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rezvan hatami

2016-Jun-26 10:23 UTC

[R] How I can calculate the value of response variable

?How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?


Cheers
Rezvan Hatami
	[[alternative HTML version deleted]]

David Winsemius

2016-Jun-26 15:20 UTC

head link

[R] How I can calculate the value of response variable

> On Jun 26, 2016, at 3:23 AM, rezvan hatami via R-help <r-help at
r-project.org> wrote:
> 
>  How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?
> 
   You should explain in more detail why the answer to this question is not just
the `lm` function. See:

?lm
?predict.lm

    That would deliver (after suitable invocation of the `predict` function) not
be the "value of the response variable" (since that would just be the
values in your data), but rather the conditional expectation of the response
variable given the values of the predictors.

> 
> Cheers
> Rezvan Hatami
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at 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.
David Winsemius
Alameda, CA, USA

Jeff Newmiller

2016-Jun-26 15:22 UTC

head link

[R] How I can calculate the value of response variable

Can you provide an example of what you mean?  This is not a statistical theory
forum, so you should be able to describe the calculation clearly if you want
help translating it into R.

Also, read the Posting Guide, which among other things warns you that this is a
plain text mailing list so your HTML email is going to be damaged and we may not
be able to understand your question if you don't post plain text.
-- 
Sent from my phone. Please excuse my brevity.

On June 26, 2016 3:23:19 AM PDT, rezvan hatami via R-help <r-help at
r-project.org> wrote:>?How I can calculate the value of response variable in a linear model
>of a matrix of several variables?Can somebody please answer me?
>
>
>Cheers
>Rezvan Hatami
>	[[alternative HTML version deleted]]
>
>______________________________________________
>R-help at 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.

Jim Lemon

2016-Jun-26 22:07 UTC

head link

[R] How I can calculate the value of response variable

Hi Rezvan,
I'll take a guess that you have been presented with a matrix of
coefficients. You probably know that a linear model is going to look
something like this:

Y = ax1 + bx2 + cx3 ...

So I will further guess that you want to infer a distribution of Y
(the response variable) from more than one set of coefficients. If my
guesses are correct, then you should be able to send an example that
shows what you have and what you want to get.

Jim

On Sun, Jun 26, 2016 at 8:23 PM, rezvan hatami via R-help
<r-help at r-project.org> wrote:>  How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?
>
>
> Cheers
> Rezvan Hatami
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.

rezvan hatami

2016-Jun-27 00:22 UTC

head link

[R] Fw: How I can calculate the value of response variable

----- Forwarded Message -----
 From: rezvan hatami <rezvan.hatami_iut at yahoo.com>
 To: David Winsemius <dwinsemius at comcast.net> 
 Sent: Monday, 27 June 2016, 9:44
 Subject: Re: [R] How I can calculate the value of response variable
   
Dear DavidThank you for your answer. My equation is:
nitrate=0.9*fertilizer-0.02*flowrate+0.5*rain
my matrix:
| season | site | nitrate | fertilizer1 | flow rate |
| spring | site1 | 0.2 | 2 | 1 |
| spring | site2 | 1.2 | 3 | 1 |
| spring | site3 | 2.2 | 5 | 2 |
| summer | site1 | 3.2 | 1 | 2 |
| summer | site2 | 4.2 | 2 | 2 |
| summer | site3 | 5.2 | 3 | 2 |
| fall | site1 | 6.2 | 4 | 3 |
| fall | site2 | 7.2 | 5 | 3 |
| fall | site3 | 8.2 | 6 | 3 |
| winter | site1 | 9.2 | 4 | 4 |
| winter | site2 | 10.2 | 8 | 4 |
| winter | site3 | 11.2 | 9 | 4 |


