This morning when I saw my friend’s Facebook status that says, “N Srinivasan is the worst father-in-law since Dasharath #IPLFixing”, I was totally taken aback. I started analyzing Spot-fixing and did some reverse engineering.
Spo(r)t- fixing is suddenly on everybody’s mind and we all know three young cricketers are accused of doing it for no real reason other than greed. It is not just the players and bookies who are involved in spot-fixing; they need to know good Math to fix it up. Still, I’m not here to comment on these gentlemen as they already earned money illegally far in excess. They are innocent and nothing is illegal unless somebody is caught ( 😛 )
As I said there is lot of mathematics behind spot-fixing, I wanted to discuss what makes spot-fixing possible. Everybody gambles in life at some point or the other but what makes a bet possible? This is found through probabilities. We all must have heard about “Odds” on the event. To keep it simple, you think of an upcoming match (event) and you estimate assess your probability of it turning your way and then you place a bet based on that estimate. There are Jokers (bookies) who will take your bet and come up with their own estimate of what’s going to happen, which they give you is called Odds on the event.
Students who have solved “Tossing a coin and placing a dice” in probability can easily understand this. Let us assume Mr. Ravi shastri is with Captain D and Mr. Sanjay manjrekar is with Captain VK at the centre for the toss. Captain D spins the coin and Mr. VK says tails. Both of them, every one of us watching it on Television, know the probability of it landing tails is ½. When a bookie is willing to take a bet on this, he’ll give you odds as 1:1 i.e for every 10 rupees you bet, you get 10 rupees back if the coin land tails.And then you agree it’s pretty stupid bet to make as you keep betting you’ll lose your money half the time.
Real Story: Imagine placing a dice instead. The probability of getting “2″ is 1/6 and this opens up more discussions seemingly more chances for betting. A bookie will offer odds of 5:1 on “2″; that is on every 10 rupees you get 50 if the dice shows “2” and if it shows anything else then you lose your 10. And this is the chance to manifold your money, sounds exciting? Would anyone place a bet like this?
For the mathematic this is actually just a stupid bet to make as with the coin. Again, if you keep betting, you’ll lose your 50 out of every six times.On the other side, five out of every six bettors lose money whoever has placed a bet.
The reason bookies might offer such odds—1:1 for the coin, 5:1 for the dice—is that they know their probabilities as well as you do, and naturally they don’t want to lose money. So if you find a bookie offering quite different odds than you expect, it’s likely he knows something you don’t. Let’s say a bookie says to you “Ten times your money back if it comes up tails” wowhh!! You started thinking, now you make gamble of Rs. 1000 for you have estimated a chance of 50-50 and you’ll go home with Rs. 10000 if you win.
Climax: Now imagine the 6 faces of the dice are 6 balls in an over and you are an avid IPL follower from past 6 years. You know that bowler RP will bowl a no-ball about once in every six-ball over (Probability is 1/6, odds 5:1). Along comes the joker (bookie) – B who calls you and say “100 times your money back if bowler RP bowls exactly one no-ball in the over”. Wowhh, your eyes widen with lot of excitement you tweet and you wanted to fork out Rs. 10000 which you couldn’t win at the time of coin bet. So,you gamble again and put more money.On the other side thousands of funny/silly cricket fans do the same.
Now, what you, I and every one of us don’t know is that Bookie-B has already instructed bowler RP to bowl two no-balls instead of one in that over. The bowler bowls the last ball of the over a no-ball and Captain D’s team win the match. For doing so, bowler RP gets his cut from the bookie-B which he has collected from the bets. They both laugh all the way, till they do shopping for their girlfriend and finally end up in towels.