similar to: Homework help: t test hypothesis testing with summarized data?

Displaying 20 results from an estimated 120 matches similar to: "Homework help: t test hypothesis testing with summarized data?"

2013 Jan 04
4
Iterative loop using "repeat"
Hi, I'm Marianna I'm trying to apply the command "repeat" to my matrix but the repeat process doesn't work as I would. In particular I would like to apply the function robustm () _that I have created_ to my two matrices, if the difference between the two matrices is less than 0.001, R give me back the last matrix. The code thus created allows me to repeat the process only
2012 Sep 16
1
How to plot two lines, and only one line with errorbar by qqplots of R
Here is my code, which plots three lines with errorbar. How could I add an extra line without errorbar to the plot? Thank you very much. beta.data <- data.frame ( method = rep(c("Wrong", "Correct", "Full Bayes"), each = T_obs), mean.beta = c(mean.beta1, mean.beta2, mean.beta3), t = rep(points, 3), std.beta = c(std.beta1, std.beta2, std.beta3) ) limits =
2006 Jul 03
1
San Andreas and ATI graphic card :/
Hi, I'm using Ubuntu Dapper and I'm trying to emulate GTA San Andreas. Unfortunately, I have ATI Radeon 9600 PRO :( . (I've got the newest drivers 8.26.18) When I'm running Wine, this game starts and works only for a couple of seconds :/ It shows logo of San Andreas, and after that it crashes. Wine shows this bug: fixme:system:SystemParametersInfoW Unimplemented action: 8193
2010 Aug 18
5
Linear regression equation and coefficient matrix
Hi, I have 20*60 data matrix (with some NAs) and I wish to perfom a Pearson correlation coefficient matrix as well as simple linear regression equation and coefficient of determination (R2) for every possible combination. Any tip/idea/library/script how do to so. Thanks, As hz -- View this message in context:
2007 Oct 30
3
Homework help: Is this how CI using t dist are constructed?
I'm trying to replicate some of the examples from my textbook in R (my text uses Minitab). In this problem, I'm trying to construct a 95% confidence interval for these distance measurements [1]: > # Case Study 7.4.1, p. 483 > x <- scan() 1: 62 52 68 23 34 45 27 42 83 56 40 12: Read 11 items > alpha<-.95 > mean(x) + qt(c((1-alpha)/2, 1-((1-alpha)/2)), df=length(x)-1) *
2009 Dec 11
1
Sources for open sourced homework questions for R?
Hi, I am teaching a one month class in applied statistics and want to bring my students up to speed in R without devoting much/any lecture time to R instruction. I think that the best way to do this is to provide them with a lot of R questions for homework. These questions would be numerous (there is a lot of material to cover), go from very simple to somewhat complex, and focus on all the
2007 Oct 31
3
Homework help: Is this how CIs of normal distributions are computed?
I'm looking for a function in R similar to t.test() which was generously pointed out to me yesterday, but which can be used for normally distributed data. To recap yesterday: > x <- scan() 1: 62 52 68 23 34 45 27 42 83 56 40 12: Read 11 items > alpha<- .05 > t.test(x) One Sample t-test data: x t = 8.8696, df = 10, p-value = 4.717e-06 alternative hypothesis: true
2011 Jan 26
3
Need help with my homework
Hello to all again :) Again, I have an issue with my homework. I was troubling myself for two days, and I still can't get it :( So, if someone can help me, I would be so grateful... HOMEWORK 1. I need to draw function, random walk take the length of walk, and its in 2D. As a result, I have to take matrix in which are i-lines of matrix, written coordinates on i-steps radnom.walk <-
2012 Sep 10
2
how to create a segplot in black and white?
Hi to all I hope you can help me. # I'm trying to plot the following ratio data with standard error bars (horizontal). ratioBiomass <- c(1.327, 0.865, 1.900, 0.992, 1.469, 1.381, 1.230,1.269, 2.411, 1.288, 1.861, 0.714, 1.341, 1.362, 1.065, 2.374) SEratio <- c(19.28, 5.04, 0.01, 0.01, 0.90, 0.02, 0.002, 11.37, 0.004, 0.29, 0.003, 0.13, 0.21, 0.52, 1.66, 14.57) Species <-
2007 Oct 04
1
comparing matched proportions using glm
Dear R users, Is it possible to use a generalized linear model to do a binomial comparison of one list of proportions with a matched list of proportions to test for a difference? So, for example: list 1 list 2 a1 | b1 a2 | b2 3 | 4 7 | 9 6 | 7 5 | 1 9 | 1 3 | 1 I want to compare list 1 with list 2 and the samples
2006 Jun 05
1
Survey - twophase
Dear WizaRds, I am struggling with the use of twophase in package survey. My goal is to compute a simple example in two phase sampling: phase 1: I sample n1=1000 circuit boards and find 80 non functional phase 2: Given the n1=1000 sample I sample n2=100 and find 15 non functional. Let's say, phase 2 shows this result together with phase 1: ...................phase1........
