NPTESTS

  /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV

  /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE

  /CRITERIA ALPHA=0.05  CILEVEL=95.

 

_____________________________________________________________

 Jason W. Beckstead, Ph.D.       

  Associate Professor/Quantitative Methodologist

  University of South Florida College of Public Health

  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA

  Statistical Editor, International Journal of Nursing Studies

  phone: +1.813.974.7667  fax: +1.813.974.4719          

  personal website:  http://personal.health.usf.edu/jbeckste/

  International Journal of Nursing Studies  http://www.elsevier.com/ijns

 

===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Rich Ulrich
A likert-type scaling has order, and the ordinary contingency table
does not respect that. You have a 2 d.f. test rather than a 4 d.f.
test, and the /usual/ difference between distributions is the mean.
Having a hole in likert-type responses (1s, least number of 2s, 3s,
4s, 5s) would be unusual and suspicious all by itself, but is among
what the contingency table tests.

If you want a test on variances, in addition to the usual test on means,
the "powerful" manner of testing is to conduct two separate tests, each
with 1 d.f.   I think it also would be clearer in a report on results to describe
two tests.

For the simple variance-ratio F-test, I get F=1.923, p < .001 (same p-report
I gave for the 2x5 table).  With more precision: this one is p= 0.00069, while
the 2x5 table was  p= 0.0008-something.

--
Rich Ulrich


From: Beckstead, Jason <[hidden email]>
Sent: Sunday, December 9, 2018 1:14 PM
To: [hidden email]; Rich Ulrich
Subject: Re: Curious about K-S test in NPTESTS
 
Thanks to all. You guys confirmed my hunch. I guess that the best way to compare the difference between two or more distributions of 5 values (like those resulting from different sets of verbal anchors on Likert-type scales) is to use chi-square test.
Jason

sent via me phone


From: Rich Ulrich <[hidden email]>
Sent: Saturday, December 8, 2018 8:19:14 PM
To: [hidden email]; Beckstead, Jason
Subject: Re: Curious about K-S test in NPTESTS
 
Your apparent difference is not location (mean), but "scale"
(standard deviation). Since the K-S test is sensitive to both, it
will not be especially powerful for either. 

A second generic problem is that rank-based tests, in derivation
and in most casual discussion, assume that there are no ties -- but
your data features only 5 values for 200 cases. Many ties. Sometimes
having ties is mainly notable for making the test-values wrong (so,
Jon's use of "exact stats" for p-level is good practice); sometimes,
like here, it also is reflected in a weakened test.

I put the 10 cells in a 2x5 contingency table, ignoring order, and the
online calculator gave me X2= 18.83, p< .001 (4 d.f.), which looks okay.

--
Rich Ulrich




From: SPSSX(r) Discussion <[hidden email]> on behalf of Beckstead, Jason <[hidden email]>
Sent: Saturday, December 8, 2018 4:21 PM
To: [hidden email]
Subject: Curious about K-S test in NPTESTS
 

Hi all,

I am working to compare various sample distributions and thought that the Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it doesn’t reveal these two obviously different distributions as significant. Syntax is below. Any insight would be appreciated.

Jason

 

DATA LIST FREE/FORM X FREQ.

BEGIN DATA.

1 1  7

1 2 24

1 3 38

1 4 24

1 5  7

2 1 20

2 2 20

2 3 20

2 4 20

2 5 20

END DATA.

WEIGHT BY FREQ.

VARIABLE LEVEL X (SCALE).

*Nonparametric Tests: Independent Samples.

NPTESTS

  /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV

  /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE

  /CRITERIA ALPHA=0.05  CILEVEL=95.

 

_____________________________________________________________

 Jason W. Beckstead, Ph.D.       

  Associate Professor/Quantitative Methodologist

  University of South Florida College of Public Health

  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA

  Statistical Editor, International Journal of Nursing Studies

  phone: +1.813.974.7667  fax: +1.813.974.4719          

  personal website:  http://personal.health.usf.edu/jbeckste/

  International Journal of Nursing Studies  http://www.elsevier.com/ijns

 

===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Bruce Weaver
Administrator
CROSSTABS also reports a Chi-square test of linear-by-linear association,
which you could use in this situation.  See David Howell's nice note on it
here:

https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSq.html

By the way, for those who may not have heard, David Howell died on Oct 4 of
this year.  He'd been fighting cancer for about 8 years.  



