Problem 2. Consider the linear regression set-up Y = XB+ e where €~ Nn (0,02 In); the design matrix is n by 2 (for simplicity), and the first column of X is a column of 1s. Let Bo, 3₁ denote the Least Squares (LS) estimates of the two parameters Bo, 0₁. (i) Show that the sum of LS residuals always equals 0. (ii) Using the data, identify a 95% confidence region for the point (Bo, B₁)' on the 2-dimensional plane, i.e., find a data-dependent region CC R2 such that Prob{(Bo, B₁)' = C} = 0.95. [Hint: C will be an ellipse.] (iii) Find a sufficient condition on the design matrix X that ensures that Bo, B₁ are independent. (iv) Assume o² is known and equal to one; also assume that Bo, 3₁ are independent. Find simultaneous (joint) confidence intervals for Bo, B₁ that have simultaneous exact coverage equal to 95%.

Calculus For The Life Sciences
2nd Edition
ISBN:9780321964038
Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Publisher:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Chapter1: Functions
Section1.EA: Extended Application Using Extrapolation To Predict Life Expectancy
Problem 5EA
icon
Related questions
Question
Problem 2. Consider the linear regression set-up Y = X3 + € where e~ Nn(0, 0² In); the design matrix is n by
2 (for simplicity), and the first column of X is a column of 1s. Let Bo, B₁ denote the Least Squares (LS) estimates
of the two parameters Bo, B1.
(i) Show that the sum of LS residuals always equals 0.
(ii) Using the data, identify a 95% confidence region for the point (Bo, B1)' on the 2-dimensional plane, i.e., find
a data-dependent region CC R² such that Prob{(Bo, ß₁)' € C'} = 0.95. [Hint: C will be an ellipse.]
(iii) Find a sufficient condition on the design matrix X that ensures that Bo, ß₁ are independent.
(iv) Assume ² is known and equal to one; also assume that Bo, 3₁ are independent. Find simultaneous (joint)
confidence intervals for ßo, ß₁ that have simultaneous exact coverage equal to 95%.
Transcribed Image Text:Problem 2. Consider the linear regression set-up Y = X3 + € where e~ Nn(0, 0² In); the design matrix is n by 2 (for simplicity), and the first column of X is a column of 1s. Let Bo, B₁ denote the Least Squares (LS) estimates of the two parameters Bo, B1. (i) Show that the sum of LS residuals always equals 0. (ii) Using the data, identify a 95% confidence region for the point (Bo, B1)' on the 2-dimensional plane, i.e., find a data-dependent region CC R² such that Prob{(Bo, ß₁)' € C'} = 0.95. [Hint: C will be an ellipse.] (iii) Find a sufficient condition on the design matrix X that ensures that Bo, ß₁ are independent. (iv) Assume ² is known and equal to one; also assume that Bo, 3₁ are independent. Find simultaneous (joint) confidence intervals for ßo, ß₁ that have simultaneous exact coverage equal to 95%.
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Calculus For The Life Sciences
Calculus For The Life Sciences
Calculus
ISBN:
9780321964038
Author:
GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Publisher:
Pearson Addison Wesley,
Linear Algebra: A Modern Introduction
Linear Algebra: A Modern Introduction
Algebra
ISBN:
9781285463247
Author:
David Poole
Publisher:
Cengage Learning
College Algebra
College Algebra
Algebra
ISBN:
9781305115545
Author:
James Stewart, Lothar Redlin, Saleem Watson
Publisher:
Cengage Learning
Algebra & Trigonometry with Analytic Geometry
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage
Algebra and Trigonometry (MindTap Course List)
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:
9781305071742
Author:
James Stewart, Lothar Redlin, Saleem Watson
Publisher:
Cengage Learning
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781305652224
Author:
Charles P. McKeague, Mark D. Turner
Publisher:
Cengage Learning