Displaying 20 results from an estimated 300 matches similar to: "multivariate diagnostics"
2003 Oct 27
4
how to set missing values in R
Hi, there.
Can I ask how to set up missing values in R? Suppose I want to assign the
missing value to the elements in vector which is greater than zero like
this:
x<-c(1,3,-1,0,4);
after the missing value assignment, x becomes (NA,NA,-1,0,NA).
Thanks!
Yulei
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Yulei He
1586 Murfin Ave. Apt 37
Ann Arbor, MI 48105-3135
yuleih at umich.edu
2004 Oct 30
2
(no subject)
Hi, there.
Does anybody know how to plot a smooth density plot for some data
simulated from certain distribution? Thanks.
Yulei
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Yulei He
1586 Murfin Ave. Apt 37
Ann Arbor, MI 48105-3135
yuleih at umich.edu
734-647-0305(H)
734-763-0421(O)
734-763-0427(O)
734-764-8263(fax)
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
2005 Feb 05
1
plot smooth density estimates for bivariate data
Hi, there.
Suppose I have a bivarariate data matrix y1 and y2. I want to plot a 3-D
picture of the estimated density f(y1, y2) against y1 and y2? How can I do
that? Do I use persp() or density()?
Thanks for your help.
Yulei
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Yulei He
1586 Murfin Ave. Apt 37
Ann Arbor, MI 48105-3135
yuleih at umich.edu
734-647-0305(H)
734-763-0421(O)
734-763-0427(O)
2005 Jul 02
1
probability-probability plot
Hi, there.
Is there any function in R to plot the probability-probability plot (PP
plot)? Suppose I am testing some data against normal.
Thanks.
Yulei
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Yulei He
1586 Murfin Ave. Apt 37
Ann Arbor, MI 48105-3135
yuleih at umich.edu
734-647-0305(H)
734-763-0421(O)
734-763-0427(O)
734-764-8263(fax)
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
2004 Nov 17
1
how to estimate conditional density
Hi, there.
Suppose I have a bivariate data set y1 and y2. Can anybody tell me how to
estimate the conditional density of f(y1|y2) and vice versa? Thanks.
Yulei
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Yulei He
1586 Murfin Ave. Apt 37
Ann Arbor, MI 48105-3135
yuleih at umich.edu
734-647-0305(H)
734-763-0421(O)
734-763-0427(O)
734-764-8263(fax)
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
2005 Sep 26
2
questions about boxplots
Hi, there.
I have two questions about using R to create boxplots.
1. The function boxplot() plots the outliers. How can I label the exact
values arount these outlier points? Does R have an option allow me to
do that?
2. How can I put two boxplots in one x-y axis?
Thanks.
Yulei
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Yulei He
276 Grove St. Apt 3
Newton, MA 02466
617-796-7834(H)
2004 Jul 16
0
for loops in Gibbs sampler
Dear all:
I am using R to do multiple imputation for longitudinal data set. The
Gibbs chain basically requires draw posterior distribution of model
parameters, including the random effects. The multiple imputation requires
several independent Gibbs chains. So my program structure is like:
for (chain in 1:5)
{
# perform Gibbs sampling...
for (row in 1:row.no)
{
b.row=some function # draw
2008 Jun 26
2
constructing arbitrary (positive definite) covariance matrix
Dear list,
I am trying to use the 'mvrnorm' function from the MASS package for
simulating multivariate Gaussian data with given covariance matrix.
The diagonal elements of my covariance matrix should be the same,
i.e., all variables have the same marginal variance. Also all
correlations between all pair of variables should be identical, but
could be any value in [-1,1]. The problem I am
2007 Nov 17
1
save p-value in mshapiro.test(mvnormtest)
Dear all,
I want to save the p-value from mshapiro.test(mvnormtest). But mshapiro.test(mvnormtest) gives a list with class "htest" containing statistic, p.value, method and data.name as a whole.
How do I save only p-value from the result?
Thanks a lot!
