An event has a probability of 0.5. How do I evaluate realtive attainment. For example how do I evaluate 10 out of 10 compared to 2 out of 2. Clearly they are both 100% but how much better is 10 out of 10? it cannot simply be 5 times better. Or 10 out of 10 to 4 out of 9 indeed any value of achievement comparison
With a probability of 0.500
2 out of 2 times occurs 1 our of every 4 times ( (1/2)2 = 1/4 )
while 10 out of 10 times occurs 1 out of every 1024 times ( (1/2)10 = 1/1024 ).
1 out of every 1024 times is 1/256th as likely to occur as 1 out of every 4 times (because 1024 / 4 = 256).
Or, 1 out of every 2 times is 256 times as likely to occur as 1 out of every 1024 times.