Re: [R] R help contingency table

2016-06-20 Thread Jim Lemon
Hi Lucie,
You can visualize this using the sizetree function (plotrix). You
supply a data frame of the individual choice sequences.

# form a data frame of "random" choices
coltrans<-data.frame(choice1=sample(c("High","Medium","Low"),100,TRUE),
 choice2=sample(c("High","Medium","Low"),100,TRUE))
sizetree(coltrans,main="Random color choice transitions")
# test the two way table of transitions for independence
chisq.test(table(coltrans))
# now try a data frame of "habitual" choices
coltrans2<-data.frame(choice1=rep(c("High","Medium","Low"),c(33,33,34)),
 choice2=c(sample(c("High","Medium","Low"),33,TRUE,prob=c(0.6,0.2,0.2)),
 sample(c("High","Medium","Low"),33,TRUE,prob=c(0.2,0.6,0.2)),
 sample(c("High","Medium","Low"),34,TRUE,prob=c(0.2,0.2,0.6
sizetree(coltrans2,main="Habitual color choice transitions")
# test the table again
chisq.test(table(coltrans2))

This may be what you want.

Jim


On Mon, Jun 20, 2016 at 12:09 PM, Lucie Dupond  wrote:
> Hello,
> I'm sorry if my question is really basic, but I'm having some troubles with 
> the statistics for my thesis, and especially the khi square test and 
> contingency tables.
>
> For what I understood, there are two "kinds" of khisquare test, that are 
> quite similar :
> - Homogeneity, when we have one variable and we want to compare it with a 
> theorical distribution
> - Independence test, when we have 2 variable and we want to see if they are 
> linked
>
> -- -
>
> I'm working on color transitions, with 3 possible factors : « High » , « 
> Medium » and « Low »
> I want to know if an individual will go preferably from a color « High » to 
> another color « High », more than from a color « High » to a color « Medium » 
> (for example)
>
> I have this table :
>
> trans1<-c(51,17,27,12,21,13,37,15,60)
> transitions1<-matrix(trans1, nrow=3, ncol=3, byrow=T)
> rownames(transitions1) <- c("High"," Medium", "Low")
> colnames(transitions1) <- c("High"," Medium", "Low")
>
> The first colomn is showing the first color, and the second is showing the 
> second color of the transition
>
> It looks like I'm in the case of an Independence test, in order to see if the 
> variable "second color" is linked to the "first color".
>
> So I'm making the test :
>
> chisq.test(transitions1)
>
>
> (If I understood well, the test on the matrix is the independence  test, and 
> the test on the vector trans1 is the homogeneity test ?)
>
> The result is significatif, it means that some transitions are prefered.
>
> My problem is that I have other transition tables like this one (with other 
> individuals or other conditions)
> For example, I also have this one :
>
>
> trans2<-c(13,7,8,5,16,18,11,8,17)
> transitions2<-matrix(trans2, nrow=3, ncol=3, byrow=T)
> rownames(transitions2) <- c("High","Low", "Stick")
> colnames(transitions2) <- c("High","Low", "Stick")
>
> I want to know if the "prefered" transitions in the table 1 are the same in 
> the table 2.
> But if I try a khisquare test on those two matrix, R only takes the first one.
>
> How can I compare those tables
> Maybe with another test ?
>
> Thanks in advance !
>
> Kind regards
>
> Lucie S.
>
> [[alternative HTML version deleted]]
>
>
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

Re: [R] R help contingency table

2016-06-20 Thread Lucie Dupond
Thank you for your answer !

I'm sorry, i've made a mistake in the second matrix, they should have the same 
row/column labels, I just used another label vector by mistake.

My supervisor doesn't have a solution for this, and neither have every one I 
asked around me.

Thanks for your solution, but I'm afraid that I will loose the interaction 
between the variable "first color" and "second color" if I convert the matrix 
into a vector.


Thank you for your help




De : David L Carlson <dcarl...@tamu.edu>
Envoy� : lundi 20 juin 2016 21:06
� : Lucie Dupond; r-help@r-project.org
Objet : RE: R help contingency table

You should consult with your adviser or someone at your institution who has 
more experience in statistical analysis than you do. You want to compare the 
matrices, but the row/column labels are different so you may be comparing 
completely different categories.

Technically, you need to convert the two matrices into a single matrix. You can 
do that by converting each into a vector with the c() function. BUT this will 
compare High with High, Medium with Low, and Low with Stick which seems 
inadvisable.

