In my Jan 15 post , Micheal Jankowski wrote,
From a gambling perspective, “5:1″ seems incorrect as “odds.†A racehorse with 5-1 odds in a 2-horse race would be the overwhelming longshot of the two. 1-5 seems more appropriate if the odds favor Zeke in 46 of 55 runs.
My response was,
Michael– Thanks. I don’t gamble, so I could easily screw the order up! Can other gamblers chime in and verify that Michael is right. Then, I’ll edit!
To my surprise, on January 16, Mark Liberman of Language Log posted “The odds of X are large”: likely or unlikely?, explaining why people often become confused when discussions involve phrases using the term “odd”. Dr. Liberman provides examples of usage in gambling, then transitioning to mathematics, he observes:
In fact, for those who think of odds in a mathematical sense, those examples are all backwards. Instead, large odds of X should mean that X is likely, as in these examples:
If I understand correct, my use of “odds” was in the mathematical sense. Michael’s is in the gambling sense. The post discussed mathematical analysis to estimate odds of winning a bet. So, did I err? Or not? I don’t know.
Or maybe there is no inconsistency between use of odds in gambling and math. My favorite comment– which may or may not reconcile the seemingly contradictory usages in math and statistics is the following:
Gary M said, January 17, 2011 @ 3:47 am
Many math texts distinguish between the “odds” of you winning, say 1:99 for an event with 0.01 probability, and the “house odds” of the house winning, which are the reverse, or 99:1. House odds are what you hear quoted by betting establishments. Since this is where most people learn the concept of “odds”, house odds are what they think of first, not their own odds.
In popular language, both are simply called “odds” so it’s no wonder there’s confusion. Large house odds mean an event is very unlikely (“the odds are long”), while large odds mean an event is very likely.
As I can think of nothing more to say on the topic of odds, I’ll close by saying I think the odds Mark Liberman regularly reads my blog are slim.
Maybe you can clear up a good deal of the confusion by inserting the phrase “The House is giving you” before any statement of gambling odds.
If “The House is giving you 5:1 odds” then you have got to be worried that yours is a long shot!
oliver– I’ve long known that I find usage of “odds” confusing. When Michael brought up the usage issue I admitted it. I found it interesting to read a professor of linguistics show that it’s not just me!
If I understand correctly, when I did the computation based on assuming the models were “right”, I found Zeke’s odds of winning are 5:1. That is he’s more likely to win than lose. There is no house in the Zeke/Bastardi bet.
Lucia, you get a leg up by defining what you mean by odds. If odds are part of the standard lingo for betting and horse racing then, of course, you have to learn what that means. Since you do run a betting emporium here you should bone up on the lingo.
I know little about betting and odds myself as I find observing the bettors at a race track more fascinating then betting. If “forced” to bet it will be the favorite to show.
http://ezinearticles.com/?Horse-Racing-Betting-Odds&id=125666
As I recall at most race tracks you cannot bet odds lower than 2/5 which would be for an odds-on favorite. I once witnessed a bettor go berserk in the track infield after placing a large bet on an odds-on favorite pacer who broke stride shortly after starting.
This is a better link for showing horse racing odds. It also shows odds as low as 1/5. Like I said, I do not know much about betting – but then I do not run a betting emporium.
http://horseracing.about.com/cs/handicapping/a/aaoddschart.htm
Usually betting odds are expressed as “odds for” or “odds against”.
My experience as a gambler in Australia is similar to ad’s comment, the odds are expressed as 5 to 1 against for the less likely event or 5 to1 on for the more likely event. As most gambling odds in horseracing etc are “against” this is regularly dropped off the description. so a 5 to 1 bet is recognized by punters as 5 to 1 against. Only when the bet is odds on is it necessary to spell it out in full , as in 5 to 1 on.
When the odds are written in newpapers & form guides 5/1 is “against” and 1/5 is “on”
Odds which are unlikely are said to be long and odds which are more likely are short. Strangely perhaps things which are very likely are “long odds on”.
Like most punters I have no idea how odds should be expressed in a mathematical sense.
Re: Kevin Johnstone (Jan 19 00:58),
As I remember 5:1 odds means that if you bet a dollar, you get 5 dollars back. So if it’s a fair bet then the probability of you winning is 0.20. Of course it’s never a fair bet. A bookmaker either offers different odds if you’re betting for or against or charges a fee. I believe it’s called vigorish
Hi DeWitt
The way the old bookies boards used to work here was if they showed 5/1 the return on a bet of $1 was $6. So the return was in line with the offered price. Whether these were fair odds was of course up to the punter. Modern computerised bookmakers boards now show the return for $1 invested so 5/1 would show 6.00 on the board. The Tote has aleays displayed the odds this way.
Probably a better way to display it, but I now hear often hear people incorrectly call those odds as 6/1.
The old boards also used to have the odds against in black and odds on in red. “in the red” was/is the term for short priced favorites. Call me old and grumpy but to me a computer screen showing 1.20 just doesn’t have the charm and excitement lof the old red 1/5 for a red hot fave.
The vig of course was and is in the percentage of the book.
A bookie in a strong competitive ring would normally have a book of 110%-120%. Provincial & country rings would often have books over $150%. Punter beware I suppose.
If you want to explore odds ratios – the likelihood of binary events across categories – start here: http://en.wikipedia.org/wiki/Odds_ratio
I, too, find the concepts don’t quite stick and always have to relearn the terminology and assumptions.
This is essentially a question of grammar, and like all questions of grammar, it boils down to prescription vs description. Prescriptivists will go back and forth as to what the “correct” convention is. Descriptivists will point out that as long as it is clear from the context which side of the bet you consider to be a long-odds proposition, either convention effectively communicates your meaning, which means both are equally correct.
Robert–
In some sense, it is always true that if two speakers manage to communicate their ideas, then something about how they are expressing themselves must be correct.
But I don’t think you’ve described the descriptivist position correctly. My impression is the descriptivist position is not that you can do whatever you want provided it’s clear in context. I think it’s more like this: The pure descriptivist describe how words, phrases and grammar usually and used and determine their meaning and usage from observing how they are used. According to this notion, if you wish what you write to be understood, you are advised to use words to use words, phrases and grammar they way they are used.
In the pure prescriptivist operates on the theory that a rule book exists, and that correct meaning and usage can be determined by finding the rule in the rule book.
In any case, prescriptivism doesn’t solve the problem that a phrase might be ambiguous. Sometimes if you look up a word, it has multiple meanings and the only way to understand its meaning when used is by understanding the context.
My impression is that in this day and age, any decent linguist will evaluate correctness from both the descriptive and prescriptive position. You’ll notice that Mark Liberman’s article examines both the dictionary definition and usage.
In my opinion, clear persuasive writing and communication should considering both views. Currently, “long odds” should be avoided because you can’t be sure how the people reading the sentence will understand the phrase. If you use it following the dictionary definition, but it turns out people don’t understand you, then you have failed to communicate clearly. Justifying your choice by showing you agree with the dictionary won’t help.
Then there’s Humpty Dumptyist:
Impenetrability! That’s what I say!
🙂
Indeed. If you’re so obscure that nobody understands you, you must be brilliant.
The movie Being There was about that sort of thing, I think.