Consider a random sample $Y_1, Y_2, \dots, Y_n$ from a continuous population with mean $E(Y_i) = \mu$ and finite variance $V(Y_i) = \sigma^2$. Show that the estimator $\frac{1}{n}\sum_{i=1}^n (Y_i - \overline{Y})^2$ is a biased estimator for $\sigma^2$.
Added by Paula G.
Close
Your feedback will help us improve your experience
Sri K and 59 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Let X1,...,Xn be independent random variables with E[Xi] = 9bc and var(Xi) = σ^2, i = 1,... , n. Consider the sample sum of squares given by Sxx = Σ(Xi - X̄)^2, i=1 to n. (a) Show that E[XiXi] = σ^2 + 9bc^2 if i = j, otherwise 0. (b) Hence, show that E[XiXj] = 9bc^2 for i ≠ j. (c) Show that E[Sxx] = (n-1)σ^2. (d) Hence, show that the sample variance S^2 is unbiased for σ^2.
Sri K.
'Let U. V. and W be independent random variables with equal variances 02_ Define X U + W and Y =V-W. Find the covariance between X and Y'
Ameer S.
Suppose {X1, X2, ..., Xn} depicts a set of sample random variables drawn from a population for which E(Xi) = μ and V(Xi) = σ^2. Let T is an estimator, T = Σ (xi / n+1). Find the amount of bias in this estimator.
Dominador T.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD