[gombo121]

 hrothgar, on 2013-September-06, 09:06, said:

There are simple enough counter arguments.

Let's assume that I want to use the following convention

If I hold 3-3 in the minors, I open 1C 50% of the time and 1D 50% of the time.

I sum the total value of my spades (counting 2 for a deuce, 3 for a "three" 11 for a Jack, and so on
If the total is even, I open 1C
if the the total is odd, I open 1D

Prior to the start of the tournament, I disclose my partnership agreement to the opponents.
(In this case, I disclose the probability density function)

Furthermore, I register the mechanism by which I generate entropy to the tournament director.

At the close of the event, anyone who cares can validate that the behavior (the set of bids made) match the disclosed agreement.

In this case you are simply failing full disclosure. Your decision is related and is traceable to essential part of the deal and it may be possible for your partner to figure out the key information, eg., he happen to hold all odd spades (of course, if you're explaining the algorithm to opps, its OK, but it is not a mixed strategy any more).
To be truly (pseudo)random the entropy source have to be unrelated to the deal and I believe that human is incapable of producing one without any external aids, so systemic mixed strategies are doomed.

On the other hand, "may be light in the third seat" essentially is a mixed strategy and nobody seems to be complaining.

[hrothgar]

 gombo121, on 2013-September-08, 05:52, said:

In this case you are simply failing full disclosure. Your decision is related and is traceable to essential part of the deal and it may be possible for your partner to figure out the key information, eg., he happen to hold all odd spades (of course, if you're explaining the algorithm to opps, its OK, but it is not a mixed strategy any more).
To be truly (pseudo)random the entropy source have to be unrelated to the deal and I believe that human is incapable of producing one without any external aids, so systemic mixed strategies are doomed.

There is no reason why the key needs to be disclosed to partner.

As a practical example, lets assume that we use the count the number of odd spades held by partner key suggested by Gnasher.

Partner to know whether I choose to open 1C if I hold an odd number of spades or an even number.
(For that matter, there's 101 different possible ways to generate this same 50-50 coin flip)

The big concern is that partner and i adopt mechanisms that produce the same PDF

[awm]

I wonder how this interacts with Zia's claim that he doesn't know how Michael Rosenberg decides which minor to open with 4-4. If Michael were to choose randomly (or based on the number of odd spades), would it really matter at this point? If such a high-level and experienced partnership can claim to have "no agreement" about this, it would suggest that a random choice is perfectly legal (and perhaps need not even be disclosed, if the partnership hasn't discussed it in depth).

[aguahombre]

Zia doesn't know how MR decides, and I agree that this choice by MR whatever the key is legal. But the mere fact that with a balanced 4-4m he is not consistent in choosing one or the other is certainly disclosable when asked.

[nige1]

On BLML, a long time ago, I asked about the legality of pseudo-random pseudo-psyches e.g.

• With four deuces, you "psych" 1♣ if you feel like it.
• With four treys, 1♦
• .. And so on, holding any other specified set of cards that you can remember.

Psychs would be infrequent. A benefit would be that partner would be suspicious of your bid, only when lacking all the cards in the appropriate specified set. Hence it would be a kind of controlled-psych. Of course, you would be cheating unless you disclosed this to opponents, so that they could use similar clues. Anyway, such an agreement might flout some anti-encryption rule variants.

[barmar]

 nige1, on 2013-September-09, 07:17, said:

On BLML, a long time ago, I asked about the legality of pseudo-random pseudo-psyches e.g.

• With four deuces, you "psych" 1♣ if you feel like it.
• With four treys, 1♦
• .. And so on, holding any other specified set of cards that you can remember.

Psychs would be infrequent. A benefit would be that partner would be suspicious of your bid, only when lacking all the cards in the appropriate specified set. Hence it would be a kind of controlled-psych. Of course, you would be cheating unless you disclosed this to opponents, so that they could use similar clues. Anyway, such an agreement might flout some anti-encryption rule variants.

It's not encrypted, because that means the key is only available to partner. But both opponents can also see that they're lacking all the cards of the appropriate set, so they have just as much information as partner.

[mycroft]

A "tactical bid" is a psych (that worked) made by an expert against who he considers a less-expert pair.
A "psych" is a tactical bid (that worked) made against that same expert, by who he considers a less-expert pair.

A systemic agreement to open random minor when intending to rebid NT is disclosable, but I don't think meets either of the above definitions, provided it is in fact disclosed. If partner starts knowing that the "random" is "weaker about 80%", that's also disclosable, and time to change the frequency :-).

[dburn]

 nige1, on 2013-September-09, 07:17, said:

On BLML, a long time ago, I asked about the legality of pseudo-random pseudo-psyches e.g.

• With four deuces, you "psych" 1♣ if you feel like it.
• With four treys, 1♦
• .. And so on, holding any other specified set of cards that you can remember.

Psychs would be infrequent. A benefit would be that partner would be suspicious of your bid, only when lacking all the cards in the appropriate specified set. Hence it would be a kind of controlled-psych. Of course, you would be cheating unless you disclosed this to opponents, so that they could use similar clues. Anyway, such an agreement might flout some anti-encryption rule variants.

Would respectfully suggest that psyching 3♥ when holding four aces is unlikely to be a successful strategy in the long (or even the relatively short) run.

[nige1]

 dburn, on 2013-September-10, 20:04, said:

Would respectfully suggest that psyching 3♥ when holding four aces is unlikely to be a successful strategy in the long (or even the relatively short) run.

Reminds me of an effective "psychic" misbid with four aces: Playing her first hand In Morocco, my partner didn't realize that a "1" is an "A". She passed as dealer to earn a clear top when all other pairs were defeated in games.

The set of cards that allow a particular psych need not be four of a kind. For example, after 1♥ (Double), you might agree that a 1♠ pseudo-psych is permitted only when you hold ♥ 2 3 4.

That illustrates why this method may fall foul of some encryption laws: Partner is likely to have more ♥ than either opponent, so may be better placed to determine whether you have your bid.

[wanoff]

You're all welcome to borrow my random number generator which we use to decide how to show our weak 2 over a strong club.
Add the lowest pip in each suit held and if the sum is even bid 'x'. If sum is odd bid 'x-1'.