5.5 7.2 7.3 6.3 8.1 6.8 7.0 7.0 6.8 6.5 7.0 6.3 7.9 9.0 8.6 8.7 7.8 9.7 7.4 7.7 9.7 8.0 7.7 11.6 11.3 11.8 10.7 data below give accompanying strength observations for cylinders. 6.3 5.8 7.8 7.1 7.2 9.2 6.6 8.3 7.0 8.7 7.4 8.1 7.4 8.5 8.9 9.8 9.7| 14.1 12.6 11.6 r to obtaining data, denote the beam strengths by X, .., Xm and the cylinder strengths by Y,, ., Y: Suppose that the X's constitute a random sample from a di standard deviation o, and that the Y's form a random sample (independent of the X's) from another distribution with mean u, and standard deviation o,. Use rules of expected value to show that X- Y is an unbiased estimator of u, - p,. O EX - ) = (E) - E(ñ) = H1- H2 O E(X - Y) = V E(X) – E(Y) = H1 - 42 O EX - ) = E(X) - E(Y) = H1- 42 nm

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
Consider the accompanying data on flexural strength (MPa) for concrete beams of a certain type.
5.5
7.2
7.3
6.3
8.1
6.8
7.0
7.0
6.8
6.5
7.0
6.3
7.9
9.0
8.6
8.7
7.8
9.7| 7.4
7.7
9.7
8.0
7.7
11.6
11.3
11.8
10.7
The data below give accompanying strength observations for cylinders.
6.3
5.8
7.8
7.1
7.2
9.2
6.6
8.3
7.0
8.7
7.4
8.1
7.4
8.5
8.9
9.8
9.7
14.1
12.6
11.6
., Xm and the cylinder strengths by Y,, .., Yo. Suppose that the X's constitute a random sample from a distribution with mean u,
Prior to obtaining data, denote the beam strengths by X,,
and standard deviation o,
and that the Y,'s form a random sample (independent of the X's) from another distribution with mean µ, and standard deviation o,.
(a) Use rules of expected value to show that X – Y is an unbiased estimator of µ, - Hg.
EX – ) = (E(X) - EC)
= H1 - 42
O E(X – )
= V E(X) - E(Y) = H1 - H2
E(X) – E(Y)
-
O E(X – ):
= H1 - H2
nm
O E(X – Y) = nm E(X) – E(Y) = H1 - H2
O E(X – Y) = E(X) – E(Y) = µ1 - H2
Calculate the estimate (in MPa) for the given data. (Round your answer to three decimal places.)
MPа
(b) Use rules of variance to obtain an expression for the variance and standard deviation (standard error) of the estimator in part (a).
v(X - ) = v(X) + V(n
+
Identify the next step in this rule from the options below.
02
+
O vX – Y)
n1
n2
O vx - )
01
02
n1
n2
01
02
O vix - )
n1
n2
2
O viX - Y) =
01
+
n1
n2
Since standard deviation is the square root of variance, it follows that
ox - ỹ = V
V(X - Y)
01
O ox - = V
02
n1
n2
02
O ox - =
n1
n2
2
01
02
O ox - =
n1
n2
2
01
02
O ox - =
+
n1
n2
Compute the estimated standard error (in MPa). (Round your answer to three decimal places.)
MPа
(c) Calculate a point estimate of the ratio o, / 0, of the two standard deviations. (Round your answer to three decimal places.)
Transcribed Image Text:Consider the accompanying data on flexural strength (MPa) for concrete beams of a certain type. 5.5 7.2 7.3 6.3 8.1 6.8 7.0 7.0 6.8 6.5 7.0 6.3 7.9 9.0 8.6 8.7 7.8 9.7| 7.4 7.7 9.7 8.0 7.7 11.6 11.3 11.8 10.7 The data below give accompanying strength observations for cylinders. 6.3 5.8 7.8 7.1 7.2 9.2 6.6 8.3 7.0 8.7 7.4 8.1 7.4 8.5 8.9 9.8 9.7 14.1 12.6 11.6 ., Xm and the cylinder strengths by Y,, .., Yo. Suppose that the X's constitute a random sample from a distribution with mean u, Prior to obtaining data, denote the beam strengths by X,, and standard deviation o, and that the Y,'s form a random sample (independent of the X's) from another distribution with mean µ, and standard deviation o,. (a) Use rules of expected value to show that X – Y is an unbiased estimator of µ, - Hg. EX – ) = (E(X) - EC) = H1 - 42 O E(X – ) = V E(X) - E(Y) = H1 - H2 E(X) – E(Y) - O E(X – ): = H1 - H2 nm O E(X – Y) = nm E(X) – E(Y) = H1 - H2 O E(X – Y) = E(X) – E(Y) = µ1 - H2 Calculate the estimate (in MPa) for the given data. (Round your answer to three decimal places.) MPа (b) Use rules of variance to obtain an expression for the variance and standard deviation (standard error) of the estimator in part (a). v(X - ) = v(X) + V(n + Identify the next step in this rule from the options below. 02 + O vX – Y) n1 n2 O vx - ) 01 02 n1 n2 01 02 O vix - ) n1 n2 2 O viX - Y) = 01 + n1 n2 Since standard deviation is the square root of variance, it follows that ox - ỹ = V V(X - Y) 01 O ox - = V 02 n1 n2 02 O ox - = n1 n2 2 01 02 O ox - = n1 n2 2 01 02 O ox - = + n1 n2 Compute the estimated standard error (in MPa). (Round your answer to three decimal places.) MPа (c) Calculate a point estimate of the ratio o, / 0, of the two standard deviations. (Round your answer to three decimal places.)
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps with 2 images

Blurred answer
Similar questions
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman