Re: [R] How to represent the effect of one covariate on regression results?

2020-09-15 Thread Ana Marija
Hi David,

thanks for the useful insight I did of course wrote to plink user
group but no answer there. I guess they are more concerned about how
to run commands with plink as oppose to interpret results.

What I can tell about my cohort is that about 80% of cases had Type 2
diabetes while about 8% had Type 1. (my TD covariate is reference for
the type of diabetes) In the attach is the description of the data.

Cheers,
Ana

On Tue, Sep 15, 2020 at 7:59 PM David Winsemius  wrote:
>
>
> On 9/15/20 8:57 AM, Ana Marija wrote:
> > Hi Abby and David,
> >
> > Thanks for the useful tips! I will check those.
> >
> > I completed the regression analysis in plink (as R would be very slow
> > for my sample size) but as I mentioned I need to determine the
> > influence of a specific covariate in my results and Plink is of no
> > help there.
> >
> > I did Pearson correlation analysis for P values which I got in
> > regression with and without my covariate of interest and I got this:
> >
> >> cor.test(tt$P_TD, tt$P_noTD, method = "pearson", conf.level = 0.95)
> >  Pearson's product-moment correlation
> >
> > data:  tt$P_TD and tt$P_noTD
> > t = 20.17, df = 283, p-value < 2.2e-16
> > alternative hypothesis: true correlation is not equal to 0
> > 95 percent confidence interval:
> >   0.7156134 0.8117108
> > sample estimates:
> >cor
> > 0.7679493
> >
> > I can see the p values are very correlated in those two instances. Can
> > I conclude that my covariate then doesn't have a huge effect or what
> > kind of conclusion I can draw from that?
>
>
> I do not think it follows from the correlation of p-values that your
> covariate "does not have a huge effect". P-values are not really data,
> although they are random values. A simulation study of this would
> require a much better description of the original dataset. Again, that
> is something that the users of Plink are more likely to be able to
> intuit than are we. I still do not see why this question is not being
> addressed to the users of the software from which you are deriving your
> "data".
>
>
> --
>
> David.
>
> >
> > Thanks for all your help
> > Ana
> >
> >
> >
> > On Tue, Sep 15, 2020 at 1:26 AM David Winsemius  
> > wrote:
> >> There is a user-group for PLINK, easily found by looking at the page you
> >> cited. This is not the correct place to submit such questions.
> >>
> >>
> >> https://groups.google.com/g/plink2-users?pli=1
> >>
> >>
> >> --
> >>
> >> David.
> >>
> >> On 9/14/20 6:29 AM, Ana Marija wrote:
> >>> Hello,
> >>>
> >>> I was running association analysis using --glm genotypic from:
> >>> https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
> >>> sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
> >>> result looks like this:
> >>>
> >>>   #CHROMPOSIDREFALTA1TESTOBS_CTBETA
> >>> SEZ_OR_F_STATPERRCODE
> >>>   10135434303rs11101905GAAADD11863
> >>> -0.1107330.0986981-1.121930.261891.
> >>>   10135434303rs11101905GAADOMDEV11863
> >>> 0.0797970.1110040.7188680.47.
> >>>   10135434303rs11101905GAAsex=Female
> >>> 11863-0.1204040.0536069-2.246050.0247006.
> >>>   10135434303rs11101905GAAage11863
> >>> 0.005245010.003915281.339630.180367.
> >>>   10135434303rs11101905GAAPC111863
> >>> -0.01917790.0166868-1.149280.25044.
> >>>   10135434303rs11101905GAAPC211863
> >>> -0.02699390.0173086-1.559570.118863.
> >>>   10135434303rs11101905GAAPC311863
> >>> 0.01152070.01680760.6854480.493061.
> >>>   10135434303rs11101905GAAPC411863
> >>> 9.57832e-050.01246070.00768680.993867.
> >>>   10135434303rs11101905GAAPC511863
> >>> -0.001910470.00543937-0.351230.725416.
> >>>   10135434303rs11101905GAAPC611863
> >>> -0.01033090.0159879-0.6461720.518168.
> >>>   10135434303rs11101905GAAPC711863
> >>> 0.007909970.01440250.5492070.582863.
> >>>   10135434303rs11101905GAAPC811863
> >>> -0.002056390.0142709-0.1440960.885424.
> >>>   10135434303rs11101905GAAPC911863
> >>> -0.008737710.0057239-1.526530.126878.
> >>>   10135434303rs11101905GAAPC1011863
> >>> 0.01161970.01238260.9383880.348045.
> >>>   10135434303rs11101905GAATD11863
> >>> -0.6700260.0962216-6.963373.32228e-12.
> >>>   10135434303rs11101905GAAarray=Biobank
> >>> 118630.160666

Re: [R] How to represent the effect of one covariate on regression results?

