Displaying 20 results from an estimated 1000 matches similar to: "Legend Truncated Using filled.contour"
2011 Jan 28
1
Problems making subsets with [] or "subset"
Hi,
I'm trying to make a model in order to know wich factors got?s influence in
the intensity of a infection, but just in the individuals who's got this
infection. In my data I've got a variable called "prevalence" with 2 levels:
1.- Infected individual
0.- Non infected
So what i'm trying to do is a subset in a model like this,
2007 Jun 28
2
sampling question
I am interested in locating a script to implement a sampling scheme
that would basically make it more likely that a particular observation
is chosen based on a weight associated with the observation. I am
trying to select a sample of ~30 census blocks from each ZIP code area
based on the proportion of women in a ZCTA living in a particular
block. I want to make it more likely that a block will
2011 Jan 12
2
Don´t know what test i have to use
Hello,
I?m starting with my PhD and I have to stop because i got a little knowledge
in R and statistics.
I?ve got a model of this kind:
binary response variable: prevalence of infection (0/1)
3 categorical independent variables: sex, month and name of the area
I was trying with a full model like this, before the simplification
model<-aov(prevalencia~sex*month*area)
but the Fligner test
2019 Oct 30
2
Dovecot and MySQL aborted connections.
We also spotted these sql connections getting aborted, upon upgrading
MySQL from 5.6 to 5.7. (Going back to 5.6 we don't see them!)
Turning on mysql general query logging we can see it is Dovecot's mysql
connections that inquire about or update quota usage in particular:
*** /logs//mysql.log ***
2019-10-30T10:52:22.624690-07:00 2 Connect dovecot at localhost on
npomail using
2024 Jan 17
1
Is there any design based two proportions z test?
Hello Everyone,
I was analysing big survey data using survey packages on RStudio. Survey
package allows survey data analysis with the design effect.The survey
package included functions for all other statistical analysis except
two-proportion z tests.
I was trying to calculate the difference in prevalence of Diabetes and
Prediabetes between the year 2011 and 2017 (with 95%CI). I was able to
2024 Jan 17
1
Is there any design based two proportions z test?
Dear Md Kamruzzaman,
To answer your second question first, you could just use the svychisq()
function. The difference-of-proportion test is equivalent to a chisquare
test for the 2-by-2 table.
You don't say how you computed the confidence intervals for the two
separate proportions, but if you have their standard errors (and if not,
you should be able to infer them from the confidence
2009 Jul 10
1
prevalence in logistic regression lrm()
Hi, I am wondering if there is a way to specify the prevalence of events in logistic regression using lrm() from Design package? Linear Discriminant Analysis using lda() from MASS library has an argument "prior=" that we can use to specify the prevalent of events when the actual dataset being analyzed does not have a representative prevalence. How can we incorporate this information in
2009 Jan 14
3
multiple secondary axes
Dear R experts,
I want to plot a line chart with another secondary axis placed right to
the standard secondary axis which one can access with the axis command, so
that the data lines are seen in the same plot. Is there any way to do this
in R?
Many thanks,
Kirsten.
2008 Jul 08
6
Question: Beginner stuck in a R cycle
Dear All,
I have a database of 200 observations named myD.
In the dataframe there are a column named code (with codes varying from 1 to 77), a column named "prevalence" with some quantitative measurements are given and an column named Pr_mean, with no values.
I would like to set a cycle to compute the average of prevalence values for each different code and store the averages under the
2004 Sep 06
4
Cox regression for prevalence estimates
Hello, I'm an MD working in an eye clinic. I'm learning by myself to use R
for use in my research works and for implementation in a software project.
There are some authors who recomends the use of Cox regression as a
substitute for Logistic regression (<a
href="http://www.biomedcentral.com/1471-2288/3/21.pdf"> Barros AJD, Hirakata
VN. BMCMedical Research Methodology, 2003;
2007 Jun 26
2
Aggregation of data frame with calculations of proportions
Dear all,
I have been stuck on this problem, am rather struggling and would
appreciate some advice if anyone can help. I apologise if this is a
bit long-winded, but I've tried to limit it to the bare essentials,
but don't know how to make it more generic!
