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Stats 2
Stats 3
S1 Topic 3: Probability
The coin and die experiment backmore
The coin die experiment consists of first tossing a coin, and then rolling a red die if the coin lands head or a green die if the coin lands tails. The coin score I (1 for heads and 0 for tails) and the die score X are recorded on each update. The probability distribution that governs the red die and the distribution that governs the green die can be chosen separately from list boxes. The following distributions are available for each die:
  • fair: each face has probability 1/6
  • 1-6 flat: faces 1 and 6 have probability 1/4 each; faces 2, 3, 4, and 5 have probability 1/8 each.
  • 2-5 flat: faces 2 and 5 have probability 1/4 each; faces 1, 3, 4, and 6 have probability 1/8 each.
  • 3-4 flat: faces 3 and 4 have probability 1/4 each; faces 1, 2, 5, and 6 have probability 1/8 each.
  • skewed left: face i has probability i / 21 for i = 1, 2, 3, 4, 5, 6.
  • skewed right: face i has probability (7 - i) / 21 for i = 1, 2, 3, 4, 5, 6.
The probability of heads p for the coin can be varied with a scroll bar. The density and moments of X are shown in blue in the graph and are recorded in the second table. On each update, the empirical density and moments of X are shown in red in the graph and are recorded in the second table.


Summary
a Java applet An applet freely available from The Probability/Statistics Object Library