Displaying 20 results from an estimated 1000 matches similar to: "how to simulate brown, white and pink noise time series"
2009 Mar 21
3
Retrieving Vertices Coordinates from SpatialPolygons
Dear List,
I'm trying to use different R packages for my Teaching Assistantship
classes. And I cam out to an (apparently) very simple problem. I would
like to retrieve the vertices coordinate of a SpatialPolygon data. I
know this is stored in the "coords" slot, but I can't get access to
it! I tried to coerce the SpatialPolygon into a data.frame but it
doesn't work.
2007 Oct 17
1
problem with anova() and syntax in lmer
Dear R user
I have 2 problems with lmer.
The statistical consultance service of my university has recomended to me to
expose those problems here.
Sorry for this quite long message.
Your help will be greatly appreciated...
Gilles San Martin
1) anova()
I fit a first model :
model1 <- lmer(eclw~1 + density + landsc + temp + landsc:temp + (1|region) +
(1|region:pop) + (1|region:pop:family),
2000 Apr 04
0
stochastic process transition probabilities estimation
Hi all,
I'm new with R (and S), and relatively new to statistics (I'm a
computer scientist), so I ask sorry in advance if my question is silly.
My problem is this: I have a (sample of a) discrete time stochastic
process {X_t} and I want to estimate
Pr{ X_t | X_{t-l_1}, X_{t-l_2}, ..., X_{t-l_k} }
where l_1, l_2, ..., l_k are some fixed time lags. It will be enough for
me to compute
2000 Jun 07
1
forward stepwise selection
Dear R-Help,
My problem/bug came to light,when fitting a linear model using stepwise
selection. I'd started with the straightfoward command
step(lm(y~., dataset))
This worked fine, but because this starts with all the possible
explanatory variables, it results in a model with too many explanatory
variables. Hence I wanted to start with just a constant and do forward
selection, to get a
2010 Oct 28
3
0.3 is not 0.3, bug in seq() function?
Dear List,
I've been running a numerical simulation and I found this odd error in my code where the which command could not identify which rows of a column of data.frame were corresponding to the value 0.3. There are 7 unique values in this column (0.01,0.05,0.1,0.2,0.3,0.4,0.5), and this does not work only for 0.3. So I looked at the column and manually tried to use the which() command, and
2010 Dec 20
4
Time Series of Histograms
Dear List,
I have a set of distributions recorded at an equal interval of time and I would like to plot them as series of horizontal histograms (with the x-axis representing time, and y-axis representing the bins) since the distribution shifts from unimodal to multimodal in several occasions. What I would like to see is something close to a violinplot, but I do not want a kernel density
2014 Feb 19
1
[Bug 75202] New: Asus Maximus IV GENE-Z - Nvidia GTX660 - Strange pink line on left screen side
https://bugs.freedesktop.org/show_bug.cgi?id=75202
Priority: medium
Bug ID: 75202
Assignee: nouveau at lists.freedesktop.org
Summary: Asus Maximus IV GENE-Z - Nvidia GTX660 - Strange pink
line on left screen side
QA Contact: xorg-team at lists.x.org
Severity: normal
Classification: Unclassified
2014 Mar 05
1
[Bug 75800] New: [NVE4] [GTX660Ti] Pink line on left side of monitor and slightly blurry areas on screen
https://bugs.freedesktop.org/show_bug.cgi?id=75800
Priority: medium
Bug ID: 75800
Assignee: nouveau at lists.freedesktop.org
Summary: [NVE4] [GTX660Ti] Pink line on left side of monitor
and slightly blurry areas on screen
Severity: minor
Classification: Unclassified
OS: Linux (All)
Reporter:
2017 Aug 23
9
[Bug 102368] New: Since Archlinux testing migrate to mesa 17.1.7, I got a pink overlay in webcam software.
https://bugs.freedesktop.org/show_bug.cgi?id=102368
Bug ID: 102368
Summary: Since Archlinux testing migrate to mesa 17.1.7, I got
a pink overlay in webcam software.
Product: Mesa
Version: unspecified
Hardware: Other
OS: All
Status: NEW
Severity: normal
Priority: medium
2013 May 01
1
selecting rows based on multiple criteria
Dear List,
I am struggling with the following problem.