2010 Jul 13
6
create variables with indexes
Hi, there:
Suppose I want create variables with indexes in their names, e.g., X_1_1, X_1_2, X_1_3, ..., X_1_10, X_2_1, X_2_2, X_2_3, .. X_2_10,..., X_10_1, X_10_2, ... X_10_10. It looks like I need to use 2 indexes I and J so I is looped from 1 to 10, and J is looped from 1 to 10. But I don't know how to automatically produce X with these combination of indexes. Should I use paste function?
2011 Jan 20
2
auc function
Hi, there.
Suppose I already have sensitivities and specificities. What is the quick R-function to calculate AUC for the ROC plot? There seem to be many R functions to calculate AUC.
Thanks.
Yulei
[[alternative HTML version deleted]]
2007 Oct 11
2
test for whether dataset comes from a known MVN
Dear all,
I have a multivariate dataset containing 100,000 or more points.
I want find the p-value for the dataset of points coming from a
particular multivariate normal distribution
With
mean vector u
Covariance matrix s2
So
H0: points ~ MVN( u, s2)
H1: points not ~ MVN( u, s2)
How do I find the p-value in R?
To me this is a likelihood ratio test problem.
In H0 the parameters are
2006 Feb 13
2
bivariate normal distribution
Hi, there.
Does anyone know the R function for calculating the cdf of bivariate
normal distribution function?
Thanks.
Yulei
[[alternative HTML version deleted]]
2008 Mar 06
2
calculate AUC and plot ROC in R
Hi, there:
Could someone tell me a simple function of plot ROC curve and calculate
AUC in R? My setting is very simple, a column of the true binary
response and another column of predicted probabilities.
Thanks!
Yulei
[[alternative HTML version deleted]]
2008 Jun 11
1
specifying ranges in scatter plot
Hi, there:
Does anyone know how to specify the ranges in the axises when I make
scatter plots using pairs()? In the general plot function, I can use
xlim and ylim option. But how can I do this if I use pairs()?
Thanks.
Yulei
[[alternative HTML version deleted]]
2006 Apr 08
1
cross product
Hi, there.
How do I calculate the cross-product in the form of
\sum_{i=1}^{n}X_{i}^{t} \Sigma X_{i} using R code without using do loop?
X_{i} is the covariate matrix for subject I, \Sigma is the covariance
matrix.
Thanks for your help.
Yulei
[[alternative HTML version deleted]]
2009 Apr 27
1
plot estimates and their 95% confidence intervals
Hi, there:
I have a dataset with 50 states and for each state, I have its associated mean estimate (for some parameters) and the lower and upper bound of the 95% CI. The data look like below:
state ami_mean ami_low ami_up
1 MS -0.58630 -0.90720 -0.29580
2 KY -0.48100 -0.75990 -0.19470
3 FL -0.47900 -0.62930 -0.32130
I would like to have a plot the 95% CI (characterized by
2006 Nov 07
1
multivariate splines
Hi,
I am looking for an R package that would calculate multivarite (mostly
2d and 3d, tensor) cubic interpolating splines, so that I could
evaluate these splines (and their derivatives) at many points (unkown
at the time of calculating the spline polynomials) repeatedly.
To make things concrete, I have an array V with
dim(V) = k
and gridpoint vectors grid=list(...), length(grid[[i]])==k[i],
2008 Feb 29
1
bugs.seed= and summary.only= option in R2WinBUGS
Dear R user:
I am using R2WinBUGs to call WinBUGS from R. But I have some problems in
using either the option bugs.seed and summary.only in the function bugs.
Here are the programs and error messages. It appears that if I don't use
either option, the program runs fine. I am using R2.5.1 and WinBUGs14.
The program is not running:
> schools.sim <- bugs(data, inits,
2006 Oct 11
1
Question about error of "non-numeric argument to binary operator"
Hi,
I have the following data and there is no binary operator contained,
however, I still receive the error message when running unitrootTest
function, could someone give me a guidance on it??
>readClipboard()
[1] "245" "246" "261.5" "275.5" "307" "284.5" "289" "313.5"
"323.75"