R help - Aug 2010 - How to extract ICC value from irr package?

Hi, all


There are 62 samples in my data and I tested 3 times for each one, then I
want to use ICC(intraclass correlation) from irr package to test the
consistency among the tests.
*combatexpdata_p[1:62] is the first text results and combatexpdata_p[63:124]
* is the second one and *combatexpdata_p[125:186]* is the third.

Here is the result:

result<-icc(cbind(combatexpdata_p[1:62],combatexpdata_p[63:124],combatexpdata_p[125:186]),
"twoway")
result
Single Score Intraclass Correlation

  Model: twoway
  Type : consistency

  Subjects = 62
    Raters = 3
  ICC(C,1) = -0.0664

F-Test, H0: r0 = 0 ; H1: r0 > 0
 F(61,122) = 0.813 , p = 0.814

95%-Confidence Interval for ICC Population Values:
 -0.184 < ICC < 0.086


I can get the p value by result$p but when i try result$icc to get the ICC
value, it doesn't work. Is there anybody here know how to extract the
-0.0664 from the result?  Many thanks.


-- 
Chen, Chao
Psychiatry
University of Chicago
924 E 57th St, Chicago, IL 60637
U. S. A.
MOE Key Laboratory of Contemporary Anthropology and Center for
Evolutionary Biology,
School of Life Sciences and Institutes of Biomedical Sciences,
Fudan University
220# Handan Road, Shanghai (200433)
P.R.China

	[[alternative HTML version deleted]]

Hi Chen,
>From the documentation (see ?icc)  "$value: the intraclass correlation
coefficient."

As an example:
> set.seed(1)
> result <- icc(matrix(rnorm(20), ncol = 2))
> result$value
[1] -0.3148786


HTH,

Josh

On Tue, Aug 3, 2010 at 8:50 AM, chen chao <chenchaor at gmail.com>
wrote:
> Hi, all
>
>
> There are 62 samples in my data and I tested 3 times for each one, then I
> want to use ICC(intraclass correlation) from irr package to test the
> consistency among the tests.
> *combatexpdata_p[1:62] is the first text results and
combatexpdata_p[63:124]
> * is the second one and *combatexpdata_p[125:186]* is the third.
>
> Here is the result:
>
>
result<-icc(cbind(combatexpdata_p[1:62],combatexpdata_p[63:124],combatexpdata_p[125:186]),
> "twoway")
> result
> Single Score Intraclass Correlation
>
> ?Model: twoway
> ?Type : consistency
>
> ?Subjects = 62
> ? ?Raters = 3
> ?ICC(C,1) = -0.0664
>
> F-Test, H0: r0 = 0 ; H1: r0 > 0
> ?F(61,122) = 0.813 , p = 0.814
>
> 95%-Confidence Interval for ICC Population Values:
> ?-0.184 < ICC < 0.086
>
>
> I can get the p value by result$p but when i try result$icc to get the ICC
> value, it doesn't work. Is there anybody here know how to extract the
> -0.0664 from the result? ?Many thanks.
>
>
> --
> Chen, Chao
> Psychiatry
> University of Chicago
> 924 E 57th St, Chicago, IL 60637
> U. S. A.
> MOE Key Laboratory of Contemporary Anthropology and Center for
> Evolutionary Biology,
> School of Life Sciences and Institutes of Biomedical Sciences,
> Fudan University
> 220# Handan Road, Shanghai (200433)
> P.R.China
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>


-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/

And in general, you can use:
str(NameOfObject)
To understand it's *str*ucture, and where the value resides.

Cheers.

----------------Contact
Details:-------------------------------------------------------
Contact me: Tal.Galili@gmail.com |  972-52-7275845
Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
www.r-statistics.com (English)
----------------------------------------------------------------------------------------------




On Tue, Aug 3, 2010 at 6:50 PM, chen chao <chenchaor@gmail.com> wrote:
> Hi, all
>
>
> There are 62 samples in my data and I tested 3 times for each one, then I
> want to use ICC(intraclass correlation) from irr package to test the
> consistency among the tests.
> *combatexpdata_p[1:62] is the first text results and
> combatexpdata_p[63:124]
> * is the second one and *combatexpdata_p[125:186]* is the third.
>
> Here is the result:
>
>
>
result<-icc(cbind(combatexpdata_p[1:62],combatexpdata_p[63:124],combatexpdata_p[125:186]),
> "twoway")
> result
> Single Score Intraclass Correlation
>
>  Model: twoway
>  Type : consistency
>
>  Subjects = 62
>    Raters = 3
>  ICC(C,1) = -0.0664
>
> F-Test, H0: r0 = 0 ; H1: r0 > 0
>  F(61,122) = 0.813 , p = 0.814
>
> 95%-Confidence Interval for ICC Population Values:
>  -0.184 < ICC < 0.086
>
>
> I can get the p value by result$p but when i try result$icc to get the ICC
> value, it doesn't work. Is there anybody here know how to extract the
> -0.0664 from the result?  Many thanks.
>
>
> --
> Chen, Chao
> Psychiatry
> University of Chicago
> 924 E 57th St, Chicago, IL 60637
> U. S. A.
> MOE Key Laboratory of Contemporary Anthropology and Center for
> Evolutionary Biology,
> School of Life Sciences and Institutes of Biomedical Sciences,
> Fudan University
> 220# Handan Road, Shanghai (200433)
> P.R.China
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]