Displaying 20 results from an estimated 900 matches similar to: "Question on lists and vectors of lists"
2006 Jan 22
6
Making a markov transition matrix
Folks,
I am holding a dataset where firms are observed for a fixed (and
small) set of years. The data is in "long" format - one record for one
firm for one point in time. A state variable is observed (a factor).
I wish to make a markov transition matrix about the time-series
evolution of that state variable. The code below does this. But it's
hardcoded to the specific years that I
2004 Jul 05
2
Failing on reading a "slightly big" dataset
I have a file with 4 columns per line, all pipe delimited.
$ wc -l cmie_firm_data.text
89325 cmie_firm_data.text
$ ls -al cmie_firm_data.text
-rw-r--r-- 1 ajayshah ajayshah 4415637 Jul 5 15:25 cmie_firm_data.text
$ awk -F\| '(NF != 4)' cmie_firm_data.text
$ head cmie_firm_data.text
All figures are for the year 20030331|||
Company|GVA Less Interest (Rs. thousand)|Interest (Rs.
2004 Oct 03
2
Computing and testing transition probabilities?
Folks, I have a situation with many firms, observed for many years
(but it's not panel data, so every now and then data for a firm just
goes missing).
Let me show you an example. There are 3 firms "a", "b" and "c". There
are 3 years: 1981, 1982 and 1983. There's a factor f which takes
values 1, 2 or 3.
set.seed(5)
D = data.frame(
names=c("a",
2011 Jan 06
8
Accessing data via url
# Can anyone suggest why this works
datafilename <- "http://personality-project.org/r/datasets/maps.mixx.epi.bfi.data"
person.data <- read.table(datafilename,header=TRUE)
# but this does not?
dd <- "https://sites.google.com/site/jrkrideau/home/general-stores/trees.txt"
treedata <- read.table(dd, header=TRUE)
2006 Jan 19
2
Tobit estimation?
Folks,
Based on
http://www.biostat.wustl.edu/archives/html/s-news/1999-06/msg00125.html
I thought I should experiment with using survreg() to estimate tobit
models.
I start by simulating a data frame with 100 observations from a tobit model
> x1 <- runif(100)
> x2 <- runif(100)*3
> ystar <- 2 + 3*x1 - 4*x2 + rnorm(100)*2
> y <- ystar
> censored <- ystar <= 0
2011 Mar 23
2
) Error in eval(expr, envir, enclos) : object '' not found
> datafilename="E:/my documents/r/sex/bysex1.csv"
> data.sex=read.table(datafilename,header=T)
> data.sex
y.sex.age.region.c.n
1 1980,F,A,N,-18.15,13.61
2 1980,F,A,N,-18.61,13.04
3 1980,F,A,N,-18.81,12.32
4 1990,F,A,N,-21.12,11.7
5 1990,F,A,N,-20.77,11.58
6 1990,F,A,N,-21.6,13.34
7 1990,F,A,N,-21.78,12.6
> model.anova<-aov(c~age*sex,data=data.sex)
2010 Sep 20
2
interpreting one-way anova tables
Hi, I am trying to reconcile anova table in R (summary(lm)) with individual t.test.
datafilename="http://personality-project.org/R/datasets/R.appendix1.data"
data.ex1=read.table(datafilename,header=T) #read the data into a table
summary(lm(Alertness~Dosage,data=data.ex1))
gives:
Call:
lm(formula = Alertness ~ Dosage, data = data.ex1)
Residuals:
Min 1Q Median 3Q Max
2010 May 10
1
how to get p-value from ave
Hi there,
I checked google for aov. usually one uses summary to see whether the p-value is small.
but I want to put aov in my script. how can I get the p-value, (0.1115, 0.6665, 0.6665 in the following example)?
thanks
YU
> datafilename="http://personality-project.org/r/datasets/R.appendix2.data"
> data.example2=read.table(datafilename,header=T)
> aov.ex2 =
2012 Jun 10
1
compute Mcdonald's omega ω
Dear all
I am a newbie to R and I would appreciate it very much if someone can
give me some advice on this.
Please note that I am not a programmer so some of the questions might
sound really stupid.
I would like to compute McDonald's omega calculation using R, I'm
aware I can use the omega function in the psych package.
But I'm really not sure how to do it.
I have read these two
2008 Mar 17
4
How does one do simple string concatenation?