I would like to know, what will be the values for variable "nitrate"
if I divide the values of fertilizer by half and change the equation to:
nitrate=0.9*fertilizer2-0.02*flowrate+0.5*rain

in a matrix like:

| season | site | nitrate | fertilizer2 | flow rate |
| spring | site1 | 0.2 | 1 | 1 |
| spring | site2 | 1.2 | 1.5 | 1 |
| spring | site3 | 2.2 | 2.5 | 2 |
| summer | site1 | 3.2 | 0.5 | 2 |
| summer | site2 | 4.2 | 1 | 2 |
| summer | site3 | 5.2 | 1.5 | 2 |
| fall | site1 | 6.2 | 2 | 3 |
| fall | site2 | 7.2 | 2.5 | 3 |
| fall | site3 | 8.2 | 3 | 3 |
| winter | site1 | 9.2 | 2 | 4 |
| winter | site2 | 10.2 | 4 | 4 |
| winter | site3 | 11.2 | 4.5 | 4 |


Would you please tell me how I can do this in R?
Cheers
Rezvan
      From: David Winsemius <dwinsemius at comcast.net>
 To: rezvan hatami <rezvan.hatami_iut at yahoo.com> 
Cc: "r-help at r-project.org" <r-help at r-project.org>
 Sent: Monday, 27 June 2016, 1:20
 Subject: Re: [R] How I can calculate the value of response variable
  
> On Jun 26, 2016, at 3:23 AM, rezvan hatami via R-help <r-help at
r-project.org> wrote:
> 
>? How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?
> 
? You should explain in more detail why the answer to this question is not just
the `lm` function. See:

?lm
?predict.lm

? ? That would deliver (after suitable invocation of the `predict` function) not
be the "value of the response variable" (since that would just be the
values in your data), but rather the conditional expectation of the response
variable given the values of the predictors.

> 
> Cheers
> Rezvan Hatami
> ??? [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at 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.
David Winsemius
Alameda, CA, USA


   

  
	[[alternative HTML version deleted]]

Jim Lemon

2016-Jun-27 00:28 UTC

head link

[R] How I can calculate the value of response variable

Hi Rezvan,
This looks like a simple problem of solving linear equations (and very much
like a homework exercise). Therefore I won't actually give you the answer,
but suggest the steps for the solution. First you have to get the data into
R, so here is one way:

rhdat<-read.table(text="season,site,nitrate,fertilizer1,flowrate
spring,site1,0.2,2,1
spring,site2,1.2,3,1
spring,site3,2.2,5,2
summer,site1,3.2,1,2
summer,site2,4.2,2,2
summer,site3,5.2,3,2
fall,site1,6.2,4,3
fall,site2,7.2,5,3
fall,site3,8.2,6,3
winter,site1,9.2,4,4
winter,site2,10.2,8,4
winter,site3,11.2,9,4",sep=",",header=TRUE)

You now have a data frame (rhdat) containing the values in your table.

1) calculate values for rain, which are missing from the table, e.g.

rhdat$rain<-2*(rhdat$nitrate-0.9*rhdat$fertilizer+0.02*rhdat$flowrate)

the above is an R expression to calculate the values for rain.

2) You may want explicitly calculate new values for rhdat$fertilizer, and
you have indicated that you already know how to do that. The above should
give you enough information about R syntax to translate the simple equation.

3) Now calculate new values for nitrate based on the equation you supplied,
but substituting the calculated values for rain and the modified values for
fertilizer.

