Hi, thank you both for your replies, I really appreciate it!
To Mike: yes, random integers. Can I use the function round() as in the example with 5 random numbers below? To Billy: for the second part I got an error, but it may be that I didn't properly set "i"...? Here is the R output: x <- runif(60 , 0 , 10) # 60 numbers from 0 to 10 > x [1] 3.29208009 8.62643979 3.40762875 0.35224714 6.78760173 4.72160818 etc y<- runif(60, 15 , 25) # same as above , from 15 to 25 > y [1] 18.48391 24.44361 23.20955 16.61257 23.06074 17.71158 23.67585 19.31675 etc i <- 12 > i [1] 12 > for( i in 1:length(x)) { + z = x[i] + y[i] + return z} Errore: unexpected symbol in: "z = x[i] + y[i] return z" To all: I attach an example with only 5 random numbers step 1. random number generation x <- round(runif(5 , 0 , 10) ) < x [1] 2 1 0 6 8 y <- round(runif(5 , 15 , 25) ) > y [1] 21 24 22 22 19 step2. matching of numbers from x and y to create lotteries lottery 1: 2$ with 50% probability vs. 21$ with 50% of probability (Expected value: 2*0.5+21*0.5=11.5) lottery 2: 1$ with 50% probability vs. 24$ with 50% of probability (Expected value: 1*0.5+24*0.5=12.5) lottery 3: 0$ with 50% probability vs. 22$ with 50% of probability (Expected value: 0*0.5+22*0.5=11) lottery 4: 6$ with 50% probability vs. 22$ with 50% of probability (Expected value: 6*0.5+22*0.5=14) lottery 5: 8$ with 50% probability vs. 19$ with 50% of probability (Expected value: 8*0.5+19*0.5=13.5) step 3. Form step 2, I know that the min EV of these lotteries is 11 and the max EV is 14. The difference is: max EV - min EV = 3. I need a difference of 5 How to do this? Valeria 2012/4/29 billy am <wickedpu...@gmail.com>: > Interesting set of question.. I am completely new to R but let me try my > luck. > > Random number in R > > x <- runif(60 , 0 , 10) # 60 numbers from 0 to 10 > y<- runif(60, 15 , 25) # same as above , from 15 to 25 > > The second part though. Do you mean , > > for( i in 1:length(x)) { > z = x[i] + y[i] > return z > } > > something like that? No idea about the third part though. > > regards > Billy > > On Sun, Apr 29, 2012 at 9:29 AM, Mike Miller <mbmille...@gmail.com> wrote: >> >> On Fri, 27 Apr 2012, Vale Fara wrote: >> >>> I am working with lotteries and I need to generate two sets of uniform >>> random numbers. >>> >>> Requirements: >>> 1) each set has 60 random numbers >> >> >> random integers? >> >> >>> 2) random numbers in the first set are taken from an interval (0-10), >>> whereas numbers in the second set are taken from a higher interval >>> (15-25) >> >> >> Depends on if you mean integers. R has functions. Here's one: >> >> http://www.astrostatistics.psu.edu/su07/R/html/stats/html/Uniform.html >> >> >> >>> 3) numbers generated in the first set should be matched to numbers in >>> the second set (row by row) so that the expected value of each couple >>> of random numbers (i.e. of each lottery) is around to a given value >>> (12.5 +/- 5, where 12.5 is the median value of the interval extremes). >> >> >> Do you mean that the mean for the pair of numbers must be between 7.5 and >> 17.5, inclusive? That means the sum must be from 15 to 35. Well, you are >> in luck because if you make the numbers as you suggested above, that will >> happen -- you don't have to do anything special to make it happen. >> >> >> >>> For the computation of the expected value, the probabilities in each >>> lottery are ½ and ½. >> >> >> For what outcome? You lost me. >> >> >> >>> How do this? Any help given would be greatly appreciated. >> >> >> I hope that helps. >> >> Mike >> ______________________________________________ >> R-help@r-project.org mailing list >> 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. >> > > > > -- > http://use-r.com - R Statistics Scripting & Programming Language Online > Community Home > http://bam.domainpool.com - Domains For Sale > http://SQLHack.net - Tech Blog/Tutorials > > ------------------------------------------------------------------------------------ > > MCSA (Security) , MCSA , CCNA , LPIC - Lvl 1 , Security+ , Network+ , A+ ______________________________________________ R-help@r-project.org mailing list 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.