Moneybridge vs. GIB

[Free]

- Opps get a lot more HCP (which usually results in more total points and money).  I know I've done calculations in the past, and HCP NS vs HCP EW were about equal.  However, if you switch sides now and then, your opps can get way more HCP than average.

Sorry but this comment shows a complete and utter lack of understanding about probability and statistics of any kind. It is equivalent to the following argument.

 

You and I will both pick a card from each of 100 different decks and whoever picks more aces wins. However, if sometimes you pick first and sometimes I pick first then you can get way more aces than I get, which is not fair.

 

Do you know what "random" means?

Sorry but you'd be surprized of my understanding of probability. However I believe you forgot 1 important word in my sentence ("can") and my remark at the bottom of my post. I didn't say it's so in the long run (that would be foolish), and playing about 10 boards each time makes a huge difference since there's more variance. If I'd play 1000 boards I would have a better chance to reach the obvious average of 20HCP.

 

Your example is completely not equivalent. The one with the coins however is a lot more relevant.

 

I looked up my previous post where I used REAL data to show what I'm talking about:

http://forums.bridgebase.com/index.php?sho...ndpost&p=276799

You'll see that there a big difference between the average NS/EW and the average myside/oppsside in this session.

 

Obviously, if you'd keep the seats fixed, you'll have sequences of boards where 1 side gets more HCP than the other side. So it won't change much. However, for me it's frustrating that you're sitting EW for a few hands and don't get much HCP, suddenly you switch sides and the HCP also switched sides so the series of bad boards continues.

 

If you'd look at ALL the hands I've played in moneybridge (not just the ones in 1 session) I'll probably have around 20HCP each time (which is statistically correct), but the fun of one session can go away pretty quickly if your side keeps getting very few hcp. Since I play pretty short sessions, this factor is quite important for me.

[Lobowolf]

- Opps get a lot more HCP (which usually results in more total points and money).  I know I've done calculations in the past, and HCP NS vs HCP EW were about equal.  However, if you switch sides now and then, your opps can get way more HCP than average.

Sorry but this comment shows a complete and utter lack of understanding about probability and statistics of any kind. It is equivalent to the following argument.

 

You and I will both pick a card from each of 100 different decks and whoever picks more aces wins. However, if sometimes you pick first and sometimes I pick first then you can get way more aces than I get, which is not fair.

 

Do you know what "random" means?

Sorry but you'd be surprized of my understanding of probability. However I believe you forgot 1 important word in my sentence ("can") and my remark at the bottom of my post. I didn't say it's so in the long run (that would be foolish), and playing about 10 boards each time makes a huge difference since there's more variance. If I'd play 1000 boards I would have a better chance to reach the obvious average of 20HCP.

 

Your example is completely not equivalent. The one with the coins however is a lot more relevant.

 

I looked up my previous post where I used REAL data to show what I'm talking about:

http://forums.bridgebase.com/index.php?sho...ndpost&p=276799

You'll see that there a big difference between the average NS/EW and the average myside/oppsside in this session.

 

Obviously, if you'd keep the seats fixed, you'll have sequences of boards where 1 side gets more HCP than the other side. So it won't change much. However, for me it's frustrating that you're sitting EW for a few hands and don't get much HCP, suddenly you switch sides and the HCP also switched sides so the series of bad boards continues.

 

If you'd look at ALL the hands I've played in moneybridge (not just the ones in 1 session) I'll probably have around 20HCP each time (which is statistically correct), but the fun of one session can go away pretty quickly if your side keeps getting very few hcp. Since I play pretty short sessions, this factor is quite important for me.

ok, but there's no difference in your expectation, for a session of any duration, whether you're N/S every time, E/W every time, alternate every hand, or play N/S twice followed by E/W seven times, then N/S twice again.

 

Yes, the short-term swings can be quite disparate, but a priori, there's no seating sequence at all that would give you any different likelihood of getting more points, fewer points, or an average amount of points as compared with any other seating sequence.

