Fuck me that's correct. :( So we do need the sort to actually be "for each", instead of random. Would you guys say this is a bug, or that a feature request for making sort use a unique random value instead of an arbitrary one?
On 23.05.2013, at 06:20, Dar Scott wrote: > Easy mistake to make, Jacques, but it is not 3!. > > Random() emulates independent random numbers. It cannot avoid numbers > returned before in the sort. Each line will get a randomly assigned number > independent of the other lines. > > The number of ways 3 lines can be ordered does not apply. > > Each line will be assigned a number by random(). So it is possible that the > first line will be assigned a 2 and the other lines assigned 2, also. The > probability of that is one out of 3^3. (Not three factorial) > > You can create a function to log the assignments and use that as the > comparison metric function. You can see the assignments, and different lines > can have the same value. > > Each sort will get a random pattern of 1, 2 and 3. There are 27 of them. > > Fourteen of them will cause a sort with the first line coming first again. > That is 52%, not 33%. > > You can write code to sort the same starting string a thousand times and the > same first line will show up 52% of the time, not 33%. > > Dar > > On May 22, 2013, at 6:16 PM, Jacques Hausser wrote: > >> Dar, >> >> I'm afraid you are wrong… >> they would not be 27 possibilities (3^3) but only 6 (3! - factorial), >> because each line (first, second and third) can only be present once. >> >> And I tested random (3) and random (9999) corrected to give a number between >> 1 and 3 with the following scripts: >> >> on mouseUp >> put "" into fld "FR" >> repeat 100 >> put random(3) & comma after fld "FR" >> end repeat >> end mouseUp >> >> result: >> 1,3,2,3,1,1,1,3,3,3,3,2,1,2,2,2,1,2,2,3,1,3,2,3,2,2,3,2,2,3,3,2,2,3,1,3,1,3,2,2,1,3,2,1,3,3,2,3… >> mean value: 1.992 >> >> on mouseUp >> put "" into fld "FR" >> put 0 into tt >> repeat 1000 >> put random(9999) into tx >> switch >> case tx <= 3333 >> put 1 into t >> break >> case tx <= 6666 >> put 2 into t >> break >> default >> put 3 into t >> end switch >> add t to tt >> end repeat >> put tt/1000 into fld "Moyenne" >> end mouseUp >> >> result: >> 1,2,3,3,1,3,2,3,3,2,3,2,3,3,2,2,1,1,3,3,2,2,2,1,3,1,3,3,3,3,1,1,3,2,3,1,2,1,1,1,2,1,3,2,3,2,2… >> mean value: 1.992 >> >> so, it seems to be no statistical difference in the results ! No reason to >> use large numbers when not needed. (Ideally, the means should be 2, not >> 1.992, but well…) >> >> Jacques >> >> >> Le 23 mai 2013 à 01:23, Dar Scott <d...@swcp.com> a écrit : >> >>> Here is (I think) the situation for random(3). >>> >>> Lines will be (virtually) assigned numbers randomly; there are 27 >>> possibilities. >>> >>> There are 9 cases in which the first line is assigned a 1. It is first in >>> the sort. >>> There are 4 cases in which the first line is assigned a 2 and the other >>> lines get 2 or 3. It is first in the sort >>> There is one case in which all get a 3. Again, the first line comes in >>> first. >>> >>> So, assuming my math is good, that means the first line comes in first 14 >>> out of 27 times. That is 52% and should match what people are getting >>> empirically. >>> >>> This doesn't address broken random(), though. It just emphasizes the >>> importance of the big number for random(). >>> >>> Dar >>> >>> >>> On May 22, 2013, at 11:59 AM, Chris Sheffield wrote: >>> >>>> I have a list of three words that I need to be randomly sorted. To start >>>> with, the first word is the correct answer to a question. I want to >>>> re-order the list so that the correct answer may be the second or third >>>> word, and not necessarily the first. How can I do this successfully every >>>> time? The docs give an example like this: >>>> >>>> sort lines of myVar by random(the number of lines of myVar) >>>> >>>> But this only seems to work successfully one time. After that, the list is >>>> always set so the first word is the correct answer. So then I tried >>>> randomly setting the randomSeed value, since this value is supposed to >>>> affect the random() function and the any keyword, but this didn't seem to >>>> make much difference except to change it so either the second or third >>>> word is *always* the right answer. I need it to be more mixed up than that. >>>> >>>> So does anyone have a good way to do this? >>>> >>>> Thanks, >>>> Chris >>>> >>>> >>>> -- >>>> Chris Sheffield >>>> Read Naturally, Inc. >>>> www.readnaturally.com >>> >>> >>> _______________________________________________ >>> use-livecode mailing list >>> use-livecode@lists.runrev.com >>> Please visit this url to subscribe, unsubscribe and manage your >>> subscription preferences: >>> http://lists.runrev.com/mailman/listinfo/use-livecode >> >> >> >> _______________________________________________ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your subscription >> preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode > > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode -- Use an alternative Dictionary viewer: http://bjoernke.com/bvgdocu/ Chat with other RunRev developers: http://bjoernke.com/chatrev/ _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
