Displaying 20 results from an estimated 7000 matches similar to: "Convert continuous variable into discrete variable"
2013 Jan 22
2
Approximating discrete distribution by continuous distribution
Dear all,
I have a discrete distribution showing how age is distributed across a
population using a certain set of bands:
Age <- matrix(c(74045062, 71978405, 122718362, 40489415), ncol=1,
dimnames=list(c("<18", "18-34", "35-64", "65+"),c()))
Age_dist <- Age/sum(Age)
For example I know that 23.94% of all people are between 0-18 years, 23.28%
2011 May 13
6
Powerful PC to run R
Dear all,
I'm currently running R on my laptop -- a Lenovo Thinkpad X201 (Intel Core
i7 CPU, M620, 2.67 Ghz, 8 GB RAM). The problem is that some of my
calculations run for several days sometimes even weeks (mainly simulations
over a large parameter space). Depending on the external conditions, my
laptop sometimes shuts down due to overheating.
I'm now thinking about buying a more
2011 Sep 19
1
Binary optimization problem in R
Dear all,
I would like to solve a problem similar to a multiple knapsack problem and
am looking for a function in R that can help me.
Specifically, my situation is as follows: I have a list of n items which I
would like to allocate to m groups with fixed size. Each item has a certain
profit value and this profit depends on the type of group the item is in. My
problem is to allocate the items
2010 Mar 01
2
Advice wanted on using optim with both continuous and discrete par arguments...
Dear R users,
I have a problem for which my objective function depends on both discrete and continuous arguments.
The problem is that the number of combinations for the (multivariate) discrete arguments can become overwhelming (when it is univariate this is not an issue) hence search over the continuous arguments for each possible combination of the discrete arguments may not be feasible. Guided
2011 Apr 12
2
Testing equality of coefficients in coxph model
Dear all,
I'm running a coxph model of the form:
coxph(Surv(Start, End, Death.ID) ~ x1 + x2 + a1 + a2 + a3)
Within this model, I would like to compare the influence of x1 and x2 on the
hazard rate.
Specifically I am interested in testing whether the estimated coefficient
for x1 is equal (or not) to the estimated coefficient for x2.
I was thinking of using a Chow-test for this but the Chow
2004 Jul 12
2
Association between discrete and continuous variable
What's the reommended way, in R, to determine the strength of
association between a discrete variable and a continuous variable?
Yes, I have read the manuals, trawled the archives, &c.
2013 Apr 14
1
Problem plotting continuous and discrete series in ggplot with facet
I have data that plots over time with four different variables. I would
like to combine them in one plot using facet_grid, where each variable gets
its own sub-plot. The following code resembles my data
require(ggplot2)
require(reshape2)
subm <- melt(economics, id='date', c('psavert','uempmed','unemploy'))
mcsm <- melt(data.frame(date=economics$date,
2016 Apr 16
1
Social Network Simulation
Dear all,
I am trying to simulate a series of networks that have characteristics
similar to real life social networks. Specifically I am interested in
networks that have (a) a reasonable degree of clustering (as measured by
the transitivity function in igraph) and (b) a reasonable degree of degree
polarization (as measured by the average degree of the top 10% nodes with
highest degree divided by
2011 Mar 26
1
Effect size in multiple regression
Dear all,
is there a convenient way to determine the effect size for a regression
coefficient in a multiple regression model?
I have a model of the form lm(y ~ A*B*C*D) and would like to determine
Cohen's f2 (http://en.wikipedia.org/wiki/Effect_size) for each predictor
without having to do it manually.
Thanks,
Michael
Michael Haenlein
Associate Professor of Marketing
ESCP Europe
Paris,
2010 Nov 11
2
predict.coxph and predict.survreg
Dear all,
I'm struggling with predicting "expected time until death" for a coxph and
survreg model.