[TimG]

- Opps get a lot more HCP (which usually results in more total points and money).  I know I've done calculations in the past, and HCP NS vs HCP EW were about equal.  However, if you switch sides now and then, your opps can get way more HCP than average.

Suppose you distribute HCP NS-EW every round as follows: 25-15, 15-25, 25-15,...  In the long run, NS and EW will have the same amount of HCP.  However, if you also switch sides every round, then your team may get 15HCP on average, while opps get 25 on average!

Are you saying that there is a difference in average HCP held depending upon whether you are always south or switch back and forth between south and west? That the seat switching changes the variance of HCP held?

 

I'm sure you will agree that the expected HCP are the same whether you stay in the same seat or switch. And, that the expected variance (in any set of X boards) is also the same regardless of position.

 

So really, the only problem with switching seats is a perception that the "cold streaks" are somehow following you. This is really the same sort of thinking as watching a flipped coin come up heads three times in a row and thinking that it must be "due" for a tails.

[Free]

Indeed. However, I've also had "hot streaks" so it cancels out. My point is that the streaks aren't as pleasant as having a tight game. Long term statistics are irrelevant for the "fun factor". :lol:

[jdonn]

Sorry but you'd be surprized of my understanding of probability.

After reading the rest of your post, I would be. Where you sit has nothing to do with your short term streaks, long term streaks, variance, average, or anything else. All it impacts is your own superstition.

 

However, for me it's frustrating that you're sitting EW for a few hands and don't get much HCP, suddenly you switch sides and the HCP also switched sides so the series of bad boards continues.

This sums up everything. That frustration is entirely illogical. You can be frustrated that you altogether had a very long streak of bad hands, but if you equate that in any way to the directions you were sitting then you are wrong.

[awm]

You seem to be implying that points come in "runs" (i.e. that there will be a bunch of hands where N/S has more points followed by a bunch of hand where E/W has more points) -- this happens sometimes but really each hand is independent from the last and it's pure random chance.

 

You could easily have a tourney where you sit N/S the whole time and get no points each hand, whereas if you had switched to E/W halfway through you'd have good hands for the second half. This is just as likely as a tourney where N/S has "the points" for the first half and E/W has "the points" for the second half.

 

I suppose there is some psychological effect (but not a real one).

 

The vulnerabilities on the other hand are an issue. If you play a tourney where you are NV for more than half the hands, your ability to score total points is substantially reduced. Of course, it does average out (mean is the same) but swapping vulnerability at random CAN increase the variance.

[Jlall]

As long as you're east you can't lose basically.

[cherdanno]

To avoid the bad streaks, you should walk once around your PC after every hand. This has the same effect as changing seats.

[mtvesuvius]

To avoid the bad streaks, you should walk once around your PC after every hand. This has the same effect as changing seats.

Mine is against a wall, what should I do?

[barmar]

I also suspect (but have no way of proving) that Barry Crane's rule may have had some statistical validity in times of manually shuffled / duplicated boards. With the advent of computer dealt truly random hands, the value of the rule is only for peace of mind.

The rule that the queen lies over the jack comes from rubber bridge. You're more likely to play the queen on the jack than the jack on the queen. Thus the queen will tend to be immediately above the jack when the cards are face up, immediately below the jack when the cards are face down, and immediately over the jack when the cards are redealt.

But why would the position of the queen be different for majors versus minors? That's what Barry Crane's rule is about.

[xcurt]

For those playing a lot of bbo moneybridge, how well does GIB play? How much better does is play if you give it more cpu (Uday or Fred?). Is it the best computer program? I tried wbridge5 since it's free and it's hopeless, I cannot believe it honestly won the computer world championship once or twice, it was so bad I'm not going to pay money to try Jack if Jack lost to it on the computer worlds.

 

I'm not interested in playing with the computer, I'm interested in writing a bridge program btw.

[cherdanno]

GIB's card play is very good. It does have some weirdnesses, e.g. it often removes guesses for you.

[hanp]

Do you know what "random" means?

Sorry but you'd be surprized of my understanding of probability.

Please surprise us!