Rich Ulrich wrote

> A likert-type scaling has order, and the ordinary contingency table
> does not respect that. You have a 2 d.f. test rather than a 4 d.f.
> test, and the /usual/ difference between distributions is the mean.
> Having a hole in likert-type responses (1s, least number of 2s, 3s,
> 4s, 5s) would be unusual and suspicious all by itself, but is among
> what the contingency table tests.
>
> If you want a test on variances, in addition to the usual test on means,
> the "powerful" manner of testing is to conduct two separate tests, each
> with 1 d.f.   I think it also would be clearer in a report on results to
> describe
> two tests.
>
> For the simple variance-ratio F-test, I get F=1.923, p < .001 (same
> p-report
> I gave for the 2x5 table).  With more precision: this one is p= 0.00069,
> while
> the 2x5 table was  p= 0.0008-something.
>
> --
> Rich Ulrich
>
> ________________________________
> From: Beckstead, Jason &lt;

> jbeckste@.usf

> &gt;
> Sent: Sunday, December 9, 2018 1:14 PM
> To:

> spssx-l@.uga

> ; Rich Ulrich
> Subject: Re: Curious about K-S test in NPTESTS
>
> Thanks to all. You guys confirmed my hunch. I guess that the best way to
> compare the difference between two or more distributions of 5 values (like
> those resulting from different sets of verbal anchors on Likert-type
> scales) is to use chi-square test.
> Jason
>
> sent via me phone
>
> ________________________________
> From: Rich Ulrich &lt;

> rich-ulrich@

> &gt;
> Sent: Saturday, December 8, 2018 8:19:14 PM
> To:

> SPSSX-L@.UGA

> ; Beckstead, Jason
> Subject: Re: Curious about K-S test in NPTESTS
>
> Your apparent difference is not location (mean), but "scale"
> (standard deviation). Since the K-S test is sensitive to both, it
> will not be especially powerful for either.
>
> A second generic problem is that rank-based tests, in derivation
> and in most casual discussion, assume that there are no ties -- but
> your data features only 5 values for 200 cases. Many ties. Sometimes
> having ties is mainly notable for making the test-values wrong (so,
> Jon's use of "exact stats" for p-level is good practice); sometimes,
> like here, it also is reflected in a weakened test.
>
> I put the 10 cells in a 2x5 contingency table, ignoring order, and the
> online calculator gave me X2= 18.83, p< .001 (4 d.f.), which looks okay.
>
> --
> Rich Ulrich
>
>
>
> ________________________________
> From: SPSSX(r) Discussion &lt;

> SPSSX-L@.UGA

> &gt; on behalf of Beckstead, Jason &lt;

> jbeckste@.usf

> &gt;
> Sent: Saturday, December 8, 2018 4:21 PM
> To:

> SPSSX-L@.UGA

> Subject: Curious about K-S test in NPTESTS
>
>
> Hi all,
>
> I am working to compare various sample distributions and thought that the
> Kolmogorov-Smirnov test in NPTESTS would be appropriate. However, it
> doesn’t reveal these two obviously different distributions as significant.
> Syntax is below. Any insight would be appreciated.
>
> Jason
>
>
>
> DATA LIST FREE/FORM X FREQ.
>
> BEGIN DATA.
>
> 1 1  7
>
> 1 2 24
>
> 1 3 38
>
> 1 4 24
>
> 1 5  7
>
> 2 1 20
>
> 2 2 20
>
> 2 3 20
>
> 2 4 20
>
> 2 5 20
>
> END DATA.
>
> WEIGHT BY FREQ.
>
> VARIABLE LEVEL X (SCALE).
>
> *Nonparametric Tests: Independent Samples.
>
> NPTESTS
>
>   /INDEPENDENT TEST (X) GROUP (FORM) KOLMOGOROV_SMIRNOV
>
>   /MISSING SCOPE=ANALYSIS USERMISSING=EXCLUDE
>
>   /CRITERIA ALPHA=0.05  CILEVEL=95.
>
>
>
> _____________________________________________________________
>
>  Jason W. Beckstead, Ph.D.
>
>   Associate Professor/Quantitative Methodologist
>
>   University of South Florida College of Public Health
>
>   13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA
>
>   Statistical Editor, International Journal of Nursing Studies
>
>   phone: +1.813.974.7667  fax: +1.813.974.4719
>
>   personal website:  http://personal.health.usf.edu/jbeckste/
>
>   International Journal of Nursing Studies  http://www.elsevier.com/ijns
>
>
>
> ===================== To manage your subscription to SPSSX-L, send a
> message to

> LISTSERV@.UGA

> &lt;mailto:

> LISTSERV@.UGA

> &gt; (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

> LISTSERV@.UGA

>  (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.

