similar to: lmer with random slopes for 2 or more first-level factors?

Displaying 20 results from an estimated 10000 matches similar to: "lmer with random slopes for 2 or more first-level factors?"

2009 Nov 06
2
Adjusting Yaxis (ylim) limits on a plotMeans(DV, IV1, IV2, error.bars="se")
Hello everyone, I have tried to look for this everywhere and so far have no luck. I have a plotMeans(DV, IV1, IV2, error.bars="se") graph that plots my data (DV-continuous, IVs are factors, IV1 - two levels, IV2-four levels). I am trying to increase a scale of my y-axis (to be consistent with my other graphs), but unfortunately nothing works with "plotMeans" function, which
2009 Feb 10
2
Mixed ANCOVA with between-Ss covariate?
Hi all, I have data from an experiment with 3 independent variables, 2 are within and 1 is between. In addition to the dependent variable, I have a covariate that is a single measure per subject. Below I provide an example generated data set and my approach to implementing the ANCOVA. However the output confuses me; why does the covariate only appear in the first strata? Presumably it should
2011 Feb 03
2
how to read the "Sum Sq" - column from summary.aov()
Dear R-Users, I have a trivial problem, but extensive googling and ??'ing did not solve it: I want to obtain the sums of squares from a summary.aov() object for later use. Example: > DV <- rnorm(100) > IV1 <- as.factor(rep(c("male", "female"), times = 50)) > IV2 <- as.factor(rep(c("young", "old"), times = 50)) > >
2011 Apr 18
1
regression and lmer
Dear all,  I hope this is the right place to ask this question. I am reviewing a research where the analyst(s) are using a linear regression model. The dependent variable (DV) is a continuous measure. The independent variables (IVs) are a mixture of linear and categorical variables. The author investigates whether performance (DV - continuous linear) is a function of age (continuous IV1 -
2008 Jun 22
1
two newbie questions
# I've tried to make this easy to paste into R, though it's probably so simple you won't need to. # I have some data (there are many more variables, but this is a reasonable approximation of it) # here's a fabricated data frame that is similar in form to mine: my.df <- data.frame(replicate(10, round(rnorm(100, mean=3.5, sd=1)))) var.list <- c("dv1",
2012 May 19
3
anovas ss typeI vs typeIII
Hi all, I have been struggling with ANOVAs on R. I am new to R, so I created a simple data frame, and I do some analyses on R just to learn R and then check them on SPSS to make sure that I am doing fine. Here is the problem that I've run into: when we use the aov function, it uses SS Type I as default (on SPSS it is Type III). Then I used the Anova function under cars package using the
2008 Nov 11
1
simulate data with binary outcome and correlated predictors
Hi, I would like to simulate data with a binary outcome and a set of predictors that are correlated. I want to be able to fix the number of event (Y=1) vs. non-event (Y=0). Thus, I fix this and then simulate the predictors. I have 2 questions: 1. When the predictors are continuous, I can use mvrnorm(). However, if I have continuous, ordinal and binary predictors, I'm not sure how to simulate
2013 Jun 23
1
2SLS / TSLS / SEM non-linear
Dear all, I try to conduct a SEM / two stage least squares regression with the following equations: First: X ~ IV1 + IV2 * Y Second: Y ~ a + b X therein, IV1 and IV2 are the two instruments I would like to use. the structure I would like to maintain as the model is derived from economic theory. My problem here is that I have trouble solving the equations to get the reduced form so I can run
2005 Jul 07
1
multivariate regression using R
Does anyone know if there is a way to run multivariate linear regression in R? I tried using the lm function (e.g., lm(dv1, dv2~iv1+iv2+iv3), but got error messages. Is my syntax wrong, or do I need a particular package? Thanks, Jeff-- ________________________________________________________ Jeffrey J. Lusk, Ph.D. Postdoctoral Research Associate Department of Forestry &
2008 Aug 22
1
filtering out data
Greetings, Apologies for such a simple question, but I have been trying to figure this out for a few days now (I'm quite new to R), have read manuals, list posts, etc., and not finding precisely what I need. I am accustomed to working in Stata, but I am currently working through the multilevel package right now. In Stata, I would include the statement "if model1 == 1" at the end