Suppose I have the following data.frame:
coord<-expand.grid(x=1:10,y=1:10)
and I want to extract the row numbers of those matching the criteria defined by the following data.frame:
choice<-data.frame(x=c(2,1,2),y=c(1,2,2))
the result should return in this case:
2,11,12
All I managed to do is the following:
which(data
2014 Feb 19
18
[Bug 75203] New: Asus Maximus IV GENE-Z - Nvidia GTX660 - Strange pink line on left screen side
https://bugs.freedesktop.org/show_bug.cgi?id=75203
Priority: medium
Bug ID: 75203
Assignee: nouveau at lists.freedesktop.org
Summary: Asus Maximus IV GENE-Z - Nvidia GTX660 - Strange pink
line on left screen side
QA Contact: xorg-team at lists.x.org
Severity: normal
Classification: Unclassified
2010 Dec 19
3
monthly median in a daily dataset
Hello,
I have a multi-year dataset (see below) with date, a data value and a flag
for the data value. I want to find the monthly median for each month in this
dataset and then plot it. If anyone has suggestions they would be greatly
apperciated. It should be noted that there are some dates with no values and
they should be removed.
Thanks
Emily
> print ( str(data$flow$daily) )
2006 Mar 03
1
Fractional brownian surfaces
Hi list,
I'm trying to generate fractional brownian surfaces in R.
[A detailed description with respect to various techniques to generating
these neutral landscapes has been described by Timothy Keitt (spectral
representation of neutral landscapes, Landscape Ecology, 2000) and
probably various other authours.]
Are there any packages that deal with this or related items? I've been
2006 May 12
11
Stupid? question about if else logic
this seems so stupid, I keep thinking I''ve dealt with this before but I
have this code
<h1>Portraits</h1>
<% if @image.portrait == 1 %>
<%= image_tag(url_for_file_column ''image'', ''file'', ''thumb'') %>
<% else %>
<h1>Landscapes</h1>
<%= image_tag(url_for_file_column
2008 Jul 04
2
Interface between fractal geometry and statistics
Are there any packages that help with statistical analysis in situations where
fractal geometry is relevant? Perhaps something that supports computation of
fractal related statistics, such as the Hurst exponent or fractal dimension?
Or perhaps which support obvious tasks such as taking samples from a dataset
at different levels of granularity (such as sampling spatial data at cm, m, km
2001 Dec 12
1
can't vectorize an expression
Dear R support network
I have a problem that is driving me crazy.
I have a dataframe with about 74000 landscapes which I call "land". A
landscape is a 2km -by- 2km square.
Land has three columns: land$lat, land$long, and land$description.
The last one holds a NON-unique (integer) description of each
landscape. There are maybe 100 distinct descriptions. Identifying
landscapes that
2004 Jun 21
2
Welch-JM-Test or Brown-Forsythe-Test in R?
Does oneway.test do what you want?
Hope this helps,
Matt Wiener
-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Sven Hartenstein
Sent: Monday, June 21, 2004 3:23 PM
To: r-help at stat.math.ethz.ch
Subject: [R] Welch-JM-Test or Brown-Forsythe-Test in R?
Hi,
I want to test mean differences of > 2 groups with
2006 Jan 09
1
brown, durbin , evans ( 1975 )
Does anyone know where
I can get R code for plotting
the Brown , Durbin
and Evans cumsum
procedure ( 1975 ) ?
I wrote my own code but
I am a little worried
that my confiodence bands
may not be correct ( I find the formula
in the original paper confusing and S+Finmetrics
has a formula but that formula implies that
there should be 4 lines as far as I can tell ) so
I would like to see someone
2005 Jun 28
1
Brown-Forsythe Test
Hi,
do anyone know which statistical software have the Brown-Forsythe Test for
differences of numerical continue data groups wich variance heterogenity?
not ofr evaluate the homogenity of variances, for evaluated the differences
between groups as ANOVA.
thanks
Jos?? Herrera
M??xico
_________________________________________________________________
T1msn Search. Todo lo que buscas ahora m??s
2008 Apr 16
1
Brown-Forsythe F* Statistic
I've been searching around for a function for computing the
Brown-Forsythe F* statistic which is a substitute for the normal ANOVA
F statistic for when there are unequal variances, and when there is
evidence of non-normality. A couple of other people have asked this
question, the responses I found have been:
?oneway.test
However, that function appears to use the Welch W statistic which,