2020-09-15 Thread David Winsemius



On 9/15/20 8:57 AM, Ana Marija wrote:

Hi Abby and David,

Thanks for the useful tips! I will check those.

I completed the regression analysis in plink (as R would be very slow
for my sample size) but as I mentioned I need to determine the
influence of a specific covariate in my results and Plink is of no
help there.

I did Pearson correlation analysis for P values which I got in
regression with and without my covariate of interest and I got this:


cor.test(tt$P_TD, tt$P_noTD, method = "pearson", conf.level = 0.95)

 Pearson's product-moment correlation

data:  tt$P_TD and tt$P_noTD
t = 20.17, df = 283, p-value < 2.2e-16
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
  0.7156134 0.8117108
sample estimates:
   cor
0.7679493

I can see the p values are very correlated in those two instances. Can
I conclude that my covariate then doesn't have a huge effect or what
kind of conclusion I can draw from that?



I do not think it follows from the correlation of p-values that your 
covariate "does not have a huge effect". P-values are not really data, 
although they are random values. A simulation study of this would 
require a much better description of the original dataset. Again, that 
is something that the users of Plink are more likely to be able to 
intuit than are we. I still do not see why this question is not being 
addressed to the users of the software from which you are deriving your 
"data".



--

David.



Thanks for all your help
Ana



On Tue, Sep 15, 2020 at 1:26 AM David Winsemius  wrote:

There is a user-group for PLINK, easily found by looking at the page you
cited. This is not the correct place to submit such questions.


https://groups.google.com/g/plink2-users?pli=1


--

David.

On 9/14/20 6:29 AM, Ana Marija wrote:

Hello,

I was running association analysis using --glm genotypic from:
https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
result looks like this:

  #CHROMPOSIDREFALTA1TESTOBS_CTBETA
SEZ_OR_F_STATPERRCODE
  10135434303rs11101905GAAADD11863
-0.1107330.0986981-1.121930.261891.
  10135434303rs11101905GAADOMDEV11863
0.0797970.1110040.7188680.47.
  10135434303rs11101905GAAsex=Female
11863-0.1204040.0536069-2.246050.0247006.
  10135434303rs11101905GAAage11863
0.005245010.003915281.339630.180367.
  10135434303rs11101905GAAPC111863
-0.01917790.0166868-1.149280.25044.
  10135434303rs11101905GAAPC211863
-0.02699390.0173086-1.559570.118863.
  10135434303rs11101905GAAPC311863
0.01152070.01680760.6854480.493061.
  10135434303rs11101905GAAPC411863
9.57832e-050.01246070.00768680.993867.
  10135434303rs11101905GAAPC511863
-0.001910470.00543937-0.351230.725416.
  10135434303rs11101905GAAPC611863
-0.01033090.0159879-0.6461720.518168.
  10135434303rs11101905GAAPC711863
0.007909970.01440250.5492070.582863.
  10135434303rs11101905GAAPC811863
-0.002056390.0142709-0.1440960.885424.
  10135434303rs11101905GAAPC911863
-0.008737710.0057239-1.526530.126878.
  10135434303rs11101905GAAPC1011863
0.01161970.01238260.9383880.348045.
  10135434303rs11101905GAATD11863
-0.6700260.0962216-6.963373.32228e-12.
  10135434303rs11101905GAAarray=Biobank
118630.1606660.0736312.182050.0291062.
  10135434303rs11101905GAAHBA1C11863
0.02659330.0016875815.75836.0236e-56.
  10135434303rs11101905GAAGENO_2DF11863
NANA0.7265140.483613.

This results is shown just for one ID (rs11101905) there is about 2
million of those in the resulting file.

My question is how do I present/plot the effect of covariate "TD" in
the example it has "P" equal to 3.32228e-12 for all IDs in the
resulting file so that I show how much effect covariate "TD" has on
the analysis. Should I run another regression without covariate "TD"
and than do scatter plot of P values with and without "TD" covariate
or there is a better way to do this from the data I already have?

Thanks
Ana

__
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Re: [R] How to represent the effect of one covariate on regression results?