2010 Nov 16
2
Vectors out of lists?
Hello there I have a list, Y, and each component of that list is a real-valued function (that is, Y[[i]](u) returns a number). I was wishing to build the mean function and the first thing I thought of was Ybar<-function(u){ mean(Y[[1:n]](u)) } but obviously this doesn't work, since Y[[1:n]] is not allowed at all. Any elegant suggestions? I really would like to avoid something like
2008 Jul 20
4
drawing segments through points with pch=1
Please excuse me for asking such basic questions: Here is my code > y=c(1.21,0.51,0.14,1.62,-0.8,0.72,-1.71,0.84,0.02,-0.12) > ybar=mean(y) > ll=length(y); > ybarv=rep(ybar,ll) > x=1:ll > plot(x,ybarv,pch=1) > segments(x[1],ybar,x[ll],ybar) What I get is a collection of small circles, with a segment "on top" of the circles, which is almost what I want. But I
2008 Jul 20
3
asp and ylim
#See David Williams' book "Weighing the odds", p286 y <- c(1.21, 0.51, 0.14, 1.62, -0.8, 0.72, -1.71, 0.84, 0.02, -0.12) ybar <- mean(y) ylength <- length(y) ybarv <- rep(ybar, ylength) x <- 1:ylength plot(x,y,asp=1,xlab="position",ylab="ybar",type="n",ylim=c(-1,1)) segments(x[1], ybar, x[ylength], ybar) segments(x,ybarv,x,y)
2011 Jun 03
2
Y error bars, dates on the X-axis
Dear forum, Does anyone know any functions for plotting vertical error bars, if the x-axis variable is a date? I can produce a pretty plot with dates on the x-axis, if I don't want to include error bars. I can also produce a nice plot with error bars, if I just use Julian days for the x-axis, but I'd much rather have the actual dates. I have tried writing my own function, plotCI
2008 Sep 06
2
Hopefully an easy error bar question
Hi im trying to add error bars to my barplots, there very basic, i have a few grapghs where the y variable is different but on all the X variable is Age (Adult and Juvenile) however this is split into two levels so i have males and females, so my graph basically has four bars on it. I know how to add eror bars for instance when there is only one level eg lookng at the diffrence between male and
2011 Apr 01
0
[LLVMdev] Proposal for improving llvm.gcroot (summarized)
>> if (cond) { >>  llvm.gc.declare(foo, bar); >> } >> ... >> // foo may or may not be a root here >> ... >> if (cond) { // same condition as above >>  llvm.gc.undeclare(foo); >> } >> > You would need to do the same as what is done today: Move the declare > outside of the condition, and initialize the variable to a null state, such
2017 Oct 08
0
Discourage the weights= option of lm with summarized data
Ah, I think you are referring to this part from ?lm: "(including the case that there are w_i observations equal to y_i and the data have been summarized)" I see; indeed, I don't think this is what 'weights' should be used for (the other part before that is correct). Sorry, I misunderstood the point you were trying to make. Best, Wolfgang -----Original Message----- From:
2017 Oct 07
1
Discourage the weights= option of lm with summarized data
In the Details section of lm (linear models) in the Reference manual, it is suggested to use the weights= option for summarized data. This must be discouraged rather than encouraged. The motivation for this is as follows. With summarized data the standard errors get smaller with increasing numbers of observations. However, the standard errors in lm do not get smaller when for instance all weights
2007 Sep 25
2
Need help with function writing
Hello: If anyone could guide me with this I would greatly appreciate it. Thanking you in advance for your assistance. Using a 3-level input factor alternative so that a function(below) can compute both a two-sided and one-sided p-values. Making the two-sided test the default. And produce output information about which alternative was tested. Where would I place the ifelse statement?