Interesting(?) BIT-appeal

[blackshoe]

Heh.

[Trinidad]

A sim. What, exactly, are we supposed to be simulating?

Many good bridge players run simulations to check their bidding judgement, typically on hands that they have played. I am absolutely not the greatest fan of sims, since often, the underlying assumptions (double dummy play) are questionnable. But sims certainly have a function in testing your judgement after the fact.

 

If sims have a function in testing your own judgement, they can also have a function in testing someone else's judgement. So, if an expert makes a statement (e.g. "4♠ will make in 75% of the cases.") that a sim could test with a reasonable reliability, then I do not see a problem in using a sim, despite my apprehension in general.

 

Rik

[barmar]

On the other hand, if an expert (much better than the TD) says: "Given the fact that my partner has shown xyz, I will be able to take 10+ tricks about 75 % of the time, and, therefore, bidding this game at IMPs is the only LA.", a sim could help the TD. It could test whether there are indeed 10+ tricks about 75 % of the time, something the TD might not be able to envision.

I think this is just wrong.

 

The definition of an LA is in terms of what a class of players would consider and do. It doesn't matter whether their judgement is correct or not. If a significant number of those players might take an action, it's an LA, even if a simulation shows that it's a mistake.

 

We're judging humans by human standards, not an oracle.

[pescetom]

On the other hand, if an expert (much better than the TD) says: "Given the fact that my partner has shown xyz, I will be able to take 10+ tricks about 75 % of the time, and, therefore, bidding this game at IMPs is the only LA.", a sim could help the TD. It could test whether there are indeed 10+ tricks about 75 % of the time, something the TD might not be able to envision.

 

With everyone promoted to his due level of competence (hopefully not beyond) it is inevitable that players will often be better than TD, but not "much better".

Even if so, only the players polled by TD need to have the same vision as this expert, not the TD himself.

 

Not that I am against doing a sim, if sufficiently flexible and easy to use software was available to TD.

[Trinidad]

I think this is just wrong.

 

The definition of an LA is in terms of what a class of players would consider and do. It doesn't matter whether their judgement is correct or not. If a significant number of those players might take an action, it's an LA, even if a simulation shows that it's a mistake.

 

We're judging humans by human standards, not an oracle.

Let's backtrack a little.

 

I do not advocate that sims are taking over humans. Humans will rule whether an action was an LA or not.

 

The term simulation came into the discussion because jhenrikj insisted that you can only get an answer to the question what LAs there are, by simulating the position that a player is in. The problem there is that your sample size is simply too small. But if you continue on the theme of simulations and sample size, you will see quickly that computer sims do not have problems with sample size. That's how the computer sim came into the discussion.

 

In most cases, a computer sim will be utterly useless. I have said that I can envision situations where a sim may be useful to assist the TD. If a player's judgement is correct than only players with the same judgement can be considered his peers. I a player's judgement was wrong, this helps to dismiss the case.

 

Rik

[barmar]

I think it's also unrealistic to expect players to express their reasoning in percentages that could be compared with sim results.

 

Read MSC- and CtC-type columns, they generally use vague logic like "I think slam is at worst on a finesse" or "I hope partner will be able to supply a stopper". And these are some of the best players in the world.

[blackshoe]

No, no, no. They're required to express percentages, to four significant figures. B-)

[sanst]

No, no, no. They're required to express percentages, to four significant figures. B-)

:lol: :lol:

[pran]

No, no, no. They're required to express percentages, to four significant figures. B-)

Digits? (Not figures?) :lol: :D :P

[blackshoe]

Digits? (Not figures?) :lol: :D :P

figure | ˈfiɡyər |

noun

1 a number, especially one which forms part of official statistics or relates to the financial performance of a company: official census figures | a figure of 30,000 deaths annually from snakebite.

• a numerical symbol, especially any of the ten in Arabic notation: the figure 7.

• one of a specified number of digits making up a larger number, used to give a rough idea of the order of magnitude: their market price runs into five figures | [in combination] : a six-figure salary.

• an amount of money: a figure of two thousand dollars.

• (figures) arithmetical calculations: she has no head for figures.