How does one convert objects c("a","b","c") and "d" into "abcd"?
> paste(c("a","b","c"), "d")
of course yields
[1] "a d" "b d" "c d"
--
Ajay Shah http://www.mayin.org/ajayshah
ajayshah at mayin.org
2004 Mar 01
6
Find out the day of week for a chron object?
I know that this is correct:
library(chron)
x = dates("01-03-04", format="d-m-y", out.format="day mon year")
print(x)
It gives me the string "01 Mar 2004" which is correct.
I also know that I can say:
print(day.of.week(3,1,2004))
in which case he says 1, for today is monday.
My question is: How do I combine these two!? :-) I have a
2008 Mar 18
3
Puzzled at generating combinations
I have two data frames. Suppose the first has rows
r1
r2
r3
and the second has rows
R1
R2
R3
I'd like to generate the data frame:
r1 R1
r1 R2
r1 R3
r2 R1
r2 R2
r2 R3
r3 R1
r3 R2
r3 R3
How would I go about doing this? I'm sure there's a clean way to do it
but I find myself thinking in loops.
--
Ajay Shah
2006 Mar 06
3
Interleaving elements of two vectors?
Suppose one has
x <- c(1, 2, 7, 9, 14)
y <- c(71, 72, 77)
How would one write an R function which alternates between elements of
one vector and the next? In other words, one wants
z <- c(x[1], y[1], x[2], y[2], x[3], y[3], x[4], y[4], x[5], y[5])
I couldn't think of a clever and general way to write this. I am aware
of gdata::interleave() but it deals
2008 Mar 07
4
Reading microsoft .xls format and openoffice OpenDocument files
1. I have used gdata::read.xls() with much happiness. But every now
and then it breaks. I have not, as yet, been able to construct a
mental model about the class of .xls files for which it works. Does
someone have a simple rule for predicting the circumstances under
which it will work?
2. Just like there is a read.xls(), it'd be great if we have a
read.ods() which directly
2006 Jan 26
2
Prediction when using orthogonal polynomials in regression
Folks,
I'm doing fine with using orthogonal polynomials in a regression context:
# We will deal with noisy data from the d.g.p. y = sin(x) + e
x <- seq(0, 3.141592654, length.out=20)
y <- sin(x) + 0.1*rnorm(10)
d <- lm(y ~ poly(x, 4))
plot(x, y, type="l"); lines(x, d$fitted.values, col="blue") # Fits great!
all.equal(as.numeric(d$coefficients[1] + m
2004 May 27
3
Date parsing question
How do I parse a date "yyyymmdd"? I tried asking chron(s, "ymd") but
that didn't work. Would the date parsing routines of the Date class of
1.9 grok this?
--
Ajay Shah Consultant
ajayshah at mayin.org Department of Economic Affairs
http://www.mayin.org/ajayshah Ministry of Finance, New Delhi
2008 Oct 15
2
"Heuristic optimisation"?
I wondered was people on this list felt about this article:
http://www.voxeu.org/index.php?q=node/2363
which talks about the problems of obtaining sound answers in numerical
optimisation in settings such as MLE or NLS.
--
Ajay Shah http://www.mayin.org/ajayshah
ajayshah at mayin.org http://ajayshahblog.blogspot.com
<*(:-? -
2004 Jun 21
2
Elementary sapply question
I am discovering sapply! :-) Could you please help me with a very
elementary question?
Here is what I know. The following two programs generate the same answer.
--------------------------------+----------------------------------------
Loops version | sapply version
--------------------------------+----------------------------------------
2007 Aug 31
2
Bugreport on integration of Sweave and latex beamer
I think I have isolated a problem with integration between Sweave and beamer.
Could you please see the file:
http://www.mayin.org/ajayshah/tmp/bugdemo.Rnw
Unfortunately, it uses some of my internal libraries, so you can't run
it. When I put it through Sweave, I get:
http://www.mayin.org/ajayshah/tmp/bugdemo.tex
which is, of course, a generic latex file which you can read and
2004 Feb 19
6
R for economists (was: Almost Ideal Demand System)
Hi,
I did not find any web page about using R in economics and econometrics so
far. However, this does not mean that there is none (searching with google
for "R" and "economics" gives many pages about economics and a name like
Firstname R. Lastname on it ;-)).
Does anybody in the list does know such a web page?
If not, I will be happy if you, Ajay, could build and