Displaying 20 results from an estimated 500 matches similar to: "Testing for weak exogeneity in a SUR ECM"
2013 Oct 19
2
ivreg with fixed effect in R?
I want to estimate the following fixed effect model:
y_i,t = alpha_i + beta_1 x1_t + beta_2 x2_i,tx2_i,t = gamma_i + gamma_1
x1_t + gamma_2 Z1_i + gamma_3 Z2_i
I can use ivreg from AER to do the iv regression.
fm <- ivreg(y_i,t ~ x1_t + x2_i,t | x1_t + Z1_i + Z2_i,
data = DataSet)
But, I'm not sure how can I add the fixed effects.
Thanks!
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2013 Mar 22
1
Integration of vector syntax unknown
Hello,
I'm very new to using R, but I was told it could do what I want. I'm not sure how best to enter the information but here goes...
I'm trying to transfer the following integral into R to solve for ln(gamma_1), on the left, for multiple instances of gamma_i and variable N_i.
gamma_i is, for example, (0, 0.03012048, 0.05000000, 0.19200000, 0.44000000, 0.62566845)
N_i (N_1 or
2006 Sep 18
1
non linear modelling with nls: starting values
Hi,
I'm trying to fit the following model to data using 'nls':
y = alpha_1 * beta_1 * exp(-beta_1 * x) +
alpha_2 * beta_2 * exp(-beta_2 * x)
and the call I've been using is:
nls(y ~ alpha_1 * beta_1 * exp(-beta_1 * x) +
alpha_2 * beta_2 * exp(-beta_2 * x),
start=list(alpha_1=4, alpha_2=2, beta_1=3.5, beta_2=2.5),
trace=TRUE, control=nls.control(maxiter =
2009 Jun 16
1
turning off escape sequences for a string
Hello,
I would like to create a matrix with one of the columns named
$\delta$. I have also created columns $\beta_1$ , $\beta_2$, etc.
However, it seems like \d is an escape sequence which gets
automatically removed. (Using these names such that they work right in
xtable -> latex)
colnames(simpleReg.mat) <- c("$\beta_1$","$SE(\beta_1)$", "$\beta_2$",
2012 Feb 21
0
BHHH algorithm on duration time models for stock prices
I am currently trying to find MLE of a function with four parameters. My codes run well but i don't get the results. I get the following message:
BHHH maximisation
Number of iterations: 0
Return code: 100
Initial value out of range.
I don't know this is so because of the way i have written my loglikelihood or what.
The loglikelihood
LogLik<-function(param){
beta_1<-param[1]
2013 May 28
1
The weak exogeneity test in R for the Error Correction Model?
Hello all,
I would like to carry out a single-equation approach of the Error Correction Model such as
Delta_y(t) = a + b*y(t-1) + c*x1(t-1) + d*x2(t-1) + e*delta_x1(t) + f*delta_x2(t) + epsilon(t)
Where, a, b, c, d, e, f are coefficients to be estimated, y is the dependent variable, and x1, x2 are independent variables.
For the single equation approach of ECM, there is a requirement of the
2018 Feb 16
2
[FORGED] Re: SE for all levels (including reference) of a factor atfer a GLM
On 16/02/18 15:28, Bert Gunter wrote:
> This is really a statistical issue. What do you think the Intercept term
> represents? See ?contrasts.
>
> Cheers,
> Bert
>
>
>
> 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
2012 Oct 04
1
(no subject)
producing a multi-figure plot, i am try to add beta_1, beta_2,.. beta_9 to
ylab using expression or substitution, but cannot work out like
for (i in 1:9){
plot(seq(1/m, 1-1/m, 1/m), beta.q[,i], type="l", col=1,
ylim=range(beta.q),
xlab="quantile", ylab=expresion(beta[i]))
}
any suggestions will be greatly appreciated.
DL
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2005 Dec 29
0
calculating recursive sequences
Hi,
I was trying to repeat the estimation of threshold GARCH models from
the book "Analysis of Financial Time Series" by Ruey S. Tsay, and I
was succesfull, but I had to use "for" loop, which is quite slow. The
loop is necessary, since you need to calculate recursive sequence. Is
there a faster way to do this in R, without using loops?
The model is such:
r_t = \mu + \alpha_2
2012 Oct 27
0
[gam] [mgcv] Question in integrating a eiker-white "sandwich" VCV estimator into GAM
Dear List,
I'm just teaching myself semi-parametric techniques. Apologies in
advance for the long post.
