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I have a list of 20 values. The first time through a loop I want to find the mean and stnd.dev. of the first two values; the second time through the loop I want to find the mean and stnd. dev. of the first 3 values, etc. until the last time through the loop I want to find the mean and stnd. dev. of all 20 values, so I end up with 19 means and stnd. deviations. How would I construct such a loop?

I've created a short program to print a table of learning curve factors. However, I cannot figure out how to format the table to: 1) Get rid of the [1]s in the first column and replace it with the values of N. 2) Line up the first row with the factors (decimal fractions). Thanks for any help. The complete program and output is as follows: > Lc<-seq(0.70,0.95,0.05) #Specify learning

Hi! I'm an R newbie and this should be a trivial problem, but I can't make it work and cannot find what I'm doing wrong in the literature. I entered the the command: table<-data.frame(x, scientific=F, digits=4) table This prints a column of x with 16 useless decimal places after the decimal point. Also, it prints an unwanted index number (1-20) in the left column. How do I get rid

I'm a new user and am having trouble with loops. In the following, I'm trying to add the results of "test" and the loops are not working. I've simplified the loop. What am I doing wrong? Thanks! > test<-numeric(20) > tot<-numeric(20) > for(i in 1:20){test[i]<-1} > for (i in 1:20){tot[i]<-(test[i]+tot[i])} > tot [1] 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

I'm an R newbie and am trying to plot 3 vectors, say a,b,c. I have downloaded 3 R manuals and searched your forum. There are plenty of X vs Y examples, but cannot find how to plot 3, or more vectors one one graph. I'm sure I overlooked something. Thanks for any help. CHV -- View this message in context: http://www.nabble.com/Plotting-3-vectors-on-one-graph.-tp15236552p15236552.html

...is when I try to duplicate problems from textbooks, I get p-values that are much different from the examples from the literature. They are off by as much as 30% to 40%. Not even close. Using an "exact" argument doesn't change the p-value. What am I doing wrong? Thanks for any help. cvandy   Charles H Van deZande [[alternative HTML version deleted]]

When I use wilcox.test, I get vastly different p-values than the problems from Statistics textbooks. For example: The following problem comes from "Applied Statistics and Probability for Engineers", 2nd Edition, by D. C. Montgomery. Page736, problem 14.7. The problem is to compare the sample data with a population median of 8.5. The book answer is p = 0.25, wilcox.test answer is p =

...(IFPRI-Senegal))   35. recoding strings containing colons (Donald Braman)   36. Re: error: no such index at level 2 (Godmar Back)   37. please remove me from this list (Curley, Jane)   38. Re: functions to calculate t-stats, etc. for lm.fit objects?       (Marc Schwartz)   39.  Formatting a Table (cvandy)   40. Two-way ANOVA gives different results using anova(lm()) than       doing it by hand (Lars Bergemann)   41. Passing arguments to with() (Tymek Wo?od?ko)   42. Re: functions to calculate t-stats, etc. for lm.fit objects?       (Whit Armstrong)   43. #INCLUDE (Idgarad)   44. Re: Reading from Go...