[gnasher]

But why would the position of the queen be different for majors versus minors?  That's what Barry Crane's rule is about.

I don't know. The rule I stated has been around for ages. The Encyclopedia of Bridge credits it to a Clagett Bowie, who was born twenty years before Barry Crane.

 

Maybe Crane decided that applying this rule to computer-dealt hands wasn't sufficiently irrational, so he added an extra absurdity?

[P_Marlowe]

<snip>

I looked up my previous post where I used REAL data to show what I'm talking about:

http://forums.bridgebase.com/index.php?sho...ndpost&p=276799

You'll see that there a big difference between the average NS/EW and the average myside/oppsside in this session.

 

Obviously, if you'd keep the seats fixed, you'll have sequences of boards where 1 side gets more HCP than the other side.  So it won't change much.  However, for me it's frustrating that you're sitting EW for a few hands and don't get much HCP, suddenly you switch sides and the HCP also switched sides so the series of bad boards continues.

 

If you'd look at ALL the hands I've played in moneybridge (not just the ones in 1 session) I'll probably have around 20HCP each time (which is statistically correct), but the fun of one session can go away pretty quickly if your side keeps getting very few hcp.  Since I play pretty short sessions, this factor is quite important for me.

This is a real observation and can be proven mathematically.

 

Simply put: If you are on the loosing side, the probability that

you will stay on this side is higher and growing over time.

The probability that the score will be +-0 will go too zero, if time

goes on, if I remember it correct even with exponenatial speed.

 

But switching sides has nothing to do with it and wont change

anything at all, only a reset will.

 

With kind regards

Marlowe

[Free]

@Han: I have a master in computer science. Over the years we had at least 4 courses which included different kinds of logic and probability calculations. For these courses I had 12, 14, 15 and 16. These were actually the better scores of my entire studies. Since you can't stand me, I'm sure you won't believe this.

 

So, while I know what I'm talking about, and while is said like 10 times that I know that in the long run it cancels out, it doesn't cancel out in short games of about 10 boards.

 

Switching sides and who has more HCP is similar to flipping a coin and guessing what it is. This is also similar to flipping 2 coins at the same time and see if they match (this case I actually got in one of the courses). You have 4 possible results, 2 winning, 2 losing, so yes, you keep having 50-50 win-loss distributions. However, there are 2 factors playing, while flipping 1 coin only has 1 factor. This makes a difference in the short run.

Shooting at myself, but switching seats can even cause the reverse effect: NS having more HCP, but my side having an average of 20...

 

So again, yes, keeping fixed seats won't solve the winning and losing streaks. The point about being vulnerable and not vulnerable is another factor which cancels out in the long run. But keeping fixed seats WILL make you feel less robbed by BBO if you have a losing streak. Having a better feeling when losing is imo an improvement for BBO.

[Codo]

Frederic,

 

you have your opinion on this topic. But you are quite alone in the dark.

 

Of course we all had these sessions IRL , at BBO or with the Gibs where you are dealt one bad hand after the other. And we all dislike these hands, espacially at total point tournements or rubber.

 

But nobody besides you -at least nobody I know- thinks that this bad fealling gets worse because he had all the bad hands as south and no all the bad hands as west.

You are the only one who cares. All others hate the bad hands and do not care about rotating.

 

And a major point: I deeply belive that my partner and I should built up a bidding system for hands with 3-9 HCPS, because we "never" have more then this. When I get the statistics after the event, we somehow managed to get 10 HCPS on average, but we never feal like this at the table.

 

So our experience too has a lot to do with what you feal, but not much with reality.

[Free]

Simply put: If you are on the loosing side, the probability that

you will stay on this side is higher and growing over time.

The probability that the score will be +-0 will go too zero, if time goes on, if I remember it correct even with exponenatial speed.

