If Monty has freedom of choice, that is if Monty were to expose a goat BEFORE you made your first choice, then you would be left with a 50-50 pick between the remaining goat and the cash.
But the game is conducted such that Monty can only expose a goat AFTER you have made your initial choice.
Because Monty can only expose a goat AFTER you make your choice then there is a chance that Monty's freedom of choice is removed because Monty cannot choose the door you have already chosen and if you have chosen a goat Monty has no freedom of choice.
Monty's knowledge of where the goats are, coupled with your initial choice sometimes constraining Monty's choice is what changes the odds.
Legend: D1 = Door 1 D2 = Door 2 D3 = Door 3 G1 = Possible game configuration 1 G2 = Possible game configuration 2 G3 = Possible game configuration 3 G = Goat $ = 1 million dollars
List all game/choice possibilities and count the odds. D1 D2 D3 G1: G G $ G2: G $ G G3: $ G G
You choose D1 G1: G X X Monty MUST open D2 to expose a goat - if you change you WIN G2: G X X Monty MUST open D3 to expose a goat - if you change you WIN G3: $ X X Monty can open D2 or D3 to expose a goat - if you change you LOSE
You choose D2 G1: X G X Monty MUST open D1 to expose a goat - if you change you WIN G2: X $ X Monty can open D1 or D3 to expose a goat - if you change you LOSE G3: X G X Monty MUST open D3 to expose a goat - if you change you WIN
You choose D3 G1: X X $ Monty can open D1 or D2 to expose a goat - if you change you LOSE G2: X X G Monty MUST open D1 to expose a goat - if you change you WIN G3: X X G Monty MUST open D2 to expose a goat - if you change you WIN
So it's fairly easy to see that changing will cause you to win more often than not. Actually you will win 66% of the time if you change.
Only for GM cars at the moment but due to support Ford and Chrysler in the future. Eval version here: http://www.starrperformance.com.au/efilivev 5 Of course you'll need to buy an interface to connect to your vehicle.
In case anyone is interested... Here's an example of the OBD-II SAE-J1850 VPW protocol as used by GM, wrapped by another protocol of the hardware interface being used.
This is from a PC based software scan tool called EFILive V5.
The VIN is fake but can anyone tell me where the vehicle was made and by who?
The Mail is correct.
If Monty has freedom of choice, that is if Monty were to expose a goat BEFORE you made your first choice, then you would be left with a 50-50 pick between the remaining goat and the cash.
But the game is conducted such that Monty can only expose a goat AFTER you have made your initial choice.
Because Monty can only expose a goat AFTER you make your choice then there is a chance that Monty's freedom of choice is removed because Monty cannot choose the door you have already chosen and if you have chosen a goat Monty has no freedom of choice.
Monty's knowledge of where the goats are, coupled with your initial choice sometimes constraining Monty's choice is what changes the odds.
Legend:
D1 = Door 1
D2 = Door 2
D3 = Door 3
G1 = Possible game configuration 1
G2 = Possible game configuration 2
G3 = Possible game configuration 3
G = Goat
$ = 1 million dollars
List all game/choice possibilities and count the odds.
D1 D2 D3
G1: G G $
G2: G $ G
G3: $ G G
You choose D1
G1: G X X Monty MUST open D2 to expose a goat - if you change you WIN
G2: G X X Monty MUST open D3 to expose a goat - if you change you WIN
G3: $ X X Monty can open D2 or D3 to expose a goat - if you change you LOSE
You choose D2
G1: X G X Monty MUST open D1 to expose a goat - if you change you WIN
G2: X $ X Monty can open D1 or D3 to expose a goat - if you change you LOSE
G3: X G X Monty MUST open D3 to expose a goat - if you change you WIN
You choose D3
G1: X X $ Monty can open D1 or D2 to expose a goat - if you change you LOSE
G2: X X G Monty MUST open D1 to expose a goat - if you change you WIN
G3: X X G Monty MUST open D2 to expose a goat - if you change you WIN
So it's fairly easy to see that changing will cause you to win more often than not.