Jim


On Mon, Jun 27, 2016 at 9:43 AM, rezvan hatami <rezvan.hatami_iut at
yahoo.com>
wrote:
> Hi Jim
> Thank you for your answer. nitrate=0.9*fertilizer-0.02*flowrate+0.5*rain
>
> my matrix:
> season site nitrate fertilizer1 flow rate
> spring site1 0.2 2 1
> spring site2 1.2 3 1
> spring site3 2.2 5 2
> summer site1 3.2 1 2
> summer site2 4.2 2 2
> summer site3 5.2 3 2
> fall site1 6.2 4 3
> fall site2 7.2 5 3
> fall site3 8.2 6 3
> winter site1 9.2 4 4
> winter site2 10.2 8 4
> winter site3 11.2 9 4
>
> I would like to know, what will be the values for variable
"nitrate" if I
> divide the values of fertilizer by half and change the equation to:
>
> nitrate=0.9*fertilizer2-0.02*flowrate+0.5*rain
>
> in a matrix like:
>
> season site nitrate fertilizer2 flow rate
> spring site1 0.2 1 1
> spring site2 1.2 1.5 1
> spring site3 2.2 2.5 2
> summer site1 3.2 0.5 2
> summer site2 4.2 1 2
> summer site3 5.2 1.5 2
> fall site1 6.2 2 3
> fall site2 7.2 2.5 3
> fall site3 8.2 3 3
> winter site1 9.2 2 4
> winter site2 10.2 4 4
> winter site3 11.2 4.5 4
> Would you please tell me how I can do this in R?
>
> Cheers
>
> Rezvan
>
>
> ------------------------------
> *From:* Jim Lemon <drjimlemon at gmail.com>
> *To:* rezvan hatami <rezvan.hatami_iut at yahoo.com>; r-help mailing
list <
> r-help at r-project.org>
> *Sent:* Monday, 27 June 2016, 8:07
> *Subject:* Re: [R] How I can calculate the value of response variable
>
> Hi Rezvan,
> I'll take a guess that you have been presented with a matrix of
> coefficients. You probably know that a linear model is going to look
> something like this:
>
> Y = ax1 + bx2 + cx3 ...
>
> So I will further guess that you want to infer a distribution of Y
> (the response variable) from more than one set of coefficients. If my
> guesses are correct, then you should be able to send an example that
> shows what you have and what you want to get.
>
> Jim
>
>
> On Sun, Jun 26, 2016 at 8:23 PM, rezvan hatami via R-help
> <r-help at r-project.org> wrote:
> >  How I can calculate the value of response variable in a linear model
of
> a matrix of several variables?Can somebody please answer me?
> >
> >
> > Cheers
> > Rezvan Hatami
>
> >        [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help at 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
> <http://www.r-project.org/posting-guide.html>
> > and provide commented, minimal, self-contained, reproducible code.
>
>
>
>
	[[alternative HTML version deleted]]

Bert Gunter

2016-Jun-27 00:34 UTC

head link

[R] Fw: How I can calculate the value of response variable

Is this homework? This list tries to enforce  a no homework policy...

If not, it looks to me as if you have made no effort to learn R nor
have you read and followed the posting guide. We generally expect
posters to have made reasonable efforts to do both and demonstrate
what they have tried and how it has failed.

Cheers,
Bert Gunter





Bert Gunter

"The trouble with having an open mind is that people keep coming along
and sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )


