Bernoulli Mean and Variance

Compute the empirical mean and variance of binary (0/1) observations.

Implement solve(x).

Returns. Return a tuple (mean, variance) of floats, where the variance is $\widehat{p}(1-\widehat{p})\backslash hat\; p(1-\backslash hat\; p)$. Empty input, non-binary values or a non-1-D input raise ValueError.

Examples

Example 1

Input:

solve([1, 0, 1, 1])

Output:

(0.75, 0.1875)

Example 2

Input:

solve([0, 0, 0])

Output:

(0.0, 0.0)