Actually you will win 66% of the time if you change.
Only for GM cars at the moment but due to support Ford and Chrysler in the future.v 5
Eval version here:
http://www.starrperformance.com.au/efilive
Of course you'll need to buy an interface to connect to your vehicle.
In case anyone is interested...
0 0,$00,$550 0,$560 0,$00,$4B0 0,$420 0,$00,$670 0,$D20 0,$00,$340 0,$FB0 0,$00,$315 4,$CC0 0,$00,$324 C,$120 0,$00,$333 5,$AA0 0,$00,$4C0 0,$77
Here's an example of the OBD-II SAE-J1850 VPW protocol as used by GM, wrapped by another protocol of the hardware interface being used.
This is from a PC based software scan tool called EFILive V5.
The VIN is fake but can anyone tell me where the vehicle was made and by who?
22:27:12.226: Scanning for T16 - Multiplex Engineering's #T16 interface on Com1
22:27:12.226: Connected to Com1 using baud=19200 parity=N data=8 stop=1
22:27:12.326: Send: $1F,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$
22:27:12.346: Recv: $40,$80,$42,$02,$7F,$55,$05,$5A,$5F,$00,$00,$00,$
22:27:12.346: Interface: T16 V66.127
22:27:12.346: Auto detecting OBD-II protocol: SAE J1850VPW (GM)...
22:27:12.346: Probing OBDII link...
22:27:12.356: Send: $1F,$82,$05,$68,$6A,$F1,$01,$00,$00,$00,$00,$00,$
22:27:12.397: Recv: $40,$82,$48,$6B,$10,$41,$00,$BF,$BF,$F9,$90,$B5,$
22:27:12.397: OBD-II protocol: SAE J1850VPW (GM) detected.
22:27:12.397: Request OBD compliance.
22:27:12.467: Send: $1F,$82,$05,$68,$6A,$F1,$01,$1C,$00,$00,$00,$00,$
22:27:12.507: Recv: $40,$82,$48,$6B,$10,$41,$1C,$01,$2F,$00,$00,$00,$
22:27:12.507: OBD compliance: OBD-II (California ARB)
22:27:12.507: Request GM PCM#.
22:27:12.567: Send: $1F,$82,$05,$6C,$10,$F1,$3C,$04,$00,$00,$00,$00,$
22:27:12.607: Recv: $40,$82,$6C,$F1,$10,$7C,$04,$00,$F7,$81,$C2,$52,$
22:27:12.607: PCM#: 16220610
22:27:12.607: Request GM VIN.
22:27:12.667: Send: $1F,$82,$05,$6C,$10,$F1,$3C,$01,$00,$00,$00,$00,$
22:27:12.707: Recv: $40,$82,$6C,$F1,$10,$7C,$01,$00,$36,$48,$38,$56,$
22:27:12.767: Send: $1F,$82,$05,$6C,$10,$F1,$3C,$02,$00,$00,$00,$00,$
22:27:12.807: Recv: $40,$82,$6C,$F1,$10,$7C,$02,$4B,$36,$39,$46,$59,$
22:27:12.867: Send: $1F,$82,$05,$6C,$10,$F1,$3C,$03,$00,$00,$00,$00,$
22:27:12.907: Recv: $40,$82,$6C,$F1,$10,$7C,$03,$35,$38,$31,$33,$36,$
22:27:12.907: Vin: 6H8VTK69FYL581365
22:27:13.859: Request Diagnostic Trouble Codes.
22:27:13.869: Send: $1F,$82,$05,$68,$6A,$F1,$01,$01,$00,$00,$00,$00,$
22:27:13.899: Recv: $40,$82,$48,$6B,$10,$41,$01,$00,$07,$60,$00,$89,$
22:27:13.899: No diagnostic trouble codes detected.