2020-09-15 Thread Abby Spurdle
> My question is how do I present/plot the effect of covariate "TD" in
> the example it has "P" equal to 3.32228e-12 for all IDs in the
> resulting file so that I show how much effect covariate "TD" has on
> the analysis. Should I run another regression without covariate "TD"

I'll take a second shot in the dark:

There is R^2, and a number of generalizations.
(The most common of which, is probably adjusted R^2).
And there are various other goodness of fit tests.

https://en.wikipedia.org/wiki/Goodness_of_fit
https://en.wikipedia.org/wiki/Coefficient_of_determination

You could fit two models (one with a particular variable included, and
one without), and compare how the statistic changes.

However, I'm probably going to get told off, for going off-topic.
So, unless any further questions are specific to R programming, I
don't think I'm going to contribute further.

Also, I'd recommend you read some notes on statistical modelling, or
consult an expert, or both.
And I suspect there are additional considerations modelling genetic data.

__
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] How to represent the effect of one covariate on regression results?

2020-09-15 Thread Ana Marija
Hi Abby and David,

Thanks for the useful tips! I will check those.

I completed the regression analysis in plink (as R would be very slow
for my sample size) but as I mentioned I need to determine the
influence of a specific covariate in my results and Plink is of no
help there.

I did Pearson correlation analysis for P values which I got in
regression with and without my covariate of interest and I got this:

> cor.test(tt$P_TD, tt$P_noTD, method = "pearson", conf.level = 0.95)

Pearson's product-moment correlation

data:  tt$P_TD and tt$P_noTD
t = 20.17, df = 283, p-value < 2.2e-16
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
 0.7156134 0.8117108
sample estimates:
  cor
0.7679493

I can see the p values are very correlated in those two instances. Can
I conclude that my covariate then doesn't have a huge effect or what
kind of conclusion I can draw from that?

Thanks for all your help
Ana



On Tue, Sep 15, 2020 at 1:26 AM David Winsemius  wrote:
>
> There is a user-group for PLINK, easily found by looking at the page you
> cited. This is not the correct place to submit such questions.
>
>
> https://groups.google.com/g/plink2-users?pli=1
>
>
> --
>
> David.
>
> On 9/14/20 6:29 AM, Ana Marija wrote:
> > Hello,
> >
> > I was running association analysis using --glm genotypic from:
> > https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
> > sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
> > result looks like this:
> >
> >  #CHROMPOSIDREFALTA1TESTOBS_CTBETA
> >SEZ_OR_F_STATPERRCODE
> >  10135434303rs11101905GAAADD11863
> > -0.1107330.0986981-1.121930.261891.
> >  10135434303rs11101905GAADOMDEV11863
> > 0.0797970.1110040.7188680.47.
> >  10135434303rs11101905GAAsex=Female
> > 11863-0.1204040.0536069-2.246050.0247006.
> >  10135434303rs11101905GAAage11863
> > 0.005245010.003915281.339630.180367.
> >  10135434303rs11101905GAAPC111863
> > -0.01917790.0166868-1.149280.25044.
> >  10135434303rs11101905GAAPC211863
> > -0.02699390.0173086-1.559570.118863.
> >  10135434303rs11101905GAAPC311863
> > 0.01152070.01680760.6854480.493061.
> >  10135434303rs11101905GAAPC411863
> > 9.57832e-050.01246070.00768680.993867.
> >  10135434303rs11101905GAAPC511863
> > -0.001910470.00543937-0.351230.725416.
> >  10135434303rs11101905GAAPC611863
> > -0.01033090.0159879-0.6461720.518168.
> >  10135434303rs11101905GAAPC711863
> > 0.007909970.01440250.5492070.582863.
> >  10135434303rs11101905GAAPC811863
> > -0.002056390.0142709-0.1440960.885424.
> >  10135434303rs11101905GAAPC911863
> > -0.008737710.0057239-1.526530.126878.
> >  10135434303rs11101905GAAPC1011863
> > 0.01161970.01238260.9383880.348045.
> >  10135434303rs11101905GAATD11863
> > -0.6700260.0962216-6.963373.32228e-12.
> >  10135434303rs11101905GAAarray=Biobank
> > 118630.1606660.0736312.182050.0291062.
> >  10135434303rs11101905GAAHBA1C11863
> > 0.02659330.0016875815.75836.0236e-56.
> >  10135434303rs11101905GAAGENO_2DF11863
> >NANA0.7265140.483613.
> >
> > This results is shown just for one ID (rs11101905) there is about 2
> > million of those in the resulting file.
> >
> > My question is how do I present/plot the effect of covariate "TD" in
> > the example it has "P" equal to 3.32228e-12 for all IDs in the
> > resulting file so that I show how much effect covariate "TD" has on
> > the analysis. Should I run another regression without covariate "TD"
> > and than do scatter plot of P values with and without "TD" covariate
> > or there is a better way to do this from the data I already have?
> >
> > Thanks
> > Ana
> >
> > __
> > 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.

