Displaying 15 results from an estimated 15 matches similar to: "trouble getting table of coeffs with quantreg with fixed effects"
2008 Dec 17
0
OFF topic testing for positive coeffs
Dear all,
This is off-topic,
however I hope someone can give me useful suggestion..
Given the regression model
y = b0 + b1*x + e
I am interested in testing for positive coeffs, namely
H0: b0>0 AND b1>0
H1: b0,b1 unconstrained
It is simple to estimate the model under H0 and H1 (there are several
suggestions on the Rlist about estimation but nothing about testing..)
perform a likelihood
2001 Oct 12
2
lr with positive coeffs
Is there any way in R to do a linear regression with positive
coefficients only?
Thanks for any help!
Sandor Lehoczky
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2009 Nov 29
1
How to force regression coeffs for some values in a categorical variable
Hi,
I am a new R user. I am using it develop regression models with categorical
variables.
Is there a way to force some regression coefficients to be zero for some of
the values in a categorical variable (with 12 factor levels)?
I am recoding the values to the default value (1st in the order of dummy's).
But I am not sure if this is the correct approach if I want to force
coefficients to be
2012 May 04
1
Correct Interpretation of survreg() coeffs
Am I correct in assuming that the output below essentially translates to
"Males have a mean time that is significantly lower than Females"? Is this
the correct way to interpret the fact that the coefficient is negative?
Assume the variale sex is treated as a factor with Female =0 and Male=1.
survmodel<-survreg(survobj~sex,data=data1, dist="weibull")
2015 Apr 18
0
"keep qlp coeff precision such that only 32-bit math is required"
Brian Willoughby wrote:
> Ok, I just did a comparison of 1.2.1 with 1.3.2, and the change you're
> suggesting was already there before. So, now the question becomes: why
> was the code changed in the first place?
There should be some indication of why in the git history.
Erik
--
----------------------------------------------------------------------
Erik de Castro Lopo
2015 Apr 22
2
"keep qlp coeff precision such that only 32-bit math is required"
Martijn van Beurden wrote:
> Yes, but that MAX value is used to loop over the
> qlp_coeff_precision values between MIN and MAX. So, if the
> qlp_coeff_precision value is limited in the loop but MAX is not
> limited, the loop does the exact same thing multiple times: a
> waste of time. Therefore, only the MAX should be limited.
>
> I don't think the logic is needed
2015 Apr 19
2
"keep qlp coeff precision such that only 32-bit math is required"
Martijn van Beurden wrote:
> Yes, indeed. I removed the 17-bits part because I just matched
> the code in evaluate_lpc_subframe_ with the process_subframe_
> code. It appears it only makes sense that those two pieces code
> are the same.
A bit of history:
1) The conditional "if(subframe_bps <= 16)" was added to evaluate_lpc_subframe_()
in the commit
2015 Apr 18
2
"keep qlp coeff precision such that only 32-bit math is required"
Erik de Castro Lopo wrote:
> There should be some indication of why in the git history.
http://git.xiph.org/?p=flac.git;a=commitdiff;h=27846708fe6271e5e3965a4bbad99baa1ca24c49
Now I remember a discussion about a bug in -p switch: the old code substracts
lpc_order instead of FLAC__bitmath_ilog2(lpc_order), and this commit fixes this.
It seems that the logic in process_subframe_() and in
2015 Apr 20
2
"keep qlp coeff precision such that only 32-bit math is required"
Martijn van Beurden wrote:
> Or maybe the question is: why is this code in evaluate_lpc_subframe anyway,
> i.e, why is this code duplicated? If process_subframe_ sets the
> qlp_precision for evaluate_lpc_subframe, why should the latter ignore that?
>
> We can only speculate about this, but I think this code has been duplicated
> by accident, and therefore it wasn't changed
2015 Apr 18
2
"keep qlp coeff precision such that only 32-bit math is required"
stream_encoder.c has the following code:
/* try to keep qlp coeff precision such that only 32-bit math is required for decode of <=16bps streams */
if(subframe_bps <= 16) {
...
But FLAC can convert 16-bit input to 17-bit if mid-side coding is used.
So, does it make sense to compare subframe_bps with 17?
(The patch is attached. What do you think about it?)
-------------- next part
2015 Apr 18
2
"keep qlp coeff precision such that only 32-bit math is required"
Ok, I just did a comparison of 1.2.1 with 1.3.2, and the change you're suggesting was already there before. So, now the question becomes: why was the code changed in the first place? Was there a bug that was fixed by changing 17 to 16, or did someone just get overzealous in a code review and thought that 17 was a bad choice? Perhaps 32 bits isn't actually large enough to handle the
2011 Jun 27
1
group interaction in a varying coeff. model (mgcv)
Dear UseRs,
I built varying coefficient models (in mgcv) for two groups separately, with one explanatory and one moderator variable (see the example below).
# -------
# Example:
# ------
# generate moderator variable (can the same for both groups)
modvar <- c(1:1000)
# generate group1 values
x1 <- rnorm(1000)
y1 <- scale(cbind(1,poly(modvar,2))%*%c(1,2,1)*x1 +
rnorm(1000,0,0.3))
#
2009 Aug 24
2
robust method to obtain a correlation coeff?
Hi,
Being a R-newbie I am wondering how to calculate a correlation
coefficient (preferably with an associated p-value) for data like:
> d[,1]
[1] 25.5 25.3 25.1 NA 23.3 21.5 23.8 23.2 24.2 22.7 27.6 24.2 ...
> d[,2]
[1] 0.0 11.1 0.0 NA 0.0 10.1 10.6 9.5 0.0 57.9 0.0 0.0 ...
Apparently corr(d) from the boot-library fails with NAs in the data,
also cor.test cannot cope with a
2012 Jul 03
0
need help EM algorithm to find MLE of coeff in mixed effects model
Dear All,
have a general question about coefficients estimation of the mixed model.
I simulated a very basic model: Y|b=X*\beta+Z*b +\sigma^2* diag(ni);
b follows
N(0,\psi) #i.e. bivariate normal
where b is the latent variable, Z and X are ni*2 design matrices, sigma is
the error variance,
Y are longitudinal data, i.e. there are ni
2012 Jul 03
2
EM algorithm to find MLE of coeff in mixed effects model
I have a general question about coefficients estimation of the mixed model.
I simulated a very basic model: Y|b=X*\beta+Z*b +\sigma^2* diag(ni);
b follows
N(0,\psi) #i.e. bivariate normal
where b is the latent variable, Z and X are ni*2 design matrices, sigma is
the error variance,
Y are longitudinal data, i.e. there are ni