Displaying 20 results from an estimated 6000 matches similar to: "Extrapolated regression lines"
2007 Nov 15
3
Ancova doesn't return test statistics
Dear all,
I'm quite sure that this is a stupid question, but I'll ask anyway.
I want to perform an ANCOVA with two continuous factors and three
categorical factors.
Plant population growth rate (GR) = dependent variable
Seed reduction due to herbivory (SR) = continuous explanatory variable
Herbivore species (HS, 2 levels) = categorical explanatory variable
Population (Pop, 24 levels) =
2007 May 14
2
Make sign test show test statistics
When I perform a two-tailed sign test with the following simple syntax,
binom.test(59,100)
R returns a P-value (0.088) but nothing else. As I want the result for a
one-tailed test I take P/2 = 0.044). However, the journal to which I've
submitted my results requests the test statistics, not just the
P-values. How can I make R return the test statistics?
Best regards,
Johan Stenberg, Umea
2011 Jan 27
2
Extrapolating values from a glm fit
Dear R-help,
I have fitted a glm logistic function to dichotomous forced choices
responses varying according to time interval between two stimulus. x values
are time separation in miliseconds, and the y values are proportion
responses for one of the stimulus. Now I am trying to extrapolate x values
for the y value (proportion) at .25, .5, and .75. I have tried several
predict parameters, and they
2005 Mar 29
2
R-squared in Logistic Regression
Dear all,
How do I make R show the R-squared (deviance explained by the model) in
a logistic regression?
Below is how I write my syntax. Basically I want to investigate
density-dependence in parasitism of larvae. Note that in the end I
perform a F-test because the dispersion factor (residual deviance /
residual df) is significantly higher than 1. But how do I make R show
the
2012 Sep 25
1
Extrapolating Cox predicted risk
Dear all
I generated predicted risk of death for each subject in the study by
means of Cox proportional hazards model at 8 year of follow-up, a time
point at which follow-up was more than 90% complete. It is possible to
extrapolate to 10-year the predicted risk of each subjet by assuming
an exponential distribution?
Any help would be greatly appreciated.
Thanks for your consideration.
2006 Nov 20
1
sem package subscript out of bounds error
I'm having the most curious error while using the sem package. For
the model I'm working with, I keep getting the following error:
Error in J[cbind(1:n, observed)] <- 1 : subscript out of bounds
I''ve used debug=TRUE with sem, and there don't appear to be any
problems with model - there are no latent variables in this model.
The variables in the covariance matrix
2011 Jan 29
1
data extrapolation function
Readers,
Data was imported using the read csv command:
dataimport<-read.csv("/path/to/dataimport.csv")
10,2000
12,2001
13,2002
15,2003
17,2004
Using the help contents for 'predict.lm' (i.e. ?predict.lm) a new data
frame was created
dataimportextra<-data.frame(x=seq(1990,2010,1))
predict(lm(dataimport),dataimportextra[,2],se.fit=TRUE)
2011 Mar 29
2
List extraction
I have created a list of tables with the same columns but different number of
row.
Example (actual list has ~200 elements):
> temp1<- data.frame(ID=c("Herb","Shrub"),stat=c(4,5),pvalue=c(.03,.04))
> temp2<- data.frame(ID=c("Herb","Shrub",
> "Tree"),stat=c(12,15,13),pvalue=c(.2,0.4,.3))
> L<-list(a=temp1,b=temp2)
> L
$a
2010 Jan 27
2
using functions with multiple arguments in the "apply" family
typically, the apply family wants you to use vectors to run functions on.
However, I have a function, kruskal.test, that requires 2 arguments.
kruskal.test(Herb.df$Score,Herb.df$Year)
This easily computes the KW ANOVA statistic for any difference across
years....
However, my data has multiple sites on which KW needs to be run...
here's the data:
Herb.df<-
2007 Sep 29
1
templates with same name before extension are cached
Hi all,
I was just wondering if this is the intended behavior. Here is my setup:
controller
def index
respond_to do |f|
f.xml { render :xml => true }
f.html { render :layout => :none }
end
end
In my views I have a file for each type
index.herb
index.xerb
The first request I send is cached and interferes with the other one.
