Displaying 20 results from an estimated 1000 matches similar to: "model selection with step function"
2004 May 19
3
greek letters in plots
Hi,
I want to write in x axis label "fitted value of lambda" (lambda in greek
letter).
xlab=expression(lambda) gives the "lambda", I tryed things like xlab=paste
("fitted value of ", expression(lambda)) but I didn't get the greek letter.
Thanks in advance for any hint.
Antonio Olinto
-------------------------------------------------
WebMail Bignet - O seu
2006 Aug 07
2
finding x values to meet a y
Hi,
I'd like to find which values of x will give me a y.
In other words, in the example of a gaussian curve, I want to find the values of
x that will give me a density, let's say, of 0.02.
curve(((1/(sqrt(2*pi)*10))*exp(-((x-50)^2)/(2*10^2))),xlim=c(0,100))
Thanks for any help,
Antonio Olinto
-------------------------------------------------
WebMail Bignet - O seu provedor do
2004 Jun 18
1
cross table
Hi,
I have a dataframe with 3 columns: month (1 to 12), length and length class.
I'm trying to make a cross table with the counts of lengths per length class
and month. I don??t have all classes per month.
| 1 2 3 ...
-------------
120 | 0 1 0
150 | 5 6 0
170 | 3 0 7
...
I have already tryed many commands, without success - unfortunately.
May someone help me? Thanks in advance!
2004 Dec 06
1
using subset
Hi,
I have doubts in using subset command. I have a list of, lets say, 15 species
and I want to make a subset with only 2 of them. I??m the command
data2 <- subset(data1, species=="sp1"|species=="sp2")
Nevertheless, when I ask for the summary (summary(data2)) the others species
names still apearing. Also I tried
data2<-data1(data1$species %in%
2004 Apr 25
2
nonparametric multiple sample comparison
Hello all,
Here goes one of my first functions.
I want to make a nonparametric multiple sample comparison with unequal sample
sizes (see Zar?s Biostatistical Analysis, 3rd. Ed., pg. 201 Example 10.11, pg.
288 Example 11.10). In the real world, I want to compare samples of fish
length captured with different fishing gears.
After using the Kruskal-Wallis test I want to check the differences
2005 Dec 27
0
installing google earth
Hello,
This is my first post to this list.
Well, I tried to install Google Earth using WineTools but I got the "Unknown
Graphics Card" error. I can open the program but Earth doesn't appear.
I'm running Debian Sarge on a ASUS CUW(E)-FX motherboard (Intel 810 Chipset) and
Gnome 2.10.2 inteface.
Thanks for any help.
Best regards,
Antonio
--
Ant?nio Olinto
Biologist /
2006 Jun 16
0
prob in sample function
Hi,
I have a data set with values (L) varying from 1 to 700, with repeated numbers,
and I want to sample them according to the probabilities given by a logistic
curve P=1/(1+e(-r*(L-Lc))) where r gives "S" the inclination
and Lc the "rotation point". P ranges from 0 to 1.
As I could see I cannot use this P as prob in sample function. I'd need the
probabilities as given by
2005 Apr 13
1
barplot usage
Hi,
I?m trying to make a barplot with the following dataframe, with information on
relative frequency per sediment type (ST) for some species:
Species ST1 ST2 ST3
SP_A 10 60 30
...
At x-axis are (should be ...) the species names and at y-axis the frequency per
sediment, in stacked bars.
I tried to use barplot command but with no results. Could anyone help me on this?
Thanks in
2001 Sep 23
1
plot and lm (2)
Thanks for your reply Nassar.
What I really want is to overlay (like add=TRUE) the plots 1 and 2. With
plots "at the same screen" I meant overlaid and not one beside the other,
i.e., only one plot with all the points (1 to 10) in blue (or any other
color), the points 5 to 9 in red and a regression line from points 5 to 9.
Best regards,
Antonio Olinto
----- Original Message -----
2001 Sep 11
2
data frames
Dear R-list members
Here goes a question on data frames:
I want to create a new data frame excluding some records
(rows) from an existing one.
Considering the data frame "fish.dat" at the end of this
message, I can make a boxplot(Ring~Radius) and identify the
points at rows 11 and 25 as outliers.
With the command fish.dat[c(11, 25),] I can identify which
fishes are related to
2008 Apr 10
4
File locks?