> rbind(c(transitions1), c(transitions2))
 [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
[1,]   51   12   37   17   21   15   27   13   60
[2,]   135   117   1688   18   17
> chisq.test(rbind(c(transitions1), c(transitions2)))

Pearson's Chi-squared test

data:  rbind(c(transitions1), c(transitions2))
X-squared = 22.411, df = 8, p-value = 0.004208

Warning message:
In chisq.test(rbind(c(transitions1), c(transitions2))) :
  Chi-squared approximation may be incorrect

-
David L Carlson
Department of Anthropology
Texas A University
College Station, TX 77840-4352

-Original Message-
From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Lucie Dupond
Sent: Sunday, June 19, 2016 9:10 PM
To: r-help@r-project.org
Subject: [R] R help contingency table

Hello,
I'm sorry if my question is really basic, but I'm having some troubles with the 
statistics for my thesis, and especially the khi square test and contingency 
tables.

For what I understood, there are two "kinds" of khisquare test, that are quite 
similar :
- Homogeneity, when we have one variable and we want to compare it with a 
theorical distribution
- Independence test, when we have 2 variable and we want to see if they are 
linked

-- -

I'm working on color transitions, with 3 possible factors : ? High ? , ? Medium 
? and ? Low ?
I want to know if an individual will go preferably from a color ? High ? to 
another color ? High ?, more than from a color ? High ? to a color ? Medium ? 
(for example)

I have this table :

trans1<-c(51,17,27,12,21,13,37,15,60)
transitions1<-matrix(trans1, nrow=3, ncol=3, byrow=T)
rownames(transitions1) <- c("High"," Medium", "Low")
colnames(transitions1) <- c("High"," Medium", "Low")

The first colomn is showing the first color, and the second is showing the 
second color of the transition

It looks like I'm in the case of an Independence test, in order to see if the 
variable "second color" is linked to the "first color".

So I'm making the test :

chisq.test(transitions1)


(If I understood well, the test on the matrix is the independence  test, and 
the test on the vector trans1 is the homogeneity test ?)

The result is significatif, it means that some transitions are prefered.

My problem is that I have other transition tables like this one (with other 
individuals or other conditions)
For example, I also have this one :


trans2<-c(13,7,8,5,16,18,11,8,17)
transitions2<-matrix(trans2, nrow=3, ncol=3, byrow=T)
rownames(transitions2) <- c("High","Low", "Stick")
colnames(transitions2) <- c("High","Low", "Stick")

I want to know if the "prefered" transitions in the table 1 are the same in the 
table 2.
But if I try a khisquare test on those two matrix, R only takes the first one.

How can I compare those tables
Maybe with another test ?

Thanks in advance !

Kind regards

Lucie S.

[[alternative HTML version deleted]]


[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

Re: [R] R help contingency table

2016-06-20 Thread David L Carlson
You should consult with your adviser or someone at your institution who has 
more experience in statistical analysis than you do. You want to compare the 
matrices, but the row/column labels are different so you may be comparing 
completely different categories.

Technically, you need to convert the two matrices into a single matrix. You can 
do that by converting each into a vector with the c() function. BUT this will 
compare High with High, Medium with Low, and Low with Stick which seems 
inadvisable. 

> rbind(c(transitions1), c(transitions2))
 [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
[1,]   51   12   37   17   21   15   27   13   60
[2,]   135   117   1688   18   17
> chisq.test(rbind(c(transitions1), c(transitions2)))

Pearson's Chi-squared test

data:  rbind(c(transitions1), c(transitions2))
X-squared = 22.411, df = 8, p-value = 0.004208

Warning message:
In chisq.test(rbind(c(transitions1), c(transitions2))) :
  Chi-squared approximation may be incorrect

-
David L Carlson
Department of Anthropology
Texas A University
College Station, TX 77840-4352

-Original Message-
From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Lucie Dupond
Sent: Sunday, June 19, 2016 9:10 PM
To: r-help@r-project.org
Subject: [R] R help contingency table

Hello,
I'm sorry if my question is really basic, but I'm having some troubles with the 
statistics for my thesis, and especially the khi square test and contingency 
tables.

