Content deleted Content added
→Properties: cannot be extended |
|||
Line 38:
: and then solve the inequality for the covariance. Equality is achieved in a simple urn model: An urn contains 1 red marble and ''n'' − 1 green marbles, and these are sampled without replacement until the urn is empty. Let ''X''<sub>''i''</sub> = 1 if the red marble is drawn on the ''i''th trial and 0 otherwise.
: A finite sequence that achieves the lower covariance bound cannot be extended to a longer exchangeable sequence.
* For an infinite exchangeable sequence,
| |||