On Sun, Jun 26, 2016 at 5:22 PM, rezvan hatami via R-help
<r-help at r-project.org> wrote:>
>
>
> ----- Forwarded Message -----
>  From: rezvan hatami <rezvan.hatami_iut at yahoo.com>
>  To: David Winsemius <dwinsemius at comcast.net>
>  Sent: Monday, 27 June 2016, 9:44
>  Subject: Re: [R] How I can calculate the value of response variable
>
> Dear DavidThank you for your answer. My equation is:
> nitrate=0.9*fertilizer-0.02*flowrate+0.5*rain
> my matrix:
> | season | site | nitrate | fertilizer1 | flow rate |
> | spring | site1 | 0.2 | 2 | 1 |
> | spring | site2 | 1.2 | 3 | 1 |
> | spring | site3 | 2.2 | 5 | 2 |
> | summer | site1 | 3.2 | 1 | 2 |
> | summer | site2 | 4.2 | 2 | 2 |
> | summer | site3 | 5.2 | 3 | 2 |
> | fall | site1 | 6.2 | 4 | 3 |
> | fall | site2 | 7.2 | 5 | 3 |
> | fall | site3 | 8.2 | 6 | 3 |
> | winter | site1 | 9.2 | 4 | 4 |
> | winter | site2 | 10.2 | 8 | 4 |
> | winter | site3 | 11.2 | 9 | 4 |
>
>
> I would like to know, what will be the values for variable
"nitrate" if I divide the values of fertilizer by half and change the
equation to:
> nitrate=0.9*fertilizer2-0.02*flowrate+0.5*rain
>
> in a matrix like:
>
> | season | site | nitrate | fertilizer2 | flow rate |
> | spring | site1 | 0.2 | 1 | 1 |
> | spring | site2 | 1.2 | 1.5 | 1 |
> | spring | site3 | 2.2 | 2.5 | 2 |
> | summer | site1 | 3.2 | 0.5 | 2 |
> | summer | site2 | 4.2 | 1 | 2 |
> | summer | site3 | 5.2 | 1.5 | 2 |
> | fall | site1 | 6.2 | 2 | 3 |
> | fall | site2 | 7.2 | 2.5 | 3 |
> | fall | site3 | 8.2 | 3 | 3 |
> | winter | site1 | 9.2 | 2 | 4 |
> | winter | site2 | 10.2 | 4 | 4 |
> | winter | site3 | 11.2 | 4.5 | 4 |
>
>
> Would you please tell me how I can do this in R?
> Cheers
> Rezvan
>       From: David Winsemius <dwinsemius at comcast.net>
>  To: rezvan hatami <rezvan.hatami_iut at yahoo.com>
> Cc: "r-help at r-project.org" <r-help at r-project.org>
>  Sent: Monday, 27 June 2016, 1:20
>  Subject: Re: [R] How I can calculate the value of response variable
>
>
>> On Jun 26, 2016, at 3:23 AM, rezvan hatami via R-help <r-help at
r-project.org> wrote:
>>
>>  How I can calculate the value of response variable in a linear model
of a matrix of several variables?Can somebody please answer me?
>>
>
>   You should explain in more detail why the answer to this question is not
just the `lm` function. See:
>
> ?lm
> ?predict.lm
>
>     That would deliver (after suitable invocation of the `predict`
function) not be the "value of the response variable" (since that
would just be the values in your data), but rather the conditional expectation
of the response variable given the values of the predictors.
>
>
>>
>> Cheers
>> Rezvan Hatami
>>     [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at 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.
>
> David Winsemius
> Alameda, CA, USA
>
>
>
>
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.

rezvan hatami

2016-Jun-27 00:57 UTC

head link

[R] How I can calculate the value of response variable

Hi Jim
Thank you for your answer. This is not a homework exercise ;). I amde it simple.
Actually I have a matrix of 100 variables. I made it simple so that I can
explain what I need to do. They are not my data and I made them up. I know how
to change the amount of fertilizer but I was not sure what function I need to
use for this. Thank you for calculating the rain, but it wasn't a part of my
question.
Cheers

      From: Jim Lemon <drjimlemon at gmail.com>
 To: rezvan hatami <rezvan.hatami_iut at yahoo.com>; r-help mailing list
<r-help at r-project.org>
 Sent: Monday, 27 June 2016, 10:28
 Subject: Re: [R] How I can calculate the value of response variable

Hi Rezvan,This looks like a simple problem of solving linear equations (and very
much like a homework exercise). Therefore I won't actually give you the
answer, but suggest the steps for the solution. First you have to get the data
into R, so here is one way:
rhdat<-read.table(text="season,site,nitrate,fertilizer1,flowratespring,site1,0.2,2,1spring,site2,1.2,3,1spring,site3,2.2,5,2summer,site1,3.2,1,2summer,site2,4.2,2,2summer,site3,5.2,3,2fall,site1,6.2,4,3fall,site2,7.2,5,3fall,site3,8.2,6,3winter,site1,9.2,4,4winter,site2,10.2,8,4winter,site3,11.2,9,4",sep=",",header=TRUE)
You now have a data frame (rhdat) containing the values in your table.
1) calculate values for rain, which are missing from the table, e.g.
rhdat$rain<-2*(rhdat$nitrate-0.9*rhdat$fertilizer+0.02*rhdat$flowrate)
the above is an R expression to calculate the values for rain.
2) You may want explicitly calculate new values for rhdat$fertilizer, and you
have indicated that you already know how to do that. The above should give you
enough information about R syntax to translate the simple equation.
3) Now calculate new values for nitrate based on the equation you supplied, but
substituting the calculated values for rain and the modified values for
fertilizer.
Jim

On Mon, Jun 27, 2016 at 9:43 AM, rezvan hatami <rezvan.hatami_iut at
yahoo.com> wrote:

