similar to: Simulating correlations with varying sample sizes

Displaying 20 results from an estimated 300 matches similar to: "Simulating correlations with varying sample sizes"

2007 Aug 07
2
Varying case sensitivity
Hi all, I''m using ferret 11.4 together with acts_as_ferret and I''ve indexed the geonames.org country files. These files contain worldwide locations in UTF-8 with all their different spellings each. Model definition is like this: class location acts_as_ferret :fields => {:location_names => {}}, :single_index => true ... end The instance method location_names
2003 Sep 10
0
Multivariate Kalman filter with time-varying coefficients
Hi Does anyone know of any R code for estimating a *multivariate* state space model using a Kalman filter where the output matrix H(t) is time-varying but predictable (i.e. measurable w.r.t information at time t-1) in the observation equation y(t) = H(t) z(t) + R w(t)? [Here y(t) are the observations, z(t) is the state variable, w(t) the observation error and R R' the observation error
2009 Mar 01
1
gamm (mgvc) and time-varying coefficient model
Dear R users, I have repeated measurements on individuals. I want to estimate the time-varying effect of a factor variable X (taking three levels), e.g. a model in the spirit of Hastie and Tibshirani (1993). I am considering using the package "mgvc" which implements generalized additive models, especially the function gamm, which estimates generalized additive mixed models, and thus,
2008 May 28
0
multistate survival analysis w/ time varying covariates
Hi, I've seen in the NestCohort package that one can do a hazard model with a binary outcome using covariates. I am interested in multistate hazard models with time-varying covariates, but can't seem to find this already implemented in an R package. Is this included somewhere but called something else? I feel like I've looked all over. Thanks! Michaela Gulemetova-Swan
2006 Sep 14
1
time varying covariates
Hello, I am trying to model an intensity function with time-varying covariates. Before, I have successfully defined a log likelihood function for a Power-Law Process (lambda(t)=alpha*beta*t^(beta-1)) with two paramters and no covariates for a repairable systems with failure times (t). This function was maximized with R optim. No problem! But now I want to include a covariate indicating a
2010 Sep 28
0
Time invariant coefficients in a time varying coefficients model using dlm package
Dear R-users, I am trying to estimate a state space model of the form (1) b_t = G * b_t-1 + w_t w_t ~ N(0,W) (2) y_t= A' * x_t + H' * b_t + v_t v_t ~ N(0,V) (Hamilton 1984: 372) In particular my estimation in state space form looks like (3) a3_t = 1 * a3_t-1 + w_t w_t ~ N(0,W) (4) g_t = (a1, a2) * (1, P_t)' + u_t * a3_t + v_t v_t ~ N(0,V) where g_t is the
2008 Mar 26
0
recursive multivariate filter with time-varying coefficients
Hi, I've been searching CRAN and the web for a recursive multivariate filter with time-varying coefficients. What I mean is the following: I have a series of square matrices A_t an initial value vector y_0 and I need to compute y_t =A_t%*%y_t-1 As these y_t may diverge quickly and/or lead to underflow problems, the y_t need to be scaled by eg y_t =y_t/sum(y_t-1) Is anyone aware
2001 Nov 14
0
CQB & links of varying capacity
Hi, I''ve been reading lots of documents and examples of setting up traffic shaping, and found that they _all_ refer to specific bandwidths for queues. I am using a dialup connection, and therefore can connect at different rates, and also have a dynamically changing ''bandwidth'' dependent on compression. What I want to do is to specify that interactive traffic (telnet,
2005 May 23
0
Left truncation in shared frailty models with time-varying covariates
Hi! I want to estimate a shared gamma frailty model with left truncated data. I use a parametric baseline hazard so that I can use simple ML estimation. As I have a big data set it is ok to assume piecewise constant baseline hazards. As my data are left truncated I have modified the definition of the risk set. Do I also have to modifiy the frailty distribution if I have left truncated data?
