similar to: Visual stimulus presentation using R?

Displaying 20 results from an estimated 1100 matches similar to: "Visual stimulus presentation using R?"

2011 Jan 05
2
Problem with 2-ways ANOVA interactions
Dear All, I have a problem in understanding how the interactions of 2 ways ANOVA work, because I get conflicting results from a t-test and an anova. For most of you my problem is very simple I am sure. I need an help with an example, looking at one table I am analyzing. The table is in attachment and can be imported in R by means of this command: scrd<-
2011 Jan 09
2
Post hoc analysis for ANOVA with repeated measures
Dear all, how can I perform a post hoc analysis for ANOVA with repeated measures (in presence of a balanced design)? I am not able to find a good example over internet in R...is there among you someone so kind to give me an hint with a R example please? For example, the aov result of my analysis says that there is a statistical difference between stimuli (there are 7 different stimuli). ...I
2003 Jun 11
1
COX PH models for event histories?
This is a question about the use of the Cox proportional hazards model to analyze event histories. I am looking at the responses of sympathetic nervous system activity to a stimulus. The activity I observe is a burst that can only occur once per heart beat cycle (e.g., a binary count). Typically bursts occur in 60-80% of the heart cycles * sensory stimuli can modify these burst probabilities.
2005 Dec 01
1
LME & data with complicated random & correlational structures
Dear List, This is my first post, and I'm a relatively new R user trying to work out a mixed effects model using lme() with random effects, and a correlation structure, and have looked over the archives, & R help on lme, corClasses, & etc extensively for clues. My programming experience is minimal (1 semester of C). My mentor, who has much more programming experience, but a comparable
2011 Oct 07
1
ANOVA/ANCOVA Repeated Measure Mixed Model
Hello, I am trying to test some results I have for significance. It has been recommended that I use R and I am completely new to this. Set-up: Groups: two groups of 8 subjects (16 total) Two conditions: alert and passive Measurements: responses for three different stimuli (A, B, and C) measured in each condition Experiment: Testing the order of conditions Group one: Alert A, B
2010 Jun 09
1
ANOVA of a sort
Dear R Help, I have a general question - I know this is the R list, but I hope someone can help me out a little as I've always found the help here to be absolutely fantastic. I have run a psychological study where participants are given multiple stimuli and their responses to those stimuli are measured on the same numerical scale, i.e., the data is something like Participant Stimulus
2010 May 31
2
Ignoring initial rows in a text file import
I am trying to import a series of text files generated by stimulus presentation software. The problem that I am having is that the number of rows I need to skip is not fixed (depending on subject's pretest behavior) nor is the first row of the data I want always the same (the stimuli were presented in random order). So I need to bring in the .txt file (using readLines?), look for the row
2008 Dec 12
1
Support vector model?
Dear All, Apologies for sending this email to both list, but at this point I'm not sure which one could help me the most. I have 4 sets of data, 1 test and 3 different sets of controls. The measurements are binary, with a matrix of 0 and 1 I'm measuring across time (rows, ~815) the behaviour of organelles in the cell by microscopy in response to different stimuli (several measurements
2009 Sep 28
2
re trieve user input from an tcl/tk interface
Hello everyone, this is my first post here and I hope I signed up correctly and someone will take me by the hand and help me out. I am new to R and cannot figure out what to do here... ... I want to have an User Interface that requests input. I want to save this input to a variable to use it later on. I was able to do this with a modalDiaglog (
2011 Dec 08
1
prop.test() and the simultaneous confidence interval for multiple proportions in R
Dear list members, I want to perform in R the analysis "simultaneous confidence interval for multiple proportions", as illustrated in the article of Agresti et al. (2008) "Simultaneous confidence intervals for comparing binomial parameter", Biometrics 64, 1270-1275. If I am not wrong the R function implementing the Agresti et al. method is prop.test(). I ask an help because I
2012 Mar 25
2
Multivariate function from univariate functions
I'm relatively new to R and I'm stuck. I'm trying to construct a surface to optimize from a multivariate dataset. The dataset contains the response of a system to various stimuli. I am trying to optimize the mix of stimuli to maximize the response. To do so, I've interpolated the various datasets of type response vs. stimuli and I now have an array of functions
2005 Dec 21
6
Writting 0s
Hello zfs-discuss, When compression is set to on for a givef file system, then if block contains only 0s "nothing" is writen. I wonder if it would be beneficial if ZFS behaves that way not only for block which are going to be compressed but for all block regardless of compression. Or perhaps making this simple check would too much impact CPU for normal data? ? --
2013 Apr 26
1
prcomp( and cmdscale( not equivalent?
Hello, I have a dilemma that I'm hoping the R gurus will be able to help resolve. For background: My data is in the form of a (dis)similarity matrix created from taking the inverse of normalized reaction times. That is, each cell of the matrix represents how long it took to distinguish two stimuli from one another-- a square matrix of 45X45 where the diagonal values are all zero (since this
2012 Dec 02
1
Repeated-measures anova with a within-subject covariate (or varying slopes random-effects?)
Dear all, I am having quite a hard time in trying to figure out how to correctly spell out a model in R (a repeated-measures anova with a within-subject covariate, I guess). Even though I have read in the posting guide that statistical advice may or may not get an answer on this list, I decided to try it anyway, hoping not to incur in somebody's ire for misusing the tool. For the sake of
2006 May 04
1
Finding ties in data (be)for(e) BradleyTerry
Dear all, I have carried out a pairwise comparison study that I want to analyze using the BradleyTerry package to establish a rank order of my stimuli. However, BT does not handle ties between stimuli, so I need to find those in my data before I can use that model. The code below goes from the format of my result file(s) to a data frame suitable for BT, but as you can see, there are some ties. I
2004 Jan 16
0
anova repeated measure interpretation
Dear all, I have tried to use R for the repeated measures experiment design in a phonetic study, and in the resulting forms I met some problems which perturb the final interpretation of the results. I will explain the experiment design first: the same 7 subjects were answering a question about 25 linguistic stimuli; the stimuli were the same utterances which were processed in 3 different ways (3
2011 Jan 04
1
t-test or ANOVA...who wins? Help please!
Dear all, I need an help because I don´t know how to perform the analysis in the right way, as I get different beheaviors using t-test and two ways ANOVA. In what follow I post the table, my goal and the strange results I got. I kindly ask you an help because I really don´t know how to solve this problem. So the table is this: number stimulus condition response 1
2012 Aug 03
0
MANOVA with repeated measures in R
Dear list member, I deperately need an help in performing a MANOVA in R, but I encountered some problems both in the design and in the synthax with R. I conducted a listening experiment in which 16 participants had to rate the audio stimuli along 5 scales representing an emotion (sad, tender, neutral, happy and aggressive). Each audio stimulus was synthesized in order to represent a
2010 Jun 09
3
comparing two regression models with different dependent variable
Hi, I would like to compare to regression models - each model has a different dependent variable. The first model uses a number that represents the learning curve for reward. The second model uses a number that represents the learning curve from punishment stimuli. The first model is significant and the second isn't. I want to compare those two models and show that they are significantly
2003 Mar 25
4
Fixed Quantizer - Fixed Quality
Here's the problem: > 2) Encoding with rate control as in single pass "Bitrate > control" will not > lead to better quality than fixed quant (with the right value > of the fixed > quant). Ratecontrol doens't know anything about "quality". It > will try to > reach more-or-less CBR. > > But somehow this is not a fair comparison, because