search for: intraclass

...> -----Original Message----- > From: r-help-bounces at stat.math.ethz.ch > [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Karl Knoblick > Sent: Tuesday, May 16, 2006 6:10 AM > To: r-help at stat.math.ethz.ch > Subject: [R] Interrater and intrarater variability > (intraclass correlationcoefficients) > > Hello! > > I want to calculate the intra- and interrater reliability of > my study. The design is very simple, 5 raters rated a > diagnostic score 3 times for 19 patients. > > Are there methods/funtions in R? I only found packages to >...

...etations. All of the inputs for these calculations come from the repeated measures analysis which is described in P&B. Good luck! P. Message: 1 Date: Tue, 16 May 2006 10:09:54 +0000 (GMT) From: Karl Knoblick <karlknoblich at yahoo.de> Subject: [R] Interrater and intrarater variability (intraclass correlation coefficients) To: r-help at stat.math.ethz.ch Message-ID: <20060516100954.6267.qmail at web26504.mail.ukl.yahoo.com> Content-Type: text/plain; charset=us-ascii Hello! I want to calculate the intra- and interrater reliability of my study. The design is very simple, 5 raters rat...

Dear R-users, consider a 2-level linear mixed effects model (LME) with random intercept AND random slope for level 1 AND 2. Does anybody know how to calculate Intraclass-coefficient (ICC) for highest (innermost) level 2 ??? In the literature, I did not find an example for these kind of komplex models. For 1-level Random-Intercept models it would be easy: ICC = variance due to the clustering variable / (variance due to the clustering variable + variance remaining)...

Hello! I want to calculate the intra- and interrater reliability of my study. The design is very simple, 5 raters rated a diagnostic score 3 times for 19 patients. Are there methods/funtions in R? I only found packages to calculate interrater variability and intraclass correlation coefficients for matrices of n*m (n subjects, m raters) - I have n subjects, m raters and r repetitions. Can anybody help? Thanks! Karl

Hi, Can R calculate an intraclass correlation coefficient for clustered data, when the outcome variable is dichotomous? By now I calculate it by hand, estimating between- and intracluster variance by one-way ANOVA - however I don't feel very comfortable about this, since the distributional assumptions are not really met.... May...

...3 experiment combinations), for 167 subjects, each one has answered the same question twice (out of a bunch of "types" of questions). Each answer could get an integer number between 0 to 3. I wish to combine the two answers, but first to be sure I could, I would have liked to run an ICC (Intraclass correlation) check on the two answers. Naturally, I would use the irr, condord, or psy packages (as John Fox suggested back then), but I can't because of the repetitions of different design question for each patient. Since the mentioned packages (irr, condord, and psy) Can take only a n*m matri...

...number of rows: 1700, 1750 I've looked at the data in the file and it seems to be okay. Any thoughts would be much appreciated. I'm getting used to R so if possible, I would really appreciate an easy to understand answer! -- View this message in context: http://r.789695.n4.nabble.com/ICC-IntraClass-Correlation-Error-tp4088036p4088036.html Sent from the R help mailing list archive at Nabble.com.

Hi, all There are 62 samples in my data and I tested 3 times for each one, then I want to use ICC(intraclass correlation) from irr package to test the consistency among the tests. *combatexpdata_p[1:62] is the first text results and combatexpdata_p[63:124] * is the second one and *combatexpdata_p[125:186]* is the third. Here is the result: result<-icc(cbind(combatexpdata_p[1:62],combatexpdata_p[63:12...

I have a spectrophotometric dataset with repeated measures of a value at 200 wavelengths for each of 150 individuals. I would like to use the repeated samples to at each wavelength to look at measurement/observer error, compared to difference between individuals error I have looked at doing this with icc{irr} or using an anova approach, but I am unclear how to acheive this given that there

...om 90 subjects. Each of the 4 statements receives one of three responses (say -1, 0, or 1). I can use Cramer's V or Spearman correlations to assess the correlation between each pair of statements, but I am looking for a measure of coherence across/among all 4 statements. To me, this seems to be intraclass correlation. So I was wondering whether I can apply it here (specifically, ICC(2,1) or ICC(3,1)) or whether I should use an alternative procedure given that my responses are ordinal. I am grateful for your tips, Daniel ----------------------------------------------- "Who has visions should s...

