sted in the
> >>> regression coefficients, why not just use a "raw" polynomial:
> >>>>
> >>>> ------- snip ---
> >>>>
> >>>>> (m1 <- lm(y ~ poly(x, 4, raw=TRUE)))
> >>>>
> >>>> Call:
raw = TRUE)3
>>>> 1 1 1 1
>>> 1
>>>> 2 1 2 4
>>> 8
>>>> 3 1 3 9
>
;>> poly(x, 4, raw = TRUE)4 0.870.96
>> 0.99
>>>poly(x, 4, raw = TRUE)4
>>> poly(x, 4, raw = TRUE)10.87
>>> poly(x, 4, raw = TRUE)20.96
>
ret/39051154#39051154
Cheers
Petr
-Original Message-
From: R-help On Behalf Of Ashim
Kapoor
Sent: Wednesday, November 27, 2019 12:55 PM
To: R Help
Subject: [R] Orthogonal polynomials used by R
Dear All,
I have created a time trend by doing x<-1:93 because I have a time
serie
Hamilton, Ontario, Canada
> > Web: http::/socserv.mcmaster.ca/jfox
> >
> > > On Nov 27, 2019, at 10:17 AM, Ashim Kapoor
> wrote:
> > >
> > > Dear Petr,
> > >
> > > Many thanks for the quick response.
> > >
> > >
be used to evaluate it via the three-term recursion given in
> > Kennedy & Gentle (1980, pp. 343-4), and used in the ‘predict’ part
> > of the code.
> >
> > I don't have access to the mentioned book.
> >
> > Out of curiosity, what is the name of the
e one is usually not interested in the individual coefficients of
>> a
>> > polynomial there usually isn't a reason to prefer one parametrization to
>> > the other on the grounds of interpretability, so why do you need to
>> > interpret the regression equation?
>> >
>>
ikipedia.org/wiki/Discrete_orthogonal_polynomials
> > >
> > > Also I read in ?poly:-
> > > The orthogonal polynomial is summarized by the coefficients, which
> > > can be used to evaluate it via the three-term recursion given in
> > >
tioned book.
> >
> > Out of curiosity, what is the name of the discrete orthogonal polynomial
> > used by R ?
> > What discrete measure is it orthogonal with respect to ?
> >
> > Many thanks,
> > Ashim
> >
> >
> >
> >
> > On Wed, No
> <https://stackoverflow.com/questions/39031172/how-poly-generates-orthogonal-polynomials-how-to-understand-the-coefs-ret/39051154#39051154>
>>
>> Cheers
>> Petr
>>
>>> -Original Message-
>>> From: R-help On Behalf Of Ashim Kapoor
>>&g
: Re: [R] Orthogonal polynomials used by R
Dear Petr,
Many thanks for the quick response.
I also read this:-
https://en.wikipedia.org/wiki/Discrete_orthogonal_polynomials
Also I read in ?poly:-
The orthogonal polynomial is summarized by the coefficients, which
can be used to evaluate
low.com/questions/39031172/how-poly-generates-orthogonal-polynomials-how-to-understand-the-coefs-ret/39051154#39051154>
>
> Cheers
> Petr
>
> > -Original Message-
> > From: R-help On Behalf Of Ashim Kapoor
> > Sent: Wednesday, November 27, 2019 12:55 PM
&g
November 27, 2019 12:55 PM
> To: R Help
> Subject: [R] Orthogonal polynomials used by R
>
> Dear All,
>
> I have created a time trend by doing x<-1:93 because I have a time series
> with 93 data points. Next I did :-
>
> y = lm(series ~ poly(x,4))$residuals
>
Dear All,
I have created a time trend by doing x<-1:93 because I have a time series
with 93 data points. Next I did :-
y = lm(series ~ poly(x,4))$residuals
to detrend series.
I choose this 4 as the order of my polynomial using cross validation/
checking the absence of trend in the residuals so
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