similar to: Comparing Proportions Among Groups

Displaying 20 results from an estimated 300 matches similar to: "Comparing Proportions Among Groups"

2012 Mar 01
2
Robust ARMA Fitting in R?
Hello, BODY { font-family:Arial, Helvetica, sans-serif;font-size:12px; } Does any one know if there are any functions/packages available in R for robust fitting of ARMA time series models (e.g., similar to the function arima.rob() in S-PLUS)? Many thanks and kind regards, Isabella Isabella R. Ghement, Ph.D. Ghement Statistical Consulting Company 301-7031 Blundell Road,
2008 Apr 16
3
Problems with R2WinBUGS
Hello, I am trying to use R2WinBUGS to conduct a mixed treatment comparison (MTC) analysis. On the surface, it seems to me that I am following the correct steps: (1) reading the data into R, (2) specifying initial values for the parameters in the model and (3) fitting the model to the data using the bugs() function in R2WinBUGS. However, I get the error message
2017 Sep 04
0
JSM 2018 Invited Session Proposals on Statistical Graphics and Data Visualization Due by September 7, 2017
Dear Colleagues, If you work in the statistical graphics and/or data visualization fields, please consider organizing an invited session for the JSM 2018 conference in Vancouver, whose theme is ?#LeadWithStatistics.? ASA's Section on Statistical Graphics will sponsor 3 invited sessions at JSM 2018, with a further 1-2 proposals having the potential to be included in the JSM 2018 conference
2008 Aug 18
2
use expression() in a loop
Hi all, I want to do plot() in a loop to make 10 graphs, so I have some code like for (i in 1:10) { plot(... ... , xlab = expression(g[i]) ) } I expect g_1, g_2, and so on appear on x labels, but it simply prints g_i for each graph. Does anybody know how to get around this problem? Thanks. NL
2009 Apr 14
1
mean fold change issues and p values
I am new to R and have two scripts written slightly different but should to relatively the same thing but my lack of experience with the program I can not figure out the what I need to do to correct it. The first script gives me a consistent mean fold change values with every run but can generate negative p values for some. For the second version of the script, the fold changes seem to be very
2003 Jul 21
4
generate a series of fucntion
Hi there, I want to generate a large amount of functions, say f=function(x,t) exp(-t[1]-t[2]*g_1(x)-t[3]*g_2(1+x)) where g_1(x) and g_2(x) are from a long list of moments, such as x, x^2, log(x), log(1+x) .. and so on. Any suggestions on how to do this efficiently? thanks a lot. x.w
2009 Nov 11
1
Unexpected behaviour for as.date()
Hi everyone, I am trying to use the function as.date() from the "dates" package in R 2.10.0 to convert a character date to a Julian date, as follows: > as.date("02-MAY-01", order="mdy") # convert May 2, 2001 to a Julian date [1] 2May1 However, when trying to convert a character date from the year 2000 to a Julian date, I get an <NA> instead of the desired
2010 Mar 25
1
how to deal with vector[0]?
Hi, I have a vector with 4 elements, e.g., tau_i=c(100,200,300,400), but potentially tau_i[0]=0. In a "for" loop, tau_i=c(100,200,300,400) m=4 tau_i[0]=0 # <------- ? P_i=1 for(i in 2:m) { P_i = P_i*(tau_i[i-1]-tau_i[i-2]) } Error in P_i = P_i * (tau_i[k - 1] - tau_i[k - 2]): replacement has length zero Unfortunately, I can add this potential element into
2011 Jan 21
2
ordering a vector
Hi, is there a R function that order a matrix according to some criteria based on the rows(or cols) of that matrix? For example, let's say that my matrix S is composed by n rows S_1, S_2,.., S_n and that I compute some real value g_i=g(S_i) for each row. Then I want to order this set of g_i (from smaller to bigger) and order the correspondent row to the new position. Is it possible (apart
2003 Oct 31
1
constrained nonlinear optimisation in R?