--
Sent from: http://spssx-discussion.1045642.n5.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
--
Bruce Weaver
bweaver@lakeheadu.ca
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.
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Anthony Babinec
Bruce,
You need a period in that URL:

https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSq.html

Sad news about David Howell.

Tony Babinec

-----Original Message-----
From: SPSSX(r) Discussion <[hidden email]> On Behalf Of Bruce Weaver
Sent: Sunday, December 9, 2018 4:13 PM
To: [hidden email]
Subject: Re: Curious about K-S test in NPTESTS

CROSSTABS also reports a Chi-square test of linear-by-linear association, which you could use in this situation.  See David Howell's nice note on it
here:

https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSqhtml

By the way, for those who may not have heard, David Howell died on Oct 4 of this year.  He'd been fighting cancer for about 8 years.  



Rich Ulrich wrote

> A likert-type scaling has order, and the ordinary contingency table
> does not respect that. You have a 2 d.f. test rather than a 4 d.f.
> test, and the /usual/ difference between distributions is the mean.
> Having a hole in likert-type responses (1s, least number of 2s, 3s,
> 4s, 5s) would be unusual and suspicious all by itself, but is among
> what the contingency table tests.
>
> If you want a test on variances, in addition to the usual test on
> means, the "powerful" manner of testing is to conduct two separate tests, each
> with 1 d.f.   I think it also would be clearer in a report on results to
> describe
> two tests.
>
> For the simple variance-ratio F-test, I get F=1.923, p < .001 (same
> p-report I gave for the 2x5 table).  With more precision: this one is
> p= 0.00069, while the 2x5 table was  p= 0.0008-something.
>
> --
> 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Rich Ulrich
I don't know why that particular comment from David Howell's page was
included, but the test and p-value for non-linear component described the
data on Howell's page.

Applying the algorithm for "non-linear" to the artificial data from Jason -
the linear component is exactly 0, so the achieved X2 value is also the
3-df  test, with smaller p-value because it has 3 df, not 4.

Sad, about David.

--
Rich Ulrich

From: SPSSX(r) Discussion <[hidden email]> on behalf of Anthony Babinec <[hidden email]>
Sent: Sunday, December 9, 2018 5:34 PM
To: [hidden email]
Subject: Re: Curious about K-S test in NPTESTS
 
Bruce,
You need a period in that URL:

https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSq.html

Sad news about David Howell.

Tony Babinec

-----Original Message-----
From: SPSSX(r) Discussion <[hidden email]> On Behalf Of Bruce Weaver
Sent: Sunday, December 9, 2018 4:13 PM
To: [hidden email]
Subject: Re: Curious about K-S test in NPTESTS

CROSSTABS also reports a Chi-square test of linear-by-linear association, which you could use in this situation.  See David Howell's nice note on it
here:

https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSqhtml

By the way, for those who may not have heard, David Howell died on Oct 4 of this year.  He'd been fighting cancer for about 8 years. 



Rich Ulrich wrote
> A likert-type scaling has order, and the ordinary contingency table
> does not respect that. You have a 2 d.f. test rather than a 4 d.f.
> test, and the /usual/ difference between distributions is the mean.
> Having a hole in likert-type responses (1s, least number of 2s, 3s,
> 4s, 5s) would be unusual and suspicious all by itself, but is among
> what the contingency table tests.
>
> If you want a test on variances, in addition to the usual test on
> means, the "powerful" manner of testing is to conduct two separate tests, each
> with 1 d.f.   I think it also would be clearer in a report on results to
> describe
> two tests.
>
> For the simple variance-ratio F-test, I get F=1.923, p < .001 (same
> p-report I gave for the 2x5 table).  With more precision: this one is
> p= 0.00069, while the 2x5 table was  p= 0.0008-something.
>
> --
> 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
===================== 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
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Bruce Weaver
Administrator
Rich is right.  Here are the results of Howell's analysis on the data posted
in this thread.

Test                            Value df      p  Percent
Pearson Chi-Square             18.832  4   .001    100.0
Linear-by-Linear Association     .000  1  1.000       .0
Deviation from Linearity       18.832  3   .000    100.0



Rich Ulrich wrote

> I don't know why that particular comment from David Howell's page was
> included, but the test and p-value for non-linear component described the
> data on Howell's page.
>
> Applying the algorithm for "non-linear" to the artificial data from Jason
> -
> the linear component is exactly 0, so the achieved X2 value is also the
> 3-df  test, with smaller p-value because it has 3 df, not 4.
>
> Sad, about David.
>
> --
> Rich Ulrich





-----
--
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.

