Trumpace

Why? Because it gives no sense of the skill of the player? Do you really think self rating which people have gives an accurate sense of the skill of the player? I used to think that "Advanced" was one rating which was correct a reasonable amount of times, but nowadays it seems like most intermediates prefer to use that rating.

You are south and somehow reach 6S. West leads the heart 7. [hv=n=s5342htxxxdxxcqjx&s=sakqj9haj9daxcakx]133|200|Scoring: IMP[/hv] You play low from dummy, RHO plays low! and you win the 9. Good duck RHO! Is this really the relaxed club? You cash the spade King and LHO shows out. You now draw trumps, cash three rounds of clubs ending in dummy and play a heart.. to your surprise and agony, RHO discards a diamond! Turns out LHO had led the 7 from KQ87x: fourth best. Other tables got the heart King lead and made it. Bridge is a funny game. (note: hand changed a little but the lead was the same, play was relaxed, so might not be upto your standards and this is just a story)

What was the state of the match?

Actually if Rnd is not so good, trying to mimic hand shuffling (say imperfect riffle shuffle seven times) might turn out to be a better approach than just randomizing 52 slots.

This is grossly unfair. There is nothing wrong with writing your own simulation & shuffling code in Excel, in QuickBasic or in anything else you fancy. It's good practice and very educational. The RND function is not great, but it's perfectly adequate for writing simulations. I've written my own dealer in Excel and it works fine (admittedly not very fast...). Yes, there is nothing wrong with writing your own, it is educational, but for god's sake, at least look at some of the existing well known methods to do that before coming up with your own (that is the main reason for my comment). It is a bad idea if you want use your homegrown version to prove a point and are not willing to listen to others (I assumed he had listened to JTfanclub and corrected his post output method, seems like he didn't). Also, how do you decide a shuffling algorithm is "fine"? By going over a few hands generated? The reason his shuffling algorithm appears to be ok, is that the next shuffle is done on the previously shuffled deck. So his results would actually be dependent on the number of hands he is trying to generate. Please try moving the Call start_deck line of code into the simulation loop (which should not effect the randomness of generated hands, if his shuffle code is "ok") and see the results... There are really good and free deal generators out there. It is much better to use them. Or at least if you want to write your own, follow some of the standard methods which are proven to be correct. Sorry for the bad analogy, but it is like prescribing yourself medicines when we have a perfectly good doctor who knows better. If he had followed some of the standard methods, I would not have made that (I admit, a little harsh) comment. Also, I have already apologised to him on the other thread he has started.

I did look at the code for your shuffler you posted and there seemed to be two problems: i) You are using Rnd, which is not reliable. ii) You are trying to mimic hand-shuffling by clumping no more than 4 cards and you do this only 4 times. That is the main reason for the claim that your hand shuffler is not uniformly random and that claim is not just because of the values you were getting. In fact, if you are still reading the other thread, I posted a simple test for your generator which you can try out and let us know if it matches your expectations. (I would have run it myself, but I don't have excel). Sorry if any of my posts came out as insulting. I didn't intend that in any way.

Try it out. It works. It comes up with the expected results. Anything else? Sure. Here is a simple test. Please use your shuffling algorithm to do the following simulation for me. Deal say a 100 hands (or whatever reasonable number of deals you like) Use the generator to calculate: i) the chances that West or North holds the Spade Ace. ii) the chances that East or South holds the Spade Ace. (Note West = hand 0, North = hand 1 in your code, Spade Ace = 51) For a more complex test: Do the above 100 times for say 10 hands each time and average the results.

BebopKid, looks like your shuffle algorithm isn't correct. What in the world are you trying to do writing your own shuffling code? In order to do simulations, you really need a very very good random number generator. The RND function is a really bad random number generator. Even if it was good, I don't think your shuffle function would generate deals with uniform probability. Basically, your random hand generation code is wrong.

I thought I will stay away, but BebopKid's simulation results forced me to respond. I did a simulation of my own, using Deal 3.08. Here are the results: for 5 spades with North and 4 with south with 30,000 deals these are the results: 2-2 split = 12165 (~40.55%) 3-1 split = 14971 (~49.9%) 4-0 split = 2864 (~9.54%) for 6 spades with North and 3 with south, with 30,000 deals these are the results: 2-2 split = 12231 (~40.77%) 3-1 split = 14900 (~49.66%) 4-0 split = 2869 (~9.56%) Here is the condition script used: BebopKid, please post the simulation code/method you used.

Looking at Ralph's posts I have my doubts, he seems so convinced that pavlicek or whatever his source is right that he doesn't even contemplate the fact that he might be wrong, he just laughs at Bebop for contradicting the obvious without even thinking. I also see the analogy with Galileo or Columbus the way bid_them_up does. Even if ralph is behaving as you say (which I think he is not, he is quoting sources which BebopKid cited and Pavlicek is a well known authority in these matters) it still does not falsify the statement: "Quite a number of educated people have a scientific bend of mind in online forums". It just proves that you aren't one of the ones with a scientific bend of mind, as any statistician will tell you just one example is not enough to falsify that statement. People may strongly believe whatever they want: God exists, a natural 2NT is forcing, or probabilities change depending on distribution of the 9 cards. The strength of the belief does not make them right. Sorry, this thread is getting out of hand, I think I will stop participating.

