search for: epidemiologist

Hi everybody, recently I had to teach a course on Cox model, of which I am not a specialist, to an audience of medical epidemiologists. Not a good idea you might say.. anyway, someone in the audience was very hostile. At some point, he sayed that Cox model was useless, since all you have to do is count who dies and who survives, divide by the sample sizes and compute a relative risk, and if there was significant censoring, use cu...

...ersion outside the sqrt(), while in rstandard.lm(), the sd is already sqrt()ed. This seems to follow stdres() in VR/MASS/R/stdres.R. Of course for the c("poisson", "binomial") families, summary(model)$dispersion is 1, so sqrt doesn't make a difference, but working with an epidemiologist, Marilia Carvalho, we wanted to map the standardised residuals of a quasipoisson null model of cases offset by log(pop.at.risk), and rstandard.glm() seemed to compress the values more than we'd have expected. Her colleague: "Valeska (L. Andreozzi) says that she has already noticed that, a...

...postings. The codes are running but only NA values are generated or I get error messages that the replacement has less row than the data has (there are about 1000 unique_id and over 4000 rows in my dataset presently). I would greatly appreciate if someone could help me. Thank you! Kathleen R. Epidemiologist Montreal, QC, Canada [[alternative HTML version deleted]]

Thank you to all who made very helpful suggestions to get started with R. Duncan Murdoch raised an excellent question, asking about my background and reason for using R. I'm an epidemiologist, applying the marginal structural models approach (inverse probability of treatment weights) in a Cox proportional hazards analysis. The statistical program which I had been using does not have functions for doing a weighted Cox analysis. Any advice pointing me in the direction of resources t...

Dear there, I am working on the NHANES survey data, and want to apply quantile regression on these complex survey data. Does anyone know how to do this? Thank you in advance, Yiling Cheng Yiling J. Cheng MD, PhD Epidemiologist CoCHP, Division of Diabetes Translation Centers for Disease Control and Prevention 4770 Buford Highway, N.E. Mailstop K-10 Atlanta, GA 30341 [[alternative HTML version deleted]]

Hi, I am using many comment lines like this # a comment line in a script. Is there any way to print comment lines when I use sink() function? Or, are there any plans to include as an option to sink() function in the near future? I would not want to use cat() function as it will look messy in the original script file. Thanks! SI __________________________________________________

...ltk parts failed to install, even when trying to do so separately. Other relevant information: MacBook Pro, 15-inch, 2.16 Ghz, 3 GB RAM, 120 GB hard drive Mac OS X 10.5.2 Any idea what's going on? Thanks in advance for any help anyone can provide. Aaron ----- Aaron Solomon Adelman, PhD Epidemiologist/statistician/computer expert E-mail: Aaron.Solomon.Adelman at gmail.com

...lp(sweep) says that the result of sweep should have the same dimensions as x, however when the result of the function is a string this is not the case. How can I coerce the result of the function to cause sweep to return an array as advertised? thanks, Peter Peter Young, MPH Surveillance Epidemiologist CDC Mozambique [[alternative HTML version deleted]]

Greetings to all, and my apologies for a question that is mostly about statistics and secondarily about R. I have just started a new job that (this week, apparently) requires statistical knowledge beyond my training (as an epidemiologist). The problem: - We have 57 food production facilities in three categories - Samples of 4-6 different foods were tested for listeria at each facility - I need to describe the presence of listeria in food (1) overall and (2) by facility category. I know that samples within each facility cannot be...

...) heif=data.frame(n,Breed, Test, Titer) x=barchart( heif[,4]~ heif[,1]| heif[,3]+ heif[,2] ,ylab="titer", layout = c(2,2), scales=list(x=list(at=c(seq(0, 60, by = 15)),tick.number=c(5), labels=c(seq(0, 60, by = 15)))) ) useOuterStrips(x) Kind regards Andrew McFadden MVS BVSc | Veterinary Epidemiologist, Investigation and Diagnostic Centre | Biosecurity New Zealand Ministry of Agriculture and Forestry | 66 Ward St, Wallaceville | PO Box 40 742 | Upper Hutt | New Zealand Telephone: 64-4-894 5611 | Facsimile: 64-4-894 4973| Mobile: 027-733-1791 | Web: www.maf.govt.nz This email message and any...