2006 Oct 23
0
Construction of Dataset for time varying COXPH analysis
Question: When survfit() function is used upon a coxph object, the 'n' returned is vastly smaller (n=6) than the number of distinct loans in the dataset used. I am trying to estimate a Cox proportional hazards model for a set of loans (over 6000) using using time varying covariates. For this 6000+ loans, I have some 62,000 different vectors representing the loans at different periods of
2014 Jan 29
0
[PATCH] nv30: report the correct max varying limit
nvfx_fragprog_assign_generic only allows for up to 10/8 texcoords for nv40/nv30. This fixes compilation of the varying-packing tests (although they still fail). Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu> Cc: 9.1 9.2 10.0 <mesa-stable at lists.freedesktop.org> --- src/gallium/drivers/nouveau/nv30/nv30_screen.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git
2018 Sep 28
0
multiple mounts each varying bitrates
I just realised my previous email didn't go to the list for some reason. Here it is again: Currently, I have three liquadsoap ".liq" files, and they all look very similar to this: -------- 8< -------- jake at beastie:/etc/liquidsoap$ cat jake.liq #!/usr/bin/liquidsoap #set("log.file.path","/tmp/basic-radio.log") def my_request_function() = # Get the
2003 Jan 31
2
Varying texts in expression(paste())
Hi, I am using R a lot to make plots relating to radioactivity, I am often using expression() to label the plots with nuclide names written with superscripts, e.g. expression(paste("Releases of ", { }^{99},Tc," (TBq/year)"))->ywtext But, is there any simple way to change the number and name of the nuclide through a variable? I tried nuccode=expression({ }^{99},Tc)
2004 Apr 07
1
Time Varying Coefficients
I'd like to estimate time varying coefficients in a linear regression using a Kalman filter. Even if the Kalman Filter seems to be available in some packages I can't figure out how to use it to estimate the coefficients. Is there anyway to do that in R? Any help appreciated Thanks
2006 Apr 03
2
testing proportional hazard in a Cox model including a time-varying covariate
I am using a syntax like coxph(Surv(start, stop, event) ~ X, data) to estimate the effect of X, which may change at each measurement (every 6 months). Is there anyone who knows a way to test the proportional hazard assumption in that case? Thank you in advance Jean-François Boudreau Sherbrooke University [[alternative HTML version deleted]]
2007 Jan 22
1
Time-varying correlation calculation
Dear R useres, I'm interested in getting a series of time-varying correlation, simply between two random variables. Could you please introduce a package to do this task? Thank you so much for any help. Amir --------------------------------- Don't pick lemons. [[alternative HTML version deleted]]
2007 Mar 16
1
cumsum over varying column lengths
Folks, I have a matrix of historicalReturns, where entry (i, j) is the daily return corresponding to date i and equity j. I also have a matrix startOffset, where entry (1, k) is the row offset in historicalReturns where I entered into equity k. So we have that NCOL(startOffset) = NCOL(historicalReturns). Now I would like compute for each column in historicalReturns, the cumulative return
2007 Jul 12
0
time-varying recursive filter - vectorized
A question about vectorized operations (avoiding loops, for speed)... I need to run a simple recursive (autoregressive) filter with a time-varying coefficient. It is just a one-step recursive filter, so it would be an exponential decay if the filter was constant. I just want to do this, where 'x' is the data and 'w' is the weight to apply to the previous time step: x <- c(1,
2009 Jun 28
2
Fold function with several time varying covariates
Hi I'm trying to use the fold function as described here: http://cran.r-project.org/doc/contrib/Fox-Companion/appendix-cox-regression.pdf Page9 It does say that you can use this when you have more than one time varying covariate: in the description of the argument cov it says: "cov: A vector giving the column numbers of the time-dependent covariate in data, or a list of vectors if there
2010 May 22
0
Modeling time varying effects in with cph: how to ?
Dear R users, I know, this is the second time i return on this topic. Sorry, but this analysis is of great value for me, and i hope someone can help me. I need to model a time-varying effect in a Cox model. Briefly explained here: http://books.google.com/books?id=9kY4XRuUMUsC&lpg=PP1&hl=it&pg=PA147#v=onepage&q&f=false