For what I understood, there are two "kinds" of khisquare test, that are quite 
similar :
- Homogeneity, when we have one variable and we want to compare it with a 
theorical distribution
- Independence test, when we have 2 variable and we want to see if they are 
linked

-- -

I'm working on color transitions, with 3 possible factors : � High � , � Medium 
� and � Low �
I want to know if an individual will go preferably from a color � High � to 
another color � High �, more than from a color � High � to a color � Medium � 
(for example)

I have this table :

trans1<-c(51,17,27,12,21,13,37,15,60)
transitions1<-matrix(trans1, nrow=3, ncol=3, byrow=T)
rownames(transitions1) <- c("High"," Medium", "Low")
colnames(transitions1) <- c("High"," Medium", "Low")

The first colomn is showing the first color, and the second is showing the 
second color of the transition

It looks like I'm in the case of an Independence test, in order to see if the 
variable "second color" is linked to the "first color".

So I'm making the test :

chisq.test(transitions1)


(If I understood well, the test on the matrix is the independence  test, and 
the test on the vector trans1 is the homogeneity test ?)

The result is significatif, it means that some transitions are prefered.

My problem is that I have other transition tables like this one (with other 
individuals or other conditions)
For example, I also have this one :


trans2<-c(13,7,8,5,16,18,11,8,17)
transitions2<-matrix(trans2, nrow=3, ncol=3, byrow=T)
rownames(transitions2) <- c("High","Low", "Stick")
colnames(transitions2) <- c("High","Low", "Stick")

I want to know if the "prefered" transitions in the table 1 are the same in the 
table 2.
But if I try a khisquare test on those two matrix, R only takes the first one.

How can I compare those tables
Maybe with another test ?

Thanks in advance !

Kind regards

Lucie S.

[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

Re: [R] R help contingency table

2016-06-20 Thread S Ellison
> The first colomn is showing the first color, and the second is showing the
> second color of the transition
Are you sure?
transitions1 is a 3x3 matrix; it has three columns, not two. 

Could it be that the columns are colour 2 following initial condition given by 
row, or vice versa?

[not that that will help _me_ answer your question, but it may help someone 
else].

S Ellison



***
This email and any attachments are confidential. Any use, copying or
disclosure other than by the intended recipient is unauthorised. If 
you have received this message in error, please notify the sender 
immediately via +44(0)20 8943 7000 or notify postmas...@lgcgroup.com 
and delete this message and any copies from your computer and network. 
LGC Limited. Registered in England 2991879. 
Registered office: Queens Road, Teddington, Middlesex, TW11 0LY, UK
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.


[R] R help contingency table

2016-06-20 Thread Lucie Dupond
Hello,
I'm sorry if my question is really basic, but I'm having some troubles with the 
statistics for my thesis, and especially the khi square test and contingency 
tables.

For what I understood, there are two "kinds" of khisquare test, that are quite 
similar :
- Homogeneity, when we have one variable and we want to compare it with a 
theorical distribution
- Independence test, when we have 2 variable and we want to see if they are 
linked

-- -

I'm working on color transitions, with 3 possible factors : � High � , � Medium 
� and � Low �
I want to know if an individual will go preferably from a color � High � to 
another color � High �, more than from a color � High � to a color � Medium � 
(for example)

I have this table :

trans1<-c(51,17,27,12,21,13,37,15,60)
transitions1<-matrix(trans1, nrow=3, ncol=3, byrow=T)
rownames(transitions1) <- c("High"," Medium", "Low")
colnames(transitions1) <- c("High"," Medium", "Low")

The first colomn is showing the first color, and the second is showing the 
second color of the transition

It looks like I'm in the case of an Independence test, in order to see if the 
variable "second color" is linked to the "first color".

So I'm making the test :

chisq.test(transitions1)


(If I understood well, the test on the matrix is the independence  test, and 
the test on the vector trans1 is the homogeneity test ?)

The result is significatif, it means that some transitions are prefered.

My problem is that I have other transition tables like this one (with other 
individuals or other conditions)
For example, I also have this one :


trans2<-c(13,7,8,5,16,18,11,8,17)
transitions2<-matrix(trans2, nrow=3, ncol=3, byrow=T)
rownames(transitions2) <- c("High","Low", "Stick")
colnames(transitions2) <- c("High","Low", "Stick")

I want to know if the "prefered" transitions in the table 1 are the same in the 
table 2.
But if I try a khisquare test on those two matrix, R only takes the first one.

How can I compare those tables
Maybe with another test ?

Thanks in advance !

Kind regards

Lucie S.

[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.