Hi JimThank you for your answer. nitrate=0.9*fertilizer-0.02*flowrate+0.5*rain
my matrix:
| season | site | nitrate | fertilizer1 | flow rate |
| spring | site1 | 0.2 | 2 | 1 |
| spring | site2 | 1.2 | 3 | 1 |
| spring | site3 | 2.2 | 5 | 2 |
| summer | site1 | 3.2 | 1 | 2 |
| summer | site2 | 4.2 | 2 | 2 |
| summer | site3 | 5.2 | 3 | 2 |
| fall | site1 | 6.2 | 4 | 3 |
| fall | site2 | 7.2 | 5 | 3 |
| fall | site3 | 8.2 | 6 | 3 |
| winter | site1 | 9.2 | 4 | 4 |
| winter | site2 | 10.2 | 8 | 4 |
| winter | site3 | 11.2 | 9 | 4 |

I would like to know, what will be the values for variable "nitrate"
if I divide the values of fertilizer by half and change the equation to:
nitrate=0.9*fertilizer2-0.02*flowrate+0.5*rain

in a matrix like:

| season | site | nitrate | fertilizer2 | flow rate |
| spring | site1 | 0.2 | 1 | 1 |
| spring | site2 | 1.2 | 1.5 | 1 |
| spring | site3 | 2.2 | 2.5 | 2 |
| summer | site1 | 3.2 | 0.5 | 2 |
| summer | site2 | 4.2 | 1 | 2 |
| summer | site3 | 5.2 | 1.5 | 2 |
| fall | site1 | 6.2 | 2 | 3 |
| fall | site2 | 7.2 | 2.5 | 3 |
| fall | site3 | 8.2 | 3 | 3 |
| winter | site1 | 9.2 | 2 | 4 |
| winter | site2 | 10.2 | 4 | 4 |
| winter | site3 | 11.2 | 4.5 | 4 |

Would you please tell me how I can do this in R?
Cheers
Rezvan

      From: Jim Lemon <drjimlemon at gmail.com>
 To: rezvan hatami <rezvan.hatami_iut at yahoo.com>; r-help mailing list
<r-help at r-project.org>
 Sent: Monday, 27 June 2016, 8:07
 Subject: Re: [R] How I can calculate the value of response variable

Hi Rezvan,
I'll take a guess that you have been presented with a matrix of
coefficients. You probably know that a linear model is going to look
something like this:

Y = ax1 + bx2 + cx3 ...

So I will further guess that you want to infer a distribution of Y
(the response variable) from more than one set of coefficients. If my
guesses are correct, then you should be able to send an example that
shows what you have and what you want to get.

Jim

On Sun, Jun 26, 2016 at 8:23 PM, rezvan hatami via R-help
<r-help at r-project.org> wrote:>? How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?
>
>
> Cheers
> Rezvan Hatami
>? ? ? ? [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.

	[[alternative HTML version deleted]]

rezvan hatami

2016-Jun-27 01:15 UTC

head link

[R] How I can calculate the value of response variable

For the sake of simplicity, I use my example to explain what I have written:

nutrient<-lm(nitrate~0.9*fertilizer-0.02*flowrate+0.5*rain)

datafram=data1

Change the value of fertelizer--??datafram=data2

predict(lm(nitrate~0.9*fertilizer2-0.02*flowrate+0.5*rain), datafram=data2

Is that better now?

      From: Jim Lemon <drjimlemon at gmail.com>
 To: rezvan hatami <rezvan.hatami_iut at yahoo.com>; r-help mailing list
<r-help at r-project.org>
 Sent: Monday, 27 June 2016, 10:28
 Subject: Re: [R] How I can calculate the value of response variable