...l model: Y_ijk = mu + a_i + b_j(i) + e_k(j(i)) lme computes estimates of the variances for a, b, and e, call them v_a, v_b, and v_e, and I can use the intervals function to get confidence intervals. My understanding is that these intervals are probably not that robust plus I need intervals on the intraclass correlation coefficients: v_a/(v_a + v_b + v_e) and (v_a + v_b)/(v_a + v_b + v_e). I would like to use a bootstrap or a jackknife estimate of these confidence intervals. Is there any package available? I've tried to write the R code myself but I'm not sure if I understand exactly how t...

Hi, I have been working with a mixed effects model in R where I have a lot of fixed effects with a lot of variables. When I use the summary command I can only view the end of the output with the intraclass correlations and distribution of residuals. I need to be able to see the summary table at the top of the output. Is there a way to display an entire output? Thanks for the help, Foresterman

Hello R users: I am fairly new to R and am trying to figure out how to compute an intraclass correlation (ICC) and/or design effect for binary data? More specifically, I am trying to determine the amount of clustering in a data set - that is, whether certain treatment programs tend to work with more or less severe clients. The outcome variable is dichotomous (low severity / high severity...

...of 24 web sites. (each rater rated each site once). I want to come up with a measure of reliability of the ratings for the web sites ie to what extent does each rater give the same (or similar) rating to each web site. My idea was to fit a random effects model using lme and from that, calculate the intraclass correlation as a measure of rater reliability. So I analysed it using a two-factor, unreplicated random effects model, with sitenumber and rater as crossed random effects. The call to lme was: fit <- lme(score ~ 1, random=list(level=pdBlocked(list(pdIdent(~sitenumber-1), pdIdent(~rater-1)))),da...

...bootstrap. Ultimately, I am interested in using median regression to model changes in the outcome variable over time. Summary.rq's robust variance estimator is not applicable to repeated-measures data. I question whether the block (cluster) bootstrap variance estimator, which can accommodate intraclass correlation, would perform well. Can anyone suggest alternatives for variance estimation in this situation? Regards, Jim James W. Shaw, Ph.D., Pharm.D., M.P.H. Assistant Professor Department of Pharmacy Administration College of Pharmacy University of Illinois at Chicago 833 South Wood Street,...

...; [1] 0 0 $"5" [1] 0.385000000 0.006100706 $"6" [1] 2.6550000000 0.0004999122 $"7" [1] 0.0650000 0.0013005 $"8" [1] 0.375000000 0.008499472 $"9" [1] 0.5800 0.0002 $"10" [1] 3.9000 0.0338 Now, how do you use (lme in) R to compute the Intraclass correlation for these data? I have written brute-force code to get the "right" answer, but I cannot get the proper mean squares from any regression model I have tried. It seems like it should be trivial, but I cannot do it! I need this to work in order to apply the technique to a much l...

...I've tried including the cluster ID as a factor in the model formula, but the default response is to try and estimate the unique effect of each cluster, which given 1000 clusters is impossibly time consuming. What I want instead is an estimate of the variance due to clusters, or perhaps an intraclass correlation, and cluster-adjusted standard errors for the effects of other variables in the model. I expect I can account for clustering by using lme with clusters as a random effect, but then I can't use the flexible smooths available in gam. If it's not possible to get both clusterin...

Hi, I'm essentially wanting to calculate intra- and inter-observer variabilities for the first principal component of an optic disc shape measure of a sample of individuals, so from what I can work out I need to work out an intraclass correlation coefficient(s). For the intra-data, I have 2 measurements taken on each individual by the same observer. For the inter-data, 2 observers have taken one measurement each on the sample. I've found the 'icc' function in the {psy} package, but am not sure how I'd perform t...

Hi R users: Is there a function to obtain the correlation within groups from this very simple lme model? > modeloMx1 Linear mixed-effects model fit by REML Data: barrag Log-restricted-likelihood: -70.92739 Fixed: fza_tension ~ 1 (Intercept) 90.86667 Random effects: Formula: ~1 | molde (Intercept) Residual StdDev: 2.610052 2.412176 Number of Observations: 30 Number

I am helping someone calculate ICC using R. I know R has several packages like irr, psy etc which provide options to calculate ICC (intraclass correlation coefficient). When getting ICC, we need to use the model: two-way mixed model with absolute agreement. I only found that in irr package, it provides the option of choosing one or two way and consistence or absolute agreement model. However, there is no parameter which allows me to cho...