example: Let X = number of heads observed when a fair coin is flipped 4 times.
S = {HHHH, HHHT, HHTH, HHTT, HTHH, HTHT, HTTH, HTTT,
THHH, THHT, THTH, THTT, TTHH, TTHT, TTTH, TTTT}
The probability distribution for X:
X |
0 |
1 |
2 |
3 |
4 |
P(X=x) |
1/16 |
4/16 |
6/16 |
4/16 |
1/16 |