I have some slightly odd real world data that I'm looking at
representing number of positive diagnoses for different diseases,
2009 Feb 26
1
error message and convergence issues in fitting glmer in package lme4
I'm resending this message because I did not include a subject line in my first posting.
Apologies for the inconvenience!
Tanja
> Hello,
>
> I'm trying to fit a generalized linear mixed model to estimate diabetes prevalence at US county level. To do this I'm using the glmer() function in package lme4. I can fit relatively simple models (i.e. few covariates) but when
2010 Sep 03
2
Interactions in GAM
Hello R users,
I am working with the GAM to inspect the effect of some factors (year, area) and continuous variables (length, depth, latitude and longitude) on the intensity and prevalence of the common parasite Anisakis. I would like introduce interaction in my models, both "continuous variables-continuous variables" and "continuous variables-factor". I have read some
2011 Dec 29
2
sorting a data.frame (df) by a vector (which is not contained in the df) - unexpected behaviour of match and factor
Dear R colleagues,
consider my data.frame named "df" with 3 columns - being level,
prevalence and sensitivity - and 7 rows of data (see dump below).
df <-
structure(list(level = structure(1:7, .Label = c("0", "1", "10",
"100", "1010", "11", "110"), class = "factor"), prevalence =
structure(c(4L,
2L, 3L,
2006 Jun 28
1
Simulate dichotomous correlation matrix
Newsgroup members,
Does anyone have a clever way to simulate a correlation matrix such that
each column contains dichotomous variables (0,1) and where each column
has different prevalence rates.
For instance, I would like to simulate the following correlation matrix:
> CORMAT[1:4,1:4]
PUREPT PTCUT2 PHQCUT2T ALCCUTT2
PUREPT 1.0000000 0.5141552 0.1913139 0.1917923
PTCUT2
2009 Jul 30
2
weight median by count for multiple records
Hello everyone,
I have a .csv file with the following format:
uniqueID SubjectID Distance_miles Tag
1 1001 5.5 3
2 1001 7 1
3 1001 6.5 1
4 1001 5 1
5 1002
2012 Jan 05
2
Bayesian estimate of prevalence with an imperfect test
Hi all!
I'm new to this forum so please excuse me if I don't conform perfectly to
the protocols on this board!
I'm trying to get an estimate of true prevalence based upon results from an
imperfect test. I have various estimates of se/sp which could inform my
priors (at least upper and lower limits even if with a uniform distribution)
and found the following code on this website..
2007 Jul 30
1
simple coding question
I have a list of ICD9 (disease) codes with various formats - 3 digit,
4 digit, 5 digit. The first three digits of these codes are what I am
most interested in. I would like to either add zeros to the 3 and 4
digit codes to make them 5 digit codes or add decimal points to put
them all in the format ###.##. I did not see a function that allows
me to do this in the formatting command. This seems
2008 Oct 31
1
replace() error: new columns would leave holes after existing columns
Hello, I have a problem with using replace() to convert a vector of dates
from yyyy-mm-dd to julian date.
For example, I type
replace(x,2004-05-14,134)
and I receive an error:
Error in `[<-.data.frame`(`*tmp*`, list, value = 134) :
new columns would leave holes after existing columns
If I can successfully convert, I have a script that will convert all of
the dates in
2009 May 20
3
error message re: max(i), but code and output seen O.K.
I have a researcher who is consistently get the warning message:
In max(i) : no non-missing arguments to max; returning -Inf
Best as I can tell the code is working properly and the output is as
expected. I would like some help in understanding why he is getting this
error message and what its implications are. I have his code.
Sincerely,
Kirsten Miles
Support Specialist
Research Computing Lab