Hello. I have searched the archives but have not found anything. I need to solve a constrained optimisation problem for a nonlinear function (“maximum entropy formalism”). Specifically, Optimise: -1*SUM(p_ilog(p_i)) for a vector p_i of probabilities, conditional on a series of constraints of the form: SUM(T_i*p_i)=k_i for given values of T_i and k_i (these are constraints on
2012 Mar 20
1
How to write and analyze data with 3 dimensions
Suppose I have data organized in the following way: (P_i, M_j, S_k) where i, j and k and indexes for sets. I would like to analyze the data to get for example the following information: what is the average over k for (P_i, M_j) or what is the average over j and k for P_i. My question is what would be the way of doing this in R. Specifically how should I write the data in a csv file and how do I
1998 Feb 27
1
R-beta: is there a way to get rid of loop?
Here is a programming question. The code I am using is quite slow and I was wondering if there is a way to get rid of the for loop. I am dealing with "interaction" in 2x2 table, and am using Edwards's G_I (Likelihood, p. 194). I label the cells in the table as follows stim response "y" "n" total -------------------------------- y hit miss nsignal
2010 Oct 08
3
Efficiency Question - Nested lapply or nested for loop
My data looks like this: > data name G_hat_0_0 G_hat_1_0 G_hat_2_0 G_0 G_hat_0_1 G_hat_1_1 G_hat_2_1 G_1 1 rs0 0.488000 0.448625 0.063375 1 0.480875 0.454500 0.064625 1 2 rs1 0.002375 0.955375 0.042250 1 0.000000 0.062875 0.937125 2 3 rs2 0.050375 0.835875 0.113750 1 0.877250 0.115875 0.006875 0 4 rs3 0.000000 0.074750 0.925250 2 0.897750 0.102000
2006 Dec 28
0
lmer: Interpreting random effects contrasts and model formulation
I'm trying to fit a nested mixed model using lmer and have some questions about the output and my model formulations. I have replicate measures on Lines which are strictly nested within Populations. (a) So if I want to fit a model where Line is a random effect and Populations are fixed and the random Line effect is constant across Populations, I have: measure_ijk = mu + P_i + L_ij +
2009 Oct 28
2
regression on large file
Dear R community, I have a fairly large file with variables in rows. Every variable (thousands) needs to be regressed on a reference variable. The file is too big to load into R (or R gets too slow having done it) and I do now read in line by line with "scan" (see below) and write the results to out. Although improved, this is still very slow... Can someone please help me and suggest
2010 Dec 15
4
Generacion de binomiales correlacionadas
Buenas tardes, Estoy interesado en generar observaciones de una distribucion binomial bivariada en la que hay _cierto_ grado de correlacion (denotemoslo rho). Podria por favor alguien indicarme como hacerlo en R? Este es el contexto. Supongamos que se tienen dos experimentos en los que la variable respuesta _sigue_ una distribucion binomial, i.e., X_i ~Binomial(n_i, p_i), i=1,2 y que, por ahora,
2007 Jan 22
1
eval() parse() and problem with square brackets
Hello, i have problem with the following code (I'm using sqlQuery function from RODBC package): eval(parse(text="g_1 <- sqlQuery(cnn_1, \"select aa from bb.[cc\\dd].ee\")")). I get the error message: "[RODBC] ERROR: Could not SQLExecDirect" "S0002 208 [Microsoft][ODBC SQL Server Driver][SQL Server]Invalid object name 'bb.cc\dd.ee'." It
2007 Jan 22
1
eval() parse() and problem with square brackets
Hello, i have problem with the following code (I'm using sqlQuery function from RODBC package): eval(parse(text="g_1 <- sqlQuery(cnn_1, \"select aa from bb.[cc\\dd].ee\")")). I get the error message: "[RODBC] ERROR: Could not SQLExecDirect" "S0002 208 [Microsoft][ODBC SQL Server Driver][SQL Server]Invalid object name 'bb.cc\dd.ee'." It
2009 Nov 11
1
Unexpected behavior for as.date()
The date library was written 20 or so years ago. It was a very good first effort, but the newer Date library has superior functionality in nearly every way. The date library is still available, for legacy projects such as yours, but I do not advise it for new work. To answer your specific questions: 1. What you have is a real bug. The underlying C routine that scans through the text returns
2004 Dec 03
1
How to wrap or split labels on plot
Dear R gurus, I want to wrap labels that are too long for a plot. I have looked at strsplit(), substr(), nchar(), and strwrap(). I think it's some combination but I'm having difficulty trying to figure out the right combo. I think I need to create some new matrix containing the labels already split, though I'm not sure if maybe there is a quick and dirty way to address this