__
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Re: [R] How to represent the effect of one covariate on regression results?

2020-09-15 Thread David Winsemius
There is a user-group for PLINK, easily found by looking at the page you 
cited. This is not the correct place to submit such questions.



https://groups.google.com/g/plink2-users?pli=1


--

David.

On 9/14/20 6:29 AM, Ana Marija wrote:

Hello,

I was running association analysis using --glm genotypic from:
https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
result looks like this:

 #CHROMPOSIDREFALTA1TESTOBS_CTBETA
   SEZ_OR_F_STATPERRCODE
 10135434303rs11101905GAAADD11863
-0.1107330.0986981-1.121930.261891.
 10135434303rs11101905GAADOMDEV11863
0.0797970.1110040.7188680.47.
 10135434303rs11101905GAAsex=Female
11863-0.1204040.0536069-2.246050.0247006.
 10135434303rs11101905GAAage11863
0.005245010.003915281.339630.180367.
 10135434303rs11101905GAAPC111863
-0.01917790.0166868-1.149280.25044.
 10135434303rs11101905GAAPC211863
-0.02699390.0173086-1.559570.118863.
 10135434303rs11101905GAAPC311863
0.01152070.01680760.6854480.493061.
 10135434303rs11101905GAAPC411863
9.57832e-050.01246070.00768680.993867.
 10135434303rs11101905GAAPC511863
-0.001910470.00543937-0.351230.725416.
 10135434303rs11101905GAAPC611863
-0.01033090.0159879-0.6461720.518168.
 10135434303rs11101905GAAPC711863
0.007909970.01440250.5492070.582863.
 10135434303rs11101905GAAPC811863
-0.002056390.0142709-0.1440960.885424.
 10135434303rs11101905GAAPC911863
-0.008737710.0057239-1.526530.126878.
 10135434303rs11101905GAAPC1011863
0.01161970.01238260.9383880.348045.
 10135434303rs11101905GAATD11863
-0.6700260.0962216-6.963373.32228e-12.
 10135434303rs11101905GAAarray=Biobank
118630.1606660.0736312.182050.0291062.
 10135434303rs11101905GAAHBA1C11863
0.02659330.0016875815.75836.0236e-56.
 10135434303rs11101905GAAGENO_2DF11863
   NANA0.7265140.483613.

This results is shown just for one ID (rs11101905) there is about 2
million of those in the resulting file.

My question is how do I present/plot the effect of covariate "TD" in
the example it has "P" equal to 3.32228e-12 for all IDs in the
resulting file so that I show how much effect covariate "TD" has on
the analysis. Should I run another regression without covariate "TD"
and than do scatter plot of P values with and without "TD" covariate
or there is a better way to do this from the data I already have?

Thanks
Ana

__
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] How to represent the effect of one covariate on regression results?

2020-09-14 Thread Abby Spurdle
I'm wondering if you want one of these:
(1) Plots of "Main Effects".
(2) "Partial Residual Plots".

Search for them, and you should be able to tell if they're what you want.

But a word of warning:

Many people (including many senior statisticians) misinterpret this
kind of information.
Because, it's always the effect of xj on Y, while holding the other
variables *constant*.
That's not as simple as it sounds, and people have a tendency of
disregarding the importance of the second half of that sentence, in
their final interpretations.


P.S.
John Fox, announced a package with support for Regression Diagnostics,
about 11 days ago:
https://stat.ethz.ch/pipermail/r-help/2020-September/468609.html

I'm not sure how relevant it is to your question, but I just glanced
at the vignette, and it's pretty slick...




