Suppose that $Y_{1}, Y_{2}, \ldots, Y_{n}$ denote a random sample of size $n$ from a normal distribution with mean
$\mu$ and variance $1 .$ Consider the first observation $Y_{1}$ as an estimator for $\mu$
a. Show that $Y_{1}$ is an unbiased estimator for $\mu$.
b. Find $P\left(\left|Y_{1}-\mu\right| \leq 1\right)$
c. Look at the basic definition of consistency given in Definition 9.2. Based on the result of part
(b), is $Y_{1}$ a consistent estimator for $\mu$ ?