Where would we be if: Columbus has listened to "everybody"? Newton had gone on about his business like everybody else when the apple fell? The Wright Brothers had listened when told they could not fly? Kennedy had paid attention to those smarter than him who said it was impossible to put mankind on the moon? and countless other similar events in history, where somebody has stopped to question the norm. Much knowledge and advancement of mankind has come directly from asking "What if?" or not taking what is said as gospel, just because everyone says its so. Now, I said it was a "crazy" thought that possibly it might make a difference if the suit split 5-4 or 8-1. I did not claim that the current (and what I also believe to be accurate) probabilities were not accurate, I simply had an admittedly crazy "What if" thought. But while you say: I, say, maybe, just maybe when everybody else is telling you something can't be done or isn't possible, or it simply has to be that way, it might be a good time to think harder about how to go about proving them to be incorrect. Mind you, I am not saying they are incorrect. But if you always simply blindly accept statement of the sorts being made here, then advancements cease to be made. "Always listen to experts. They'll tell you what can't be done, and why. Then do it." -- Lazarus Long, Time Enough for Love (Amusing that Ralph mentions the Flat Earth society, in defense of the other sides opinion. I see it as exactly the opposite. Everybody else would be the Flat Earth Society in Columbus's time, while Bebop would be Columbus.) What you say is totally irrelevant... The problem in question has a clear mathematical proof, unlike the scientific theories of those days which did not have any proof (they were just theories, waiting to be proved/disproved). All we need to do is look at the proof. During the times you mention most people weren't scientific minded, but were just stubborn believers. The times have changed and these days the quite a number of educated people at least have a scientific bend of mind (especially in online forums) and look for the truth instead of proof of what they believe. So if a lot of people disagree with you, there is a good chance you are wrong. btw, good chance does not mean 100%. Also, if we start trying to read the gibberish of every crackpot that comes along, no time would be spent on anything else (judging by the number of such people on the various forums I have visited). These kinds of statements remind of the Calvin and Hobbes comic: Calvin: "You know Einstein's grades were bad when he was a kid, well mine were are worse!" I have seen this happen numerous times, the crackpot says something, many people disagree, the crackpot now instead of rethinking what he said, brings up arguments like these to convince himself that he is a genius...

No really. Given that he has "college math" training, and if this question was on a test and if I was grading him, he would not get any points for this. In spirit, any "reasonable" method can be made correct. The fact that he claims a 2-2 split for 6-3 holding vs 5-4 holding has different chances, make me want to give him negative marks then and there...

I don't think this is his method. (For instance, he has refered to a page which has only % of the suit split.) What you are doing is using Bayes theorem (in a way) on top on what BebopKid is doing which was not even considered by him.

Since I have over 20 hours of college math, I didn't use the non-math method. What university, who was the professor and what grade did you get? Did the math include probability theory? Sorry, this statement of yours is quite annoying. You don't have to answer the questions above, but making statements like these to try and support your argument only shows that you don't have a convincing logical argument which is pertinent to the discussion at hand.

I am afraid jdonn is correct this time B) You have forgotten to look at the whole hand, which is 52 cards. You are considering only the "whole" suit which is just 13 cards. The percentages change based on how the other suits are distributed, which jdonn's method of calculation implicitly considers, while yours does not. Please read Stephen Tu's post for an explanation why jdonn's method works. In your simulations did you try dealing 52 cards or just 13? If 52, can you please post the code?

[hv=n=sa932&w=s&e=s&s=skj54]399|300|[/hv] i) What is the best play for 3 tricks? ii) What is the best play for 4 tricks?

Of course. *smacks head*

What if West ducks the ♦A on the first round?

4th best from AKxxx against a suit contract? :P Without a very very good reason to back it up, that is a ridiculous lead.

This is inferior to the other lines which were suggested. Each time a heart is played, LHO gets an opportunity to throw a club. You might make 6 trumps tricks, but it might be the 2 clubs tricks which become difficult to get.

We have two options for our 10th trick: either ruff a heart or, establish a club in dummy. Also, these options are likely exclusive i.e if we try to ruff a heart, we must give up on the extra club winner (as heart A will be only entry to it), if we try and set up club (say after 2 rounds of trump), defenders can knock out the entry and we go down if trumps are 3-1. The defenders can remove out option of ruffing a heart by playing two rounds of trumps or remove out option of club winner by knocking out HA before trumps are drawn. The other lines given try to cater to both options. For instance, consider the ruffing finesse. Say east covers the club K, we ruff and now duck a heart. Defenders are now stuck. If they try to knock out the entry to dummy (HA), we can now ruff a heart in dummy. If they try to prevent a heart ruff, by playing two rounds of trump, we can draw trumps, get to dummy using HA and cash our club winner in peace (without danger of being ruffed). Ducking a heart maintains the options for us and does not commit to any one line of play (ruff a heart or establish club). It forces the defenders to commit first.

I thought I would surprise Wayne, but I was surprised myself. There were already 2 non-heart votes.

Right. I guess this was too easy... on the table i managed to goof it up (only made it because of a defensive error)

What did you have in mind awm? I feel like there is some elegant solution to this hand...

Yes, X was bad, but maybe opp thought you can't play well enough. All the more reason to make it :rolleyes: