Displaying 20 results from an estimated 2000 matches similar to: "New Learner"
2011 Nov 04
4
How to delete only those rows in a dataframe in which all records are missing
Hi,
Imagine I have the following data frame:
> a <- c(1,NA,3)
> b <- c(2,NA,NA)
> c <- data.frame(cbind(a,b))
> c
a b
1 1 2
2 NA NA
3 3 NA
I want to delete the second row. If I use na.omit, that would also affect the third row. I tried to use a loop and an ifelse clause with is.na to get R identify that row in which all records are missing, as opposed to the first
2013 Feb 21
2
Arimax with intervention dummy and multiple covariates
Hi
I'm trying to measure the effect of a policy intervention (Box and Tiao, 1975).
This query has to do with the coding of the model rather than with the particulars of my dataset, so I'm not providing the actual dataset (or a simulated one) in this case, apart from some general description.
The time series are of length n=34 (annual observations between 1977 and 2010). The policy
2013 Jul 22
1
about mix type clust algorithm
Hi:
I have tried to find the appropriate clust algorithm for mixed type of data.
The suggested way I see is:
1. use daisy to get the dissimilarity matrix
2. use PAM/hclust by providing the dissimilarity matrix, to get the clusters
but by following this, when the data set grows bigger say 10,000 rows of data, the dissimilarity matrix will be O(n^2), and out of memory will occur.
I am
2013 Jul 05
1
kruskal.test followed by kruskalmc
Hi all,
After running kruskal.test I have got results (p<0,005) pointing to reject
the hypothesis that the samples were draw from the same population.
Howerver when I run the kruskalmc there are no significant differences in
any of the multiple comparisons. Is that possible? Some clarification?
Thanks, Humber
<https://sites.google.com/site/humberandrade>
[[alternative HTML version
2013 Mar 22
4
error while extracting the p-value from adf.test
Hello all,
I tried to extract the p-value from adf.test in tseries; however, I got the error message such as
> ht=adf.test(list.var$aa)
> ht$p-value
Error in ht$p - value : non-numeric argument to binary operator
> ht
Augmented Dickey-Fuller Test
data: list.var$aa
Dickey-Fuller = -2.3147, Lag order = 4, p-value = 0.4461
alternative hypothesis: stationary
> ht$data
[1]
2012 Nov 09
1
predict.zeroinfl not found
Hi Just a quick problem that I hope is simple to resolve. I'm doing some work with zero inflated poisson models using the pscl package. I can build models using zeroinfl and get outputs fom them with no problem, but when I try to use the predict.zeroinfl function, I get Error: could not find function "predict.zeroinfl".
I was using an older version of R, but still had the same
2012 Oct 16
1
anova test for variables with different lengths
Hi all,
I want to test whether the MEAN of two different variables, (and
different number of observations) are the same. I am trying to use the
anova test but it doesn't seem to like that the number of observations
are different:
a=c(1:5)
b=c(1:3)
aov_test=aov(a~b)
>>Error in model.frame.default(formula = a ~ b, drop.unused.levels = TRUE) :
variable lengths differ (found for
2012 Nov 08
1
Dabbling with R5 setRefClass - Inheritance problems
Hello,
I wrote a class like so:
> rcfdpsuperclass <- setRefClass(
> Class="rcfdpsuperclass",
> fields = list(
> RcfpdVersion = "character"),
> methods = list(
> initialize = function(){
> 'Populates fields with defaults and lock as appropriate'
> initFields(
> RcfpdVersion =
2012 Sep 27
2
Is there a function that runs AR model with Schwarz Bayesian Information Criteria (BIC)?
Hello,
Is there a function in R by which one can run AR model with Bayesian
Information Criteria (BIC)? To my knowledge, functions ar and ar.ols could
select the order only by AIC.
Thanks,
Miao
[[alternative HTML version deleted]]
2013 Apr 09
4
Boxplot Labels OK
Dear all,
I have just sent an enquiry but probably I hadn’t expressed myself properly.
Could anyone help me with the following?
When I run the code on my data I get a boxplot with outliers identified by numbers 200 & 201.