2011 Apr 16
0
regression questions (lm, lmer)
Dear all,  I hope this is the right place to ask this question. I am reviewing a research where the analyst(s) are using a linear regression model. The dependent variable (DV) is a continuous measure. The independent variables (IVs) are a mixture of linear and categorical variables. The author investigates whether performance (DV - continuous linear) is a function of age (continuous IV1 -
2002 Jan 04
1
plotting missing data patterns
I have one other problem and then I'll stop and get back to writing. I want to plot a missing data matrix (the R matrix a la Little and Rubin) to graphically depict where the missing data lie in the matrix. Some statistical packages produce a graphical depiction of the missing data patterns by plotting the matrix, color-coding the plot with contrasting colors for either missing or
2008 Sep 25
2
levelplot/heatmap question
Hello! I have data containing a large number of probabilities (about 60) of nonzero coefficients to predict 10 different independent variables (in 10 different BMA models). i've arranged these probabilities in a matrix like so: (IV1) (IV2) (IV3) ... p(b0) p(b0) p(b0) p(b1) p(b1) p(b1) p(b2) p(b2) p(b2) ... where p(b1) for independent variable 1 is p(b1 !=
2000 Jan 19
1
Potentially serious (but rare) issue with buffer.c and cipher.c
While rototilling packet.c, I did some looking at cipher_encrypt in cipher.c. It ends up that for SSH_CIPHER_NONE in cipher_encrypt, it uses memcpy. However, it also appears that dest and src can be equal in cipher_encrypt. On most sane libc implementations, memcpy == memmove. However, ANSI C makes no such guarantee, and some implementations out there are bound to try to optimize memcpy
2010 Aug 26
1
Random slopes in lmer
Hi I want to extract the random slopes from a lmer (I am doing a random regression), but are the answers obtained from ranef or coef? My model is: mod1<-lmer(B~ A +(A|bird), family=quasibinomial) And I want to obtain a slope for each individual bird but am not sure which output I need and can't find the answer anywhere. Thanks Sam Dr Samantha Patrick EU INTERREG Post Doc Davy 618
2006 Aug 24
1
lmer(): specifying i.i.d random slopes for multiple covariates
Dear readers, Is it possible to specify a model y=X %*% beta + Z %*% b ; b=(b_1,..,b_k) and b_i~N(0,v^2) for i=1,..,k that is, a model where the random slopes for different covariates are i.i.d., in lmer() and how? In lme() one needs a constant grouping factor (e.g.: all=rep(1,n)) and would then specify: lme(fixed= y~X, random= list(all=pdIdent(~Z-1)) ) , that?s how it's done in the
2013 Jan 10
0
Wald test for comparing coefficients across groups
Dear R users,    my question concerns my interest in comparing the beta coefficients between two identical regression models in two (actually 3) groups. Disclaimer: I am quite new to R, so I might be missing some terminology that I have not come across.   I am trying to find out if I can easily implement a Wald test in R for this, but the only relevant thing that I came across is this link
2001 Nov 13
2
des_ssh1_setiv not setting the IV ?
Greetings; I've been reading the OpenSSH source code and have a question about the des_ssh1_setiv function in cipher.c. (cut-n-pasted here from cipher.c v1.47) : static void des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) { memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv)); } This doesn't use the *iv parameter. Compare with: static void
2011 Sep 03
1
Lmer plot help
Hello all I'm running the lme4 package on my binomial data, and I'm happy with the model and the resultant plot. However, I'd like to plot my table data, which has: two IVs, and one DV. You can see an example below, where 'attractive' = question (IV), male = condition(IV/predictor) and no/yes = answer (dv). I'm using the table to investigate what questions act differently
2006 Dec 18
1
A question on lmer() function
Dear R users, We have encountered a slight problem when using the lmer() function: 1. Data description: 11 locations; Nt: monthly mosquito population density from 1994-2005 in each location. 2. Question: to examine the degree of spatial heterogeneity in the system by testing model support for single versus multiple intercepts and slopes for the location effect. We applied the lmer()