I've got observational data and a longitudinal, semi-parametric model
that I want to fit in GAM (or potentially something equivalent), and I'm
not sure how to do it. I'm posting this to ask whether it is possible
to do what I want to do using "canned" commands
2013 Apr 30
0
Ridge regression
Hi all,
I have run a ridge regression on a data set 'final' as follows:
reg=lm.ridge(final$l~final$lag1+final$lag2+final$g+final$u,
lambda=seq(0,10,0.01))
Then I enter :
select(reg) and it returns: modified HKB estimator is 19.3409
modified L-W estimator is 36.18617
smallest value of GCV at 10
I think it
2011 Aug 19
3
Calculating p-value for 1-tailed test in a linear model
Hello,
I'm having trouble figuring out how to calculate a p-value for a 1-tailed
test of beta_1 in a linear model fit using command lm. My model has only 1
continuous, predictor variable. I want to test the null hypothesis beta_1
is >= 0. I can calculate the p-value for a 2-tailed test using the code
"2*pt(-abs(t-value), df=degrees.freedom)", where t-value and degrees.freedom
2006 Oct 31
2
Put a normal curve on plot
I would like to be able to place a normal distribution surrounding the
predicted values at various places on a plot. Below is some toy code
that creates a scatterplot and plots a regression line through the data.
library(MASS)
mu <- c(0,1)
Sigma <- matrix(c(1,.8,.8,1), ncol=2)
set.seed(123)
x <- mvrnorm(50,mu,Sigma)
plot(x)
abline(lm(x[,2] ~ x[,1]))
Say I want to add a normal
2004 Aug 23
1
Two factor ANOVA with lm()
The following is a data frame
> "jjd" <- structure(list(Observations = c(6.8, 6.6, 5.3, 6.1,
7.5, 7.4, 7.2, 6.5, 7.8, 9.1, 8.8, 9.1), LevelA = structure(c(1,
1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3), .Label = c("A1", "A2",
"A3"), class = "factor"), LevelB = structure(c(1, 1, 2, 2,
1, 1, 2, 2, 1, 1, 2, 2), .Label =
2005 Dec 01
2
Minimizing a Function with three Parameters
Hi,
I'm trying to get maximum likelihood estimates of \alpha, \beta_0 and
\beta_1, this can be achieved by solving the following three equations:
n / \alpha + \sum\limits_{i=1}^{n} ln(\psihat(i)) -
\sum\limits_{i=1}^{n} ( ln(x_i + \psihat(i)) ) = 0
\alpha \sum\limits_{i=1}^{n} 1/(psihat(i)) - (\alpha+1)
\sum\limits_{i=1}^{n} ( 1 / (x_i + \psihat(i)) ) = 0
\alpha \sum\limits_{i=1}^{n} (
2005 Nov 24
1
residuals in logistic regression model
In the logistic regression model, there is no residual
log (pi/(1-pi)) = beta_0 + beta_1*X_1 + .....
But glm model will return
residuals
What is that?
How to understand this? Can we put some residual in the logistic regression
model by replacing pi with pi' (the estimated pi)?
log (pi'/(1-pi')) = beta_0 + beta_1*X_1 + .....+ ei
Thanks!
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2007 Sep 13
1
Problem using xtable on an array
Hi all
I know about producing a minimal example to show my problem. But I'm
having trouble producing a minimal example that displays this
behaviour, so please bear with me to begin with.
Observe: I create an array called model.mat. Some details on this:
> str(model.mat)
num [1:18, 1:4] -0.170 -0.304 -2.617 2.025 -1.610 ...
- attr(*, "dimnames")=List of 2
..$ : chr
2008 May 16
1
SE of difference in fitted probabilities from logistic model.
I am fitting a logistic binomial model of the form
glm(y ~ a*x,family=binomial)
where a is a factor (with 5 levels) and x is a continuous predictor.
To assess how much ``impact'' x has, I want to compare the fitted
success probability
when x = its maximum value with the fitted probability when x = its
mean value.
(The mean and the max are to be taken by level of the factor
2018 Jan 08
1
Switching from Internal DNS to Bind9_DLZ
On 1/2/2018 4:05 PM, Rowland Penny wrote:
> On Tue, 2 Jan 2018 15:52:57 -0500
> lingpanda101 <lingpanda101 at gmail.com> wrote:
>
>> On 1/2/2018 3:37 PM, Rowland Penny wrote:
>>> On Tue, 2 Jan 2018 15:23:18 -0500
>>> lingpanda101 <lingpanda101 at gmail.com> wrote:
>>>
>>>
>>>> Actually it looks as if Bind isn't running.
2006 Aug 09
1
NLS and IV
Hello All,
I'm looking to test a variable in a logit model (glm(...,
binomial(link="logit"))) for exogeneity (endogeneity). At this point I am
planning to try implementing Jeffery Grogger's "A Simple Test for Exogeneity in
Probit, Logit, and Poisson Regression Models", Economic Letters, 1990. To do
this, I need to be able to do an instrumental variables NLS