Say person A lost 6 coin flips in a row against a neutral person. Person B lost 10 coin flips in a row against another neutral person. You're telling me that person B has more chance of losing again than person A? :rolleyes:

 

You probably ripped this argument completely out of it's context, for example the doubling up method (or how is it called?). It basically states that you start betting on a coin flip, and if you lose you bet the double amount and play again. So flip 1 you invest 1$, flip 2 2$, flip 3 4$,... This way, every time you win, you win all your investments + 1$. Seems great in theory since you can't lose. Your investments increase exponentially (10 losses in a row means you've invested 1023$ and need to pay 1024 to play again - by 20 you need more than 1000000$!). With unlimited amounts of cash, you'd always win. With limited amounts you see that it can go bad very quickly!

[jdonn]

So again, yes, keeping fixed seats won't solve the winning and losing streaks.

But keeping fixed seats WILL make you feel less robbed by BBO if you have a losing streak.

How don't you see that the first quote being true (I agree) makes the second quote completely illogical?

[gnasher]

Switching sides and who has more HCP is similar to flipping a coin and guessing what it is.  This is also similar to flipping 2 coins at the same time and see if they match (this case I actually got in one of the courses).  You have 4 possible results, 2 winning, 2 losing, so yes, you keep having 50-50 win-loss distributions.  However, there are 2 factors playing, while flipping 1 coin only has 1 factor.  This makes a difference in the short run.

Are you seriously trying to tell us that there's a higher variance in flipping two unbiased coins and seeing if they land the same way up than in flipping one unbiased coin and seeing if it comes up heads?

 

Going back to bridge, the question of how which seat you're sitting in is relevant only if it affects what cards you are dealt. If the same, or an equivalent, dealing algorithm is used regardless of which seat you're in, the seat can have no effect in either the long term or the short term. To say that it does makes no more sense than to say that a run of bad cards can be caused by a bird flying past the window.

 

But keeping fixed seats WILL make you feel less robbed by BBO if you have a losing streak.

I don't have a masters in anything, but even my meagre understanding of logic and probability is sufficient to make me feel equally robbed regardless of where I was sitting when I was dealt the bad hands.

[Free]

~snip~

I suppose there is some psychological effect (but not a real one).

 

The vulnerabilities on the other hand are an issue. If you play a tourney where you are NV for more than half the hands, your ability to score total points is substantially reduced. Of course, it does average out (mean is the same) but swapping vulnerability at random CAN increase the variance.

I'll summarize and then leave this topic alone again like I did last year.

 

1. Yes it's psychological, I said that before. Wheither the seats are fixed or not, my total earnings/losses won't change much. It's not about total points and the money after playing 1000 boards, it's about the FUN when playing TEN boards.

2. The variance CAN indeed increase, that's my whole point. Not only by vulnerability, but also by seating. Sitting NS is flipping a coin, being vulnerable is flipping another coin. NS having more HCP is flipping another... You can remove 2 coins from the equation by fixed seats and normal vulnerability changes.

3. The variance can even decrease by switching positions! But see nr 1.

[655321]

I am reminded of this entertaining thread that contains the following glorious quote:

 

Since I have over 20 hours of college math, I didn't use the non-math method.

[Free]

I am reminded of this entertaining thread that contains the following glorious quote:

 

Since I have over 20 hours of college math, I didn't use the non-math method.

It's not about the math...

[Little Kid]

I don't play moneybridge, but I would think that if your seating is random and therefore also the vulnerabilities you are assigned then the variance of potential scores increases (as opposed to roughly identical number of times vul/nv with fixed seats). With the extreme examples being always vul and never vul throughout a session. I don't know how the BBO software functions but if seating truly is random then there would be more variance than with fixed seats.

 

On the topic of hcps and seats, it probably depends a lot on how BBO is programmed? Say it is designed such that throughout a sessions N, S, E and W all have an average of 10 hcps. Then changing seats randomly should also increase the variance on your average hcp range in the session. If the hands are randomly dealt however it makes no difference whatsoever where you are sitting.

 

But to be honest, I wouldn't really mind the increased variance of my hands and I doubt the small difference there might be would influence my enjoyment. If i got 4333 4432 10 counts on every hand I would be quite annoyed though.

[IdiotVig]

It's not about the math...

 

Sorry, but you'd be surprized by my knowledge of non-math.