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Question
Determine whether each of the following is a probability distribution. Give reasons for your answer.
| y | –1 | 0 | 1 |
| P(y) | 0.6 | 0.1 | 0.2 |
Solution
Here, pi > 0, `AA` i = 1, 2, 3
Now Consider,
\[\sum\limits_{i=1}^{3} \text{P}_i\] = 0.6 + 0.1 + 0.2 = 0.9 ≠ 1
∴ Given distribution is not a probability distribution.
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