--
Sent from: http://spssx-discussion.1045642.n5.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
--
Bruce Weaver
bweaver@lakeheadu.ca
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.
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Bruce Weaver
Administrator
This post was updated on .
In reply to this post by Anthony Babinec
That's interesting.  When I look at my post in Nabble (first link below), the
period is there.  When I look at Tony's reply in Nabble (second link below),
the period is missing.  Gremlins, perhaps?  ;-)  

http://spssx-discussion.1045642.n5.nabble.com/Curious-about-K-S-test-in-NPTESTS-tp5737122p5737127.html

http://spssx-discussion.1045642.n5.nabble.com/Curious-about-K-S-test-in-NPTESTS-tp5737122p5737128.html

EDIT:  I mean that when I look at the ~copy~ of my post shown in Tony's reply, the period is missing!


Anthony Babinec wrote
> Bruce,
> You need a period in that URL:
>
> https://www.uvm.edu/~dhowell/StatPages/More_Stuff/OrdinalChisq/OrdinalChiSq.html
>
> Sad news about David Howell.
>
> Tony Babinec





-----
--
Bruce Weaver
bweaver@lakeheadu.ca
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.

--
Sent from: http://spssx-discussion.1045642.n5.nabble.com/

=====================
To manage your subscription to SPSSX-L, send a message to
LISTSERV@LISTSERV.UGA.EDU (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
bweaver@lakeheadu.ca
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.
Reply | Threaded
Open this post in threaded view
|

Re: Curious about K-S test in NPTESTS

Beckstead, Jason
In reply to this post by Bruce Weaver
Thanks to all of you who have weighed in on this one.
BIG PICTURE: I am investigating how the use of different sets of verbal anchors for 5-point Likert-type response scales alter the distributions of the responses to items. I have 6 different sets of labels. I have 27 items that were used to create 6 versions of a questionnaire. Each questionnaire contained all 27 items but used a different set of verbal anchors for the 5-point scale. Students from a very large class were randomly assigned to complete one of the questionnaires. I have approximately 125 subjects in each of the 6 conditions.
Analysis plan: 1) for each item I am comparing the distribution of responses across conditions using a chi-square test. I am not using the linear-by-linear test, because it is my understanding that this test assumes that the distances between adjacent categories is equal.
2) also, I am conducting item-metric repeated measures ANOVAs. In this approach, the items are treated as the subjects (n=27). For each item I have computed standard deviation, skewness, and kurtosis. One ANOVA, for example, treats the standard deviations of the items a the DV. I repeat this type of analysis on the item-skewnesses, and on the kurtosis values.

Any comments, or suggestions welcome.
Jason


_____________________________________________________________
 Jason W. Beckstead, Ph.D.       
  Associate Professor/Quantitative Methodologist
  University of South Florida College of Public Health
  13201 Bruce B. Downs Blvd., MDC56, Tampa, FL 33612, USA
  Statistical Editor, International Journal of Nursing Studies
  phone: +1.813.974.7667  fax: +1.813.974.4719          
  personal website:  http://personal.health.usf.edu/jbeckste/
  International Journal of Nursing Studies  http://www.elsevier.com/ijns

-----Original Message-----
From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Bruce Weaver
Sent: Monday, December 10, 2018 8:11 AM
To: [hidden email]
Subject: Re: Curious about K-S test in NPTESTS

Rich is right.  Here are the results of Howell's analysis on the data posted
in this thread.

Test                            Value df      p  Percent
Pearson Chi-Square             18.832  4   .001    100.0
Linear-by-Linear Association     .000  1  1.000       .0
Deviation from Linearity       18.832  3   .000    100.0



Rich Ulrich wrote

> I don't know why that particular comment from David Howell's page was
> included, but the test and p-value for non-linear component described the
> data on Howell's page.
>
> Applying the algorithm for "non-linear" to the artificial data from Jason
> -
> the linear component is exactly 0, so the achieved X2 value is also the
> 3-df  test, with smaller p-value because it has 3 df, not 4.
>
> Sad, about David.
>
> --
> Rich Ulrich





-----
--
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.

--
Sent from: http://spssx-discussion.1045642.n5.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