I have two datasets. Dataset 1 includes a certain number of people for which
I know a vector of covariates (age, gender, etc.) and their event times
(i.e., I know whether they have died and when if death occurred prior to the
end of the observation period). Dataset 2 includes another
2006 Dec 14
2
xyplot: discrete points + continuous curve per panel
I have a number of x, y observations (Time, Conc) for a number of Subjects
(with subject number Subj) and Doses. I can plot the individual points with
xyplot fine:
xyplot(Conc ~ Time | Subj,
Groups=Dose,
data=myData,
panel = function(x,y) {
panel.xyplot(x, y)
panel.superpose(???) # Needs more here
}
)
I also like to plot on
2010 Jul 14
1
Printing status updates in while-loop
Dear all,
I'm using a while loop in the context of an iterative optimization
procedure. Within my while loop I have a counter variable that helps me to
determine how long the loop has been running. Before the loop I initialize
it as counter <- 0 and the last condition within my loop is counter <-
counter + 1.
I'd like to print out the current status of "counter" while the
2011 Sep 21
2
Cannot allocate vector of size x
Dear all,
I am running a simulation in which I randomly generate a series of vectors
to test whether they fulfill a certain condition. In most cases, there is no
problem. But from time to time, the (randomly) generated vectors are too
large for my system and I get the error message: "Cannot allocate vector of
size x".
The problem is that in those cases my simulation stops and I have to
2010 Sep 08
1
Aggregating data from two data frames
Dear all,
I'm working with two data frames.
The first frame (agg_data) consists of two columns. agg_data[,1] is a unique
ID for each row and agg_data[,2] contains a continuous variable.
The second data frame (geo_data) consists of several columns. One of these
columns (geo_data$ZCTA) corresponds to the unique ID in the first data
frame. The problem is that only a subset of the unique ID
2012 May 08
1
Regression with very high number of categorical variables
Dear all,
I would like to run a simple regression model y~x1+x2+x3+...
The problem is that I have a lot of independent variables (xi) -- around
one hundred -- and that some of them are categorical with a lot of
categories (like, for example, ZIP code). One straightforward way would be
to (a) transform all categorical variables into 1/0 dummies and (b) enter
all the variables into an lm model.
2010 Jul 25
1
Equivalent to go-to statement
Dear all,
I'm working with a code that consists of two parts: In Part 1 I'm generating
a random graph using the igraph library (which represents the relationships
between different nodes) and a vector (which represents a certain
characteristic for each node):
library(igraph)
g <- watts.strogatz.game(1,100,5,0.05)
z <- rlnorm(100,0,1)
In Part 2 I'm iteratively changing the
2012 Apr 12
2
Curve fitting, probably splines
Dear all,
This is probably more related to statistics than to [R] but I hope someone
can give me an idea how to solve it nevertheless:
Assume I have a variable y that is a function of x: y=f(x). I know the
average value of y for different intervals of x. For example, I know that
in the interval[0;x1] the average y is y1, in the interval [x1;x2] the
average y is y2 and so forth.
I would like to
2012 Nov 13
2
Discrete trait Ornstein–Uhlenbeck in R?
Is there a package that will allow me to fit Brownian motion and
Ornstein?Uhlenbeck models of evolution for discrete traits? I know that
geiger and ouch have commands for fitting these models for continuous
traits, but these aren't suitable for discrete trait evolution, correct?
--
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2010 Mar 08
2
variance of discrete uniform distribution
Hi all,
I am REALLY confused with the variance right now.
for a discrete uniform distribution on [1,12]
the mean is (1+12)/2=6.5
which is ok.
y=1:12
mean(y)
then var(y)
gives me 13
1- on http://en.wikipedia.org/wiki/Uniform_distribution_%28discrete%29 wiki
the variance is (12^2-1)/12=143/12
2-
2012 Nov 16
1
discrete discriminant analysis
Hello,
I am using the mda package and in particular the fda routine to classify in
term of gear a set of 20 trips.
I preformed a flexible discriminant analysis (FDA) using a set of 151
trips.
FDAT1 <- fda(as.factor(gear) ~ . , data =matrizR)
A total of 22 predictors were considered. 20 of the predictors are
"numeric" and 2 are "factors/discrete".
The resulting FDA