On Tue, Sep 15, 2020 at 1:30 AM Ana Marija  wrote:
>
> Hello,
>
> I was running association analysis using --glm genotypic from:
> https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
> sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
> result looks like this:
>
> #CHROMPOSIDREFALTA1TESTOBS_CTBETA
>   SEZ_OR_F_STATPERRCODE
> 10135434303rs11101905GAAADD11863
> -0.1107330.0986981-1.121930.261891.
> 10135434303rs11101905GAADOMDEV11863
> 0.0797970.1110040.7188680.47.
> 10135434303rs11101905GAAsex=Female
> 11863-0.1204040.0536069-2.246050.0247006.
> 10135434303rs11101905GAAage11863
> 0.005245010.003915281.339630.180367.
> 10135434303rs11101905GAAPC111863
> -0.01917790.0166868-1.149280.25044.
> 10135434303rs11101905GAAPC211863
> -0.02699390.0173086-1.559570.118863.
> 10135434303rs11101905GAAPC311863
> 0.01152070.01680760.6854480.493061.
> 10135434303rs11101905GAAPC411863
> 9.57832e-050.01246070.00768680.993867.
> 10135434303rs11101905GAAPC511863
> -0.001910470.00543937-0.351230.725416.
> 10135434303rs11101905GAAPC611863
> -0.01033090.0159879-0.6461720.518168.
> 10135434303rs11101905GAAPC711863
> 0.007909970.01440250.5492070.582863.
> 10135434303rs11101905GAAPC811863
> -0.002056390.0142709-0.1440960.885424.
> 10135434303rs11101905GAAPC911863
> -0.008737710.0057239-1.526530.126878.
> 10135434303rs11101905GAAPC1011863
> 0.01161970.01238260.9383880.348045.
> 10135434303rs11101905GAATD11863
> -0.6700260.0962216-6.963373.32228e-12.
> 10135434303rs11101905GAAarray=Biobank
> 118630.1606660.0736312.182050.0291062.
> 10135434303rs11101905GAAHBA1C11863
> 0.02659330.0016875815.75836.0236e-56.
> 10135434303rs11101905GAAGENO_2DF11863
>   NANA0.7265140.483613.
>
> This results is shown just for one ID (rs11101905) there is about 2
> million of those in the resulting file.
>
> My question is how do I present/plot the effect of covariate "TD" in
> the example it has "P" equal to 3.32228e-12 for all IDs in the
> resulting file so that I show how much effect covariate "TD" has on
> the analysis. Should I run another regression without covariate "TD"
> and than do scatter plot of P values with and without "TD" covariate
> or there is a better way to do this from the data I already have?
>
> Thanks
> Ana
>
> __
> 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
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[R] How to represent the effect of one covariate on regression results?

2020-09-14 Thread Ana Marija
Hello,

I was running association analysis using --glm genotypic from:
https://www.cog-genomics.org/plink/2.0/assoc with these covariates:
sex,age,PC1,PC2,PC3,PC4,PC5,PC6,PC7,PC8,PC9,PC10,TD,array,HBA1C. The
result looks like this:

#CHROMPOSIDREFALTA1TESTOBS_CTBETA
  SEZ_OR_F_STATPERRCODE
10135434303rs11101905GAAADD11863
-0.1107330.0986981-1.121930.261891.
10135434303rs11101905GAADOMDEV11863
0.0797970.1110040.7188680.47.
10135434303rs11101905GAAsex=Female
11863-0.1204040.0536069-2.246050.0247006.
10135434303rs11101905GAAage11863
0.005245010.003915281.339630.180367.
10135434303rs11101905GAAPC111863
-0.01917790.0166868-1.149280.25044.
10135434303rs11101905GAAPC211863
-0.02699390.0173086-1.559570.118863.
10135434303rs11101905GAAPC311863
0.01152070.01680760.6854480.493061.
10135434303rs11101905GAAPC411863
9.57832e-050.01246070.00768680.993867.
10135434303rs11101905GAAPC511863
-0.001910470.00543937-0.351230.725416.
10135434303rs11101905GAAPC611863
-0.01033090.0159879-0.6461720.518168.
10135434303rs11101905GAAPC711863
0.007909970.01440250.5492070.582863.
10135434303rs11101905GAAPC811863
-0.002056390.0142709-0.1440960.885424.
10135434303rs11101905GAAPC911863
-0.008737710.0057239-1.526530.126878.
10135434303rs11101905GAAPC1011863
0.01161970.01238260.9383880.348045.
10135434303rs11101905GAATD11863
-0.6700260.0962216-6.963373.32228e-12.
10135434303rs11101905GAAarray=Biobank
118630.1606660.0736312.182050.0291062.
10135434303rs11101905GAAHBA1C11863
0.02659330.0016875815.75836.0236e-56.
10135434303rs11101905GAAGENO_2DF11863
  NANA0.7265140.483613.

This results is shown just for one ID (rs11101905) there is about 2
million of those in the resulting file.

My question is how do I present/plot the effect of covariate "TD" in
the example it has "P" equal to 3.32228e-12 for all IDs in the
resulting file so that I show how much effect covariate "TD" has on
the analysis. Should I run another regression without covariate "TD"
and than do scatter plot of P values with and without "TD" covariate
or there is a better way to do this from the data I already have?

Thanks
Ana

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