...d be welcome (b) is this realistic to do within a week or shall I revert to lattice and lose the geography? Is there a simple way to draw a map in the background? It needs to cover as far as Sweden, Spain and Greece. It can be crude, as long as Italy looks roughly like a boot that is fine. I am an epidemiologist not a geographer. Michael Dewey m.dewey at iop.kcl.ac.uk

...version.string R version 2.5.0 (2007-04-23) Package: epitools Version: 0.4-8 Date: 2007-05-10 Title: Epidemiology Tools Author: Tomas Aragon <aragon at berkeley.edu> Maintainer: Tomas Aragon <aragon at berkeley.edu> Depends: R (>= 2.1.0) Description: A package of analytic tools for epidemiologists. License: GPL version 2 or newer URL: http://www.epitools.net Packaged: Thu May 10 01:55:28 2007; Tomas Built: R 2.5.0; ; 2007-05-10 14:22:09; windows (at home) > epitab(matrix(c(227,473,74,126),2)) Warning: a final empty element has been omitted the part of the args list of 'list' be...

Dear colleagues, I'm an epidemiologist with no background in programming and just started using R a few weeks ago. I am working on the epidemiology of African sleeping sickness, and am trying to use R to perform a Monte Carlo Markov Chain analysis to estimate three unknown parameters within a model of African sleeping sickness case dete...

...different sources in different formats and has often had minimal cleaning or processing before we receive it. The data providers often provide flat files which are processed in Python and translated to database format. Our analytics team comprises machine learning specialists, biostatisticians and epidemiologists. The key responsibilities of the post are to liaise with those providing the data to help them provide it in an appropriate format and to assist in the warehousing of the data including processing and documenting the data to make it ready for the analytics team. Essential attributes are good inter...

...ethods and Kulldorff & Nagarwalla's statistic) and a focused test (Stone's Test). Bootstrap is used to estimate significance and a number of models are proposed to simulate data: permutations and Poisson, Multinomial or Neg. Binomial distributions. I hope the package will be useful to epidemiologists and statisticians involved in spatial epidemiological studies. As usual, feedback and comments are welcome. Our hope is to improve the package, so suggestions about new methods to be added are of interest. With best regards, -- Virgilio G?mez Rubio Grup d'Estad?stica espacial...

Dear R Community, I would like to announce the package "surveillance", which provides methods for the surveillance of count data time series originating from the routine collection of public health data. The package addresses epidemiologists and statisticians working with routine surveillance, but it also offers an infrastructure for developers of new detection algorithms. Implemented outbreak detection algorithms are: * Stroup et al. (1989) * Farrington et al. (1996) * A Bayesian predictive posterior approach * Time varying Poisson...

...ethods and Kulldorff & Nagarwalla's statistic) and a focused test (Stone's Test). Bootstrap is used to estimate significance and a number of models are proposed to simulate data: permutations and Poisson, Multinomial or Neg. Binomial distributions. I hope the package will be useful to epidemiologists and statisticians involved in spatial epidemiological studies. As usual, feedback and comments are welcome. Our hope is to improve the package, so suggestions about new methods to be added are of interest. With best regards, -- Virgilio G?mez Rubio Grup d'Estad?stica espacial...

Course in STATISTICAL PRACTICE IN EPIDEMIOLOGY USING R ==================================================== Tartu, Estonia, 26 - 31 May 2005 The course is aimed at epidemiologists and statisticians who wish to use R for statistical modelling and analysis of epidemiological data. The course requires basic knowledge of epidemiological concepts and study types. These will only be briefly reviewed, whereas the more advanced epidemiological and statistical concepts will be treat...

...ve proved, that the formula of the causal relationship is absolutely compatible with Einstein's Theory of Relativity and with Heisenberg's Uncertainty principle. Although this is something more for a philosopher or a physicists but not that much for a statistician, a biostatistician or an epidemiologist. The same with the derived formula of the unity of gravity and electromagnetism. Best wishes, Ilija Barukcic at t-online.de 0. Rep.

Dear R Community, I would like to announce the package "surveillance", which provides methods for the surveillance of count data time series originating from the routine collection of public health data. The package addresses epidemiologists and statisticians working with routine surveillance, but it also offers an infrastructure for developers of new detection algorithms. Implemented outbreak detection algorithms are: * Stroup et al. (1989) * Farrington et al. (1996) * A Bayesian predictive posterior approach * Time varying Poisson...