Hi Rezvan,This looks like a simple problem of solving linear equations (and very
much like a homework exercise). Therefore I won't actually give you the
answer, but suggest the steps for the solution. First you have to get the data
into R, so here is one way:
rhdat<-read.table(text="season,site,nitrate,fertilizer1,flowratespring,site1,0.2,2,1spring,site2,1.2,3,1spring,site3,2.2,5,2summer,site1,3.2,1,2summer,site2,4.2,2,2summer,site3,5.2,3,2fall,site1,6.2,4,3fall,site2,7.2,5,3fall,site3,8.2,6,3winter,site1,9.2,4,4winter,site2,10.2,8,4winter,site3,11.2,9,4",sep=",",header=TRUE)
You now have a data frame (rhdat) containing the values in your table.
1) calculate values for rain, which are missing from the table, e.g.
rhdat$rain<-2*(rhdat$nitrate-0.9*rhdat$fertilizer+0.02*rhdat$flowrate)
the above is an R expression to calculate the values for rain.
2) You may want explicitly calculate new values for rhdat$fertilizer, and you
have indicated that you already know how to do that. The above should give you
enough information about R syntax to translate the simple equation.
3) Now calculate new values for nitrate based on the equation you supplied, but
substituting the calculated values for rain and the modified values for
fertilizer.
Jim

On Mon, Jun 27, 2016 at 9:43 AM, rezvan hatami <rezvan.hatami_iut at
yahoo.com> wrote:

Hi JimThank you for your answer. nitrate=0.9*fertilizer-0.02*flowrate+0.5*rain
my matrix:
| season | site | nitrate | fertilizer1 | flow rate |
| spring | site1 | 0.2 | 2 | 1 |
| spring | site2 | 1.2 | 3 | 1 |
| spring | site3 | 2.2 | 5 | 2 |
| summer | site1 | 3.2 | 1 | 2 |
| summer | site2 | 4.2 | 2 | 2 |
| summer | site3 | 5.2 | 3 | 2 |
| fall | site1 | 6.2 | 4 | 3 |
| fall | site2 | 7.2 | 5 | 3 |
| fall | site3 | 8.2 | 6 | 3 |
| winter | site1 | 9.2 | 4 | 4 |
| winter | site2 | 10.2 | 8 | 4 |
| winter | site3 | 11.2 | 9 | 4 |

I would like to know, what will be the values for variable "nitrate"
if I divide the values of fertilizer by half and change the equation to:
nitrate=0.9*fertilizer2-0.02*flowrate+0.5*rain

in a matrix like:

| season | site | nitrate | fertilizer2 | flow rate |
| spring | site1 | 0.2 | 1 | 1 |
| spring | site2 | 1.2 | 1.5 | 1 |
| spring | site3 | 2.2 | 2.5 | 2 |
| summer | site1 | 3.2 | 0.5 | 2 |
| summer | site2 | 4.2 | 1 | 2 |
| summer | site3 | 5.2 | 1.5 | 2 |
| fall | site1 | 6.2 | 2 | 3 |
| fall | site2 | 7.2 | 2.5 | 3 |
| fall | site3 | 8.2 | 3 | 3 |
| winter | site1 | 9.2 | 2 | 4 |
| winter | site2 | 10.2 | 4 | 4 |
| winter | site3 | 11.2 | 4.5 | 4 |

Would you please tell me how I can do this in R?
Cheers
Rezvan

      From: Jim Lemon <drjimlemon at gmail.com>
 To: rezvan hatami <rezvan.hatami_iut at yahoo.com>; r-help mailing list
<r-help at r-project.org>
 Sent: Monday, 27 June 2016, 8:07
 Subject: Re: [R] How I can calculate the value of response variable

Hi Rezvan,
I'll take a guess that you have been presented with a matrix of
coefficients. You probably know that a linear model is going to look
something like this:

Y = ax1 + bx2 + cx3 ...

So I will further guess that you want to infer a distribution of Y
(the response variable) from more than one set of coefficients. If my
guesses are correct, then you should be able to send an example that
shows what you have and what you want to get.

Jim

On Sun, Jun 26, 2016 at 8:23 PM, rezvan hatami via R-help
<r-help at r-project.org> wrote:>? How I can calculate the value of response variable in a linear model of a
matrix of several variables?Can somebody please answer me?
>
>
> Cheers
> Rezvan Hatami
>? ? ? ? [[alternative HTML version deleted]]
>
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R help - Jun 2016 - How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] Fw: How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] Fw: How I can calculate the value of response variable

[R] How I can calculate the value of response variable

[R] How I can calculate the value of response variable