Hello,
Recently, the following problem started happening with a particular samba
server:
If i have a file open for reading (say, a pdf in xpdf) and then try to write
to it (say, through recompiling a latex document) it complains that it
cannot open the file for writing.
this seems like a file lock issue but I am unsure where it is happening. My
previous usage should be perfectly safe since
2003 May 06
2
Compile R into a standalone EXE for WINNT
Hi,
I have an R script (transferred from SPLUS) and would like to compile a
standalone EXE (or DLL)
for WINNT. Would somebody know how this works or how it could be done ?
Thanks so much for any hints and suggestions; best regards
F.
Falk Huettmann
Geography Dept.-Earth Science-
2500 University Drive N.W.
University of Calgary
Calgary AB, T2N 1N4 CANADA
Email: falk at ucalgary.ca
Tel. 403
2001 Sep 25
2
max-min plot
Hello R-list members,
I’m trying to make a min-avg-max plot (like a boxplot, without
box and outliers, i.e., for each class of "x" a vertical line
indicating the range (max-min) and an horizontal line or point
indicating the mean) with data like:
Year Avg Min Max
98 10 7 13
99 12 10 15
01 11 6 14
Which command should be used?
Many thanks,
Antonio Olinto
2006 May 31
2
a problem 'cor' function
Hi list,
One of my co-workers found this problem with 'cor' in his code and I confirm it too (see below). He's using R 2.2.1 under Win 2K and I'm using R 2.3.0 under Win XP.
===========================================
> R.Version()
$platform
[1] "i386-pc-mingw32"
$arch
[1] "i386"
$os
[1] "mingw32"
$system
[1] "i386, mingw32"
$status
2008 Jun 20
1
Unexpected Behavior (potentially) in t.test
Greetings,
I have stumbled across some unexpected behavior (potential a bug) in, what I
suspect to be R's (2.6.2 on Ubuntu Linux) t.test function; then again the
problem may exist in my code. I have shutdown R and started it back up,
re-run the code and re-experienced the error. I have searched on Google for
the abnormal termination error message "(stderr < 10 * .Machine$double.eps *
2001 Sep 07
3
fitting models with gnls
Dear R-list members,
Some months ago I wrote a message on the usage of gnls (nlme library) and here I come again.
Let me give an example:
I have a 10 year length-at-age data set of 10 fishes (see growth.dat at the end of this message) and I want to fit a von Bertalanffy growth model, Li= Linf*(1-exp(-k*(ti-t0))) where Li = length at age i, Linf= asymptotic length, k= curvature parameter, ti=
2009 Jun 15
4
books on Time series
Dear list fellows,
I want to study time series and use R to analyse time series of fishing
data from several species (landings and cpue) investigating the
correlation between them and with environmental factors (water
temperature, wind, etc.).
Searching at Amazon I found three books with examples in R:
Time Series Analysis: With Applications in R by Jonathan D. Cryer and
Jonathan D. Cryer
2013 Jan 21
2
Regex for ^ (the caret symbol)?
Hello R-helpers,
I am trying to search for string that includes the caret symbol, using the
following code:
grepl("latitude^2",temp)
And R doesn't like that. It gives me:
> temp<-c("latitude^2","latitude and latitude^2","longitude^2","longitude
and longitude^2")
> temp
[1] "latitude^2" "latitude and
2001 Dec 17
2
Traffic shapping + routing in RH 7.1
0 *H
010 +0 *H
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charset="iso-8859-1"
Content-Transfer-Encoding: 8bit
Hi ALL,
I''m new to TC and IPTABLES and i need help in setting up a filter/routing
solution to an ISP.
I''ve read all the HOWTOs and i''ve reading LARTC messages for a month now.
I still don''t have a clue on how to do it ''cause sometimes people say
2006 Mar 28
2
Welch test for equality of variance
Hello
Using R 2.2.1 on a Windows machine.
Has anyone programmed the Welch test for equality of variances?
I tried RSiteSearch, but this gave references to t test and
oneway.test, which are not quite what I need.....I need the Welch test
itself, for use in a meta-analysis (to determine if variances are
equal).
TIA
Peter
Peter L. Flom, PhD
Assistant Director, Statistics and Data Analysis