similar to: problem about finding power in test about variances

Hello All I am new to this list. I have a problem where for a single sample drawn from normal population, null hypothesis is that variance = k (say). Alternative hypothesis is variance > k. Now if we know the true variance, then I would like to calculate the sample size required to produce certain power (for some significance). How do I do this ? I thought of using pwr.chisq.test, and I

Craig, Thanks for your follow-up note on using the asypow package. My problem was not only constructing the "constraints" vector but, for my particular situation (Poisson regression, two groups, sample sizes of (1081,3180), I get very different results using asypow package compared to my other (home grown) approaches. library(asypow) pois.mean<-c(0.0065,0.0003) info.pois <-

Dear all, I've been delighted to just notice that Cohen's formulas for Effect Size 'w' and the associated power have been implemented in the 'pwr' package (thanks to St?phane Champely and others).. There is one aspect, though, that perplexes me. I'm doing some last minute post hoc analyses, meaning that my sample size (N=3404) has been long fixed, and I'm

Hi all, I'm having trouble getting access to the pwr. This is on Ubuntu Lucid Lynx, 64 bit. I'm installing pwr via packages.install('pwr'), and loading it via library(pwr), both of which appear successful. Strangely, I never get access to the pwr object in R. I tried installing it to /usr/local/lib/R/site-library and ~/R/x86_64-pc-linux-gnu-library. I also tried installing it

Full_Name: Michael J. Lew Version: R version 2.9.1 (2009-06-26) OS: OS X Submission from: (NULL) (210.49.195.149) The default function power.t.test gives inaccurate values, particularly with large sig.level. There are two reasons for me to propose that power.t.test is inaccurate: 1. When sig.level approaches 1, so should the power. However,

dear all, in the package pwr , there is the fonction power.anova.test which permit to obtain the power for a one-way ANOVA...but I'm looking for a way to compute the power of a multiway ANOVA.( find the 1-beta). Is it possible? do you have some ideas ? regards [[alternative HTML version deleted]]

Dear R experts, I have conducted a power calculation in order to estimate the number of subjects needed to detect an effect size of d=0.28 (cohen's d) for a difference between two independent groups (alpha level should be 0.05 and the effect should be detected with 80% probability). The results from the code below indicates that I would need n=400 subjects (200 in each group). This is seems

I have an unbalanced design I would like to run a power analysis on. What I have been able to find has pointed me to using the pwr.f2.test function as described below. My problem is that I don't know how to appropriately define the numerator and demoninator df. If someone can help here is some more info about my design. It is an unbalanced 2^3 x 3 design where the factor with 3 levels is a

On 12/22/2014 05:11 PM, Vince Hsu wrote: > The platform device does not use the common nouveau_pwr_init() to initialize > the PWR, but it does need the .prob() be assigned to avoid NULL pointer > dereference in graph/nve4.c. s/prob/pgob/ :-( Will fix in next version. > > Signed-off-by: Vince Hsu <vinceh at nvidia.com> > --- > > v2: this patch is added since v2. (v1

Dear all, my colleague (a statistician - not yet using R) aked me, if there is a R package comparable to the software "PASS" (Power Analysis and Sample Size Procedures), comprising about 150 procedures. I found the R package "pwr". Are there other (more comprehensive) power analysis packages? Many thanks! Udo

Hello, I've encountered a very weird issue with the method subset(), or maybe this is something I don't know about said method that when you're subsetting based on the columns of a data frame you can only use constants (0.1, 2.3, 2.2) instead of variables? Here's a look at my data frame called 'ea.cad.pwr': *>ea.ca.pwr[1:5,] MAF OR POWER 1 0.02 0.01 0.9999 2 0.02

I'm trying to join a Samba 3.0.4 (compiled from source on Debian) to an Active Directory as a member server. I believe Kerberos is configured correctly as kinit creates a ticket for the realm. Executables appear to have support for Kerberos and LDAP (smbd -b | grep KRB and grep LDAP) return OK. When I try to join the AD with net ads join -U myadminusername I'm prompted for my

Hello guys, I've prepared a patch based on my findings for the bbswitch module (https://github.com/Lekensteyn/acpi-stuff/tree/master/bbswitch). This adds a proper check whether a _DSM function is supported or not and make OFF / ON for vga_switcheroo work for nVidia Optimus models. The patch is based against the mainline kernel. It has been tested on my Clevo B7130 laptop running kernel 3.2

Hi, I am trying to sort out a discrepancy between power calculations results between me and another statistician. I use R but I am not sure what she uses. It is on the proportions test and so I have been using pwr.prop.test. I think I have tracked the problem down to pwr.prop.test not using the continuity correction for the test (I did this by using the java applet from

SSweibull() :  problems with step factor and singular gradient Hello I am working with growth data of ~4000 tree seedlings and trying to fit non-linear Weibull growth curves through the data of each plant. Since they differ a lot in their shape, initial parameters cannot be set for all plants. That’s why I use the self-starting function SSweibull(). However, I often got two error messages:

Is there a library that provides power calculation and sample size estimation for nonlinear regression? The task is easy for linear regression with the "pwr" package, but I can't find a method for nonlinear regression (estimated with the "nls" package). -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- Dr. Johannes W. Dietrich, M.D. --

Hello everyone, I have a Tripp-Lite UPS (smart1500rmxl2ua) I'm trying to get working with nut. This is a FreeBSD 10.3 box. I've tried using the usbhid-ups<http://networkupstools.org/docs/man/usbhid-ups.html> driver but everytime I try to start up nut, I get this: # upsdrvctl start Network UPS Tools - UPS driver controller 2.7.4 Network UPS Tools - Generic HID driver 0.41 (2.7.4)

Hi Team, I have installed asterisk-12 Beta but when I try to asterisk start then get below issue. *[root at cs-gb-pwr-1-04 asterisk-12.0.0-beta1]# asterisk -r asterisk: error while loading shared libraries: libjansson.so.4: cannot open shared object file: No such file or directory [root at cs-gb-pwr-1-04 asterisk-12.0.0-beta1]#* -- Thanks and regards Virendra Bhati +91-9718500594

There might be some callers of nouveau_clock_astate(), and they are from inetrrupt context. So we must ensure that this function can be atomic in that condition. This patch adds one parameter which is subsequently passed to nouveau_pstate_calc(). Therefore we can choose whether we want to wait for the pstate work's completion or not. Signed-off-by: Vince Hsu <vinceh at nvidia.com> ---

Hi all, I would like to estimate power and necessary sample size for a GLM with a response variable that has a poisson distribution. Do you have any suggestions for how I can do this in R? Thank you for your help. Sincerely, Craig -- Craig A. Faulhaber Department of Forest, Range, and Wildlife Sciences Utah State University 5230 Old Main Hill Logan, UT 84322 (435)797-3892