Re: [R] [EXT] Theta from negative binomial regression and power_NegativeBinomiial from PASSED
Hi John, the negative binomial is a tricky one - there are several different parameterisations and therefore different interpretations of the parameters. Joseph Hilbe wrote a whole book on it that might be wroth checking. Cheers, Andrew -- Andrew Robinson Chief Executive Officer, CEBRA and Professor of Biosecurity, School/s of BioSciences and Mathematics & Statistics University of Melbourne, VIC 3010 Australia Tel: (+61) 0403 138 955 Email: a...@unimelb.edu.au Website: https://researchers.ms.unimelb.edu.au/~apro@unimelb/ I acknowledge the Traditional Owners of the land I inhabit, and pay my respects to their Elders. On 15 Sep 2023 at 11:52 AM +1000, Sorkin, John , wrote: External email: Please exercise caution Colleagues, I want to use the power_NetativeBinomial function from the PASSED library. The function requires a value for a parameter theta. The meaning of theta is not given in the documentation (at least I can�t find it) of the function. Further the descriptions of the negative binomial distribution that I am familiar with do not mention theta as being a parameter of the distribution. I noticed that when one runs the glm.nb function to perform a negative binomial regression one obtains a value for theta. This leads to two questions 1. Is the theta required by the power_NetativeBinomial function the theta that is produced by the glm.nb function 2. What is theta, and how does it relate to the parameters of the negative binomial distribution? Thank you, John [[alternative HTML version deleted]] [[alternative HTML version deleted]] __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] [EXT] Downloading a directory of text files into R
Hi Bob, there may be more efficient ways to go about it but I would use R to scrape the contents of http://home.brisnet.org.au/~bgreen/Data/Hanson1/ http://home.brisnet.org.au/~bgreen/Data/Hanson2/ in order to form the URLs of the files, and then loop over the URLs. Cheers, Andrew -- Andrew Robinson Chief Executive Officer, CEBRA and Professor of Biosecurity, School/s of BioSciences and Mathematics & Statistics University of Melbourne, VIC 3010 Australia Tel: (+61) 0403 138 955 Email: a...@unimelb.edu.au Website: https://researchers.ms.unimelb.edu.au/~apro@unimelb/ I acknowledge the Traditional Owners of the land I inhabit, and pay my respects to their Elders. On 26 Jul 2023 at 8:07 AM +1000, Bob Green , wrote: External email: Please exercise caution Hello, I am seeking advice as to how I can download the 833 files from this site:"http://home.brisnet.org.au/~bgreen/Data; I want to be able to download them to perform a textual analysis. If the 833 files, which are in a Directory with two subfolders were on my computer I could read them through readtext. Using readtext I get the error: > x = readtext("http://home.brisnet.org.au/~bgreen/Data/*;) Error in download_remote(file, ignore_missing, cache, verbosity) : Remote URL does not end in known extension. Please download the file manually. > x = readtext("http://home.brisnet.org.au/~bgreen/Data/Dir/()") Error in download_remote(file, ignore_missing, cache, verbosity) : Remote URL does not end in known extension. Please download the file manually. Any suggestions are appreciated. Bob __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] [EXT] How to calculate the derivatives at each data point?
Try something like with(df, predict(smooth.spline(x = altitude, y = atm_values), deriv = 1)) Cheers, Andrew -- Andrew Robinson Chief Executive Officer, CEBRA and Professor of Biosecurity, School/s of BioSciences and Mathematics & Statistics University of Melbourne, VIC 3010 Australia Tel: (+61) 0403 138 955 Email: a...@unimelb.edu.au Website: https://researchers.ms.unimelb.edu.au/~apro@unimelb/ I acknowledge the Traditional Owners of the land I inhabit, and pay my respects to their Elders. On 31 Jan 2023 at 8:17 PM +1100, konstantinos christodoulou , wrote: External email: Please exercise caution Hi everyone, I have a vector with atmospheric measurements (x-axis) that is obtained/calculated at different altitudes (y-axis). The altitude is uniformly distributed every 7 meters. For example my dataframe is: df <- dataframe( *altitude* = c(1005, 1012, 1019, 1026, 1033, 1040, 1047, 1054, 1061, 1068), *atm_values* = c(1.41, 1.40, 1.39, 1.38, 1.37, 1.37, 1.38, 1.36, 1.33, 1.31) ) How can I find the derivatives of the atmospheric measurements at each altitude? I look forward to hearing from you! Thanks, Kostas [[alternative HTML version deleted]] __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.