However, what I would like is to label these outliers with their corresponding “DATA$num” values of the data frame.
In this example, the outliers should be labelled as:
2012 Aug 22
2
Fwd: Need help
Dear colleagues.
I wonder if anybody knows about a procedure in R to calculate the
Berger-Parker index and the Brillouin Diversity index.
I searched the net but did not find anything good about it.
Thanks a lot for any help
Mayo, Elvira.
[[alternative HTML version deleted]]
2012 Nov 07
1
Welch Two Sample T-Test
I know when I enter this into R:
> x = c(15, 10, 13, 7, 9, 8, 21, 9, 14, 8)
> y = c(15, 14, 12, 8, 14, 7, 16, 10, 15, 12)
> t.test(x,y,alt="less",var.equal=TRUE)
it shows:
Two Sample t-test
data: x and y
t = -0.5331, df = 18, p-value = 0.3002
alternative hypothesis: true difference in means is less than 0
95 percent confidence interval:
-Inf 2.027436
sample
2013 Apr 17
1
Anova unbalanced
Hello everybody,
I have got a data set with about 400 companies. Each company has a
score for its enviroment comportment between 0 and 100. These companies
belong to about 15 different countries. I have e.g. 70 companies from
UK and 5 from Luxembourg,- so the data set is pretty unbalanced and I
want to do an ANOVA. Somthing like aov(enviromentscore~country). But the
aov function is just for
2013 Apr 11
1
Calculating std errors of marginal effects in interactions
Hi! I've been looking for a way to calculate std errors of marginal effects
when I use interaction terms, but with no success. I pretty much have two
cases: continuous variable * continuous variable, and continuous variable *
binary variable. In both cases, I know how to calculate the marginal
effects, even with simulation.
But I still can't figure out how to calculate the std errors of
2012 Sep 09
5
qplot with many files (each one curve)
Hi,
i would like to plot a few hundred .csv files.
Each file contains one curve with x,y values to plot.
I have been searching for "gnu r read many files qplot"
and similar words. I found for loops that use assign to generate
one variable containing a dataframe.
When i uesed the classic "plot' command i could add
the curves with something like
for... {
2012 Oct 18
1
Time Series Analysis and Forecasting
Hello,
I am totally new in the field of time series analysis and forecasting and R.
I read that R is a powerful tool for time series. Could anyone give me
navigation what models of time series are availiable in R etc?
--
View this message in context: http://r.789695.n4.nabble.com/Time-Series-Analysis-and-Forecasting-tp4646637.html
Sent from the R help mailing list archive at Nabble.com.
2013 Jul 12
3
Needing help for excluding vector elements
Hello,
R for Dummies.
How can I exclude the first 1000 values of a vector (length 12000)? More
generally all the values up to the ith?
Thanks for your help,
Dr Olivier Charansonney
Cardiologue
Centre Hospitalier Sud-Francilien, Corbeil-Essonnes, France
[[alternative HTML version deleted]]
2012 Nov 09
2
Simple Likert count data visualization
Hello,
Before I start to construct something inferior myself I would like to know if such a plot function is already out there.
I have count data of a small survey with a few questions which use a scale from "Strongly disagree" to "Strongly agree" and similar things. What I would like to have for a slide is a plot which shows for each question a line over this scale and the
2012 Nov 08
1
A panel of contour plots through a iteration process
Dear all,
as you can see from the code I want to create *a panel of 11 contour
plots through
a iteration process*. I found a thread that address the issue of plotting
many contour.plots in the same device, but it does not address my problem!
I emphasize that the 11 contour plots must be appeared in the same device
through an iteration process and NOT individually!
par(mfrow=c(4,3)) # I want them
2012 Nov 26
3
How to count the number of different elements in a column
Hello,
Suppose that i have a dataframe
a <- read.dta("banca_impresa.dta")
i have a column with 17900 obs like
1
2
3
1
6
7
8
3
4
4
and i want to know the number of the different values so in this case it
would be 7
How can i do?
Thank you
--
View this message in context: http://r.789695.n4.nabble.com/How-to-count-the-number-of-different-elements-in-a-column-tp4650825.html
Sent