[pran]

Oxford American Dictionary said:

 

Fair enough but (slightly) different from what my Oxford Guide to the English Language says. :P

[sanst]

Fair enough but (slightly) different from what my Oxford Guide to the English Language says. :P

America isn’t England, hasn’t been for almost 250 years. It’s a miracle that the languages don’t differ much more. Dutch Dutch and South African Dutch, better known as Afrikaans, have grown far more apart in a slightly shorter time span. I know, totally and completely OT.

[blackshoe]

"Two peoples separated by a common language…" B-)

[gordontd]

Digits? (Not figures?) :lol: :D :P

The term I was taught is “significant figures” as opposed to “decimal places”. Looking online, that still seems to be valid usage.

[pran]

The term I was taught is “significant figures” as opposed to “decimal places”. Looking online, that still seems to be valid usage.

Just for curiosity I looked up my Webster (American language) where I found some 14 entries for the noun.

Most relevant seemed to be "symbol for a number" or "amount"

[pescetom]

The term I was taught is “significant figures” as opposed to “decimal places”. Looking online, that still seems to be valid usage.

 

I too was taught that term, but the only difference I can see with respect to "decimal places" is an explicit reminder that we are rounding to a sufficient level of accuracy (so it's reasonable to express the generic frequency of an 8500 shape as 0.00% to two significant places, even knowing that it is 0.0031%).

[barmar]

The term I was taught is “significant figures” as opposed to “decimal places”. Looking online, that still seems to be valid usage.

"Decimal places" just refers to the digits after the decimal point. "Significant figures" is the total number of digits. 123.45 has 5 significant figures and 2 decimal places.

[pran]

"Decimal places" just refers to the digits after the decimal point. "Significant figures" is the total number of digits. 123.45 has 5 significant figures and 2 decimal places.

or 123.45 is a figure which has 5 significant digits and 2 decimal places. :rolleyes:

[sanst]

or 123.45 is a figure which has 5 significant digits and 2 decimal places. :rolleyes:

Since we are completely OT, I think it’s high time we discuss when to use number or figure. Please, don’t restrict yourself to natural numbers, complex, rational, real are far more interesting.

[pran]

Since we are completely OT, I think it’s high time we discuss when to use number or figure. Please, don’t restrict yourself to natural numbers, complex, rational, real are far more interesting.

Well, for what it's worth: To me number is a concrete term, figure is an abstract term. They can both be used about measurable quantities.

[gordontd]

"Decimal places" just refers to the digits after the decimal point. "Significant figures" is the total number of digits. 123.45 has 5 significant figures and 2 decimal places.

Yes. My point was that I was taught "s.f." at the same time as being taught "d.p." It sounds to me as though perhaps Pran was taught "s.d." instead of "s.f."

[RMB1]

or 123.45 is a figure which has 5 significant digits and 2 decimal places.

 

What you say may be logical but at school many of us were taught a distinction between decimal places and significant figures, and tedious exercises rounding numbers to 3d.p. (decimal places) or to 4s.f. sigificant figures.

[Trinidad]

Which gets us back on topic again:

If you use a poll of 4 people whether 1 in 6 (or 1 in 5) players would chose an action, the result will have 0 (zero) significant figures.

 

Rik

[pran]

Yes. My point was that I was taught "s.f." at the same time as being taught "d.p." It sounds to me as though perhaps Pran was taught "s.d." instead of "s.f."

Indeed.

 

A significant number to me refers to one (or more) 'significant' number(s) within a set of numbers, not to the internal properties of any particular number.

 

So if you for instance consider the population (expressed as a number) of the US states you might end up ranking the states according to their significance.

There you have an example of significant numbers.

 

Examples:

98765,43210 is a 10-digit number with 5 decimals.

98765,4321 is the same number with only 4 significant decimals (note the omission of the last zero!).

98765 is the same number with 5 significant digits.

and 99000 is again the same number with only 2 significant digits. (note the rounding of the thousands!)

[barmar]

Scientists often solve this by writing most numbers using scientific notation. 9.876543210 x 10^4 versus 9.9 x 10^4. The number of significant figures is always decimal places + 1.