For example, if I send an xml request
2010 Feb 24
1
extracting results from wilcox_test (package::coin)
Recently, I ran a series of Kruskal-Wallace tests [kruskal.test()] using by()
to group by site Output is a list:
>Herb.KW
Herb.df$ID: 10-1
Kruskal-Wallis rank sum test
data: Indicator_Rating by Year
Kruskal-Wallis chi-squared = 15.24, df = 7, p-value = 0.03302
-----------------------------------------------------------------------------------------------------
Herb.df$ID: 18-1
2009 Jun 04
3
Plot and lm
I want to make a log-log plot with a regression line, but I can't figure
out what I'm doing wrong. What I'm trying is:
plot(mass,area, log="xy", pch=as.numeric(food))
abline(lm(mass~area))
or
plot(mass,area, log="xy", pch=as.numeric(food))
islands$logmass <- log(mass)
islands$logarea <- log(area)
attach(islands)
abline(lm(logmass~logarea))
But that does
2023 Oct 26
2
Plot for 10 years extrapolation
Dear R-Experts,
Here below my R code working but I don't know how to complete/finish my R code to get the final plot with the extrapolation for the10 more years.
Indeed, I try to extrapolate my data with a linear fit over the next 10 years. So I create a date sequence for the next 10 years and store as a dataframe to make the prediction possible.
Now, I am trying to get the plot with the
2009 May 27
1
Hierarchical glm with binomial family
Dear members of the R help list,
I want to do a hierarchical glm with binomial family but am unsure
about how to write the syntax which involves nesting.
I want to test whether the risk of being attacked by Herbivores for
Meadowsweet plants is significantly dependent on the Distance to
heterospecific source plants.
Dependent variable = Herbivory (yes/no)
Explanatory continuous variable =
2010 Nov 09
2
new column from column in another df
If I have a data frame where a species occupies several rows with different
phases such as (both col's ar factors):
species,phase
Populus tremula,1
Populus tremula,2
Populus tremula,3
Calluna vulgaris,1
Calluna vulgaris,2
Betula alba,1
Betula alba,2
Betula alba,3
Primula veris,1
Primula veris,2
and another df where each species only have one row:
species,growth_form
Populus tremula,tree
Acer
2011 Mar 08
1
NaNs in Nested Mixed Model
Dear R users,
I have a problem with something called "NaNs" in a nested mixed model.
The background is that I have studied the number of insect nymphs
emerging from replicated Willow genotypes in the field. I have 15
replicates each of 4 Willow genotypes belonging two 2 Willow species.
Now I want to elucidate the effect of Willow genotype on the number of
emerging nymphs. Previously I
2006 May 24
3
Regression line limited by the rage of values
Hi
In R, using plot(x,y) followed by abline(lm(y~x)) produces a graph
with a regression line spanning the whole plot . This means that the
line extends beyond the swarm of data points to the defined of default
plot region. With par(xpd=T) it will span the entire figure region. But
how can I limit a regression line to the data range, i.e between
(xmin,ymin) and (xmax,ymax)?
Sorry for
2011 Apr 20
1
Extrapolating data points for individuals who lack them
Hi,
We have an experiment where individuals responses were measured over 5 days. Some responses were not obtained because we only allowed individuals to respond within a limited time-frame. These individuals are given the maximum response time as they did not respond, yet we feel they may have done if given time (and by looking at the rest of their responses over time, the non-response days stand
2010 Feb 18
2
Extracting values from a list
I have run a kruskal.test() using the by() function, which returns a list of
results like the following (subset of results):
Herb.df$ID: 4-2
Kruskal-Wallis chi-squared = 18.93, df = 7, p-value = 0.00841
--------------------------------------------------------------------
Herb.df$ID: 44-1
Kruskal-Wallis chi-squared = 4.43, df = 6, p-value = 0.6187
So then, how do extract a vector
2005 Sep 22
1
How does the jitter buffer "catch up"?
> Hello,
Hi :)
First off, could you try to set your email client to break long lines before
transmitting? In my (somewhat outdated) pine, the lines appear as VERY long
lines when I try to reply, making it hard to read :)
Minor detail though, I should probably fix pine. Some day.
> The way you describe how the jitter buffer should be implemented makes me
> wonder: How does the