Problem 5.4 on page 179 (a)--(g) (Assume the value of the parameter $p$ is 50% for the calculation in part (e)
In a random sample 765 adults in the United States, 322 say they could not cover a $400 unexpected expense without borrowing money or going into debt.
(a) What population is under consideration in the data set?
(b) What parameter is being estimated?
(c) What is the point estimate for the parameter?
(d) What is the name of the statistic that we can use to measure the uncertainty of the point estimate?
(e) Compute the value from part (d) for this context.
(f) A cable news pundit thinks the value is actually 50%. Should she be surprised by the data?
(g) Suppose the true population value was found to be 40%. If we use this proportion to recompute the value in part (e) using p = 0:4 instead of ^p, does the resulting value change much?
Problem 5.4 on page 179 (a)--(g) (Assume the value of the parameter $p$ is 50% for...
Unexpected expense. In a random sample 765 adults in the United States, 322 say they could not cover a $400 unexpected expense without borrowing money or going into debt. (a) What population is under consideration in the data set? (b) What parameter is being estimated? (c) What is the point estimate for the parameter? (d) What is the name of the statistic can we use to measure the uncertainty of the point estimate? (e) Compute the value from part (d)...
5.3 Quality control. As part of a quality control process for computer chips, an engineer at a factory randomly samples 212 chips during a week of production to test the current rate of chips with severe defects. She finds that 27 of the chips are defective. (a) What population is under consideration in the data set? (b) What parameter is being estimated? (c) What is the point estimate for the parameter? (d) What is the name of the statistic can...
Model II: Table of Parameter Estimates Parameter Estimates Standard Error P-value 12.324 0.0001 3.858 0.0119 0.5550 65.095 31 β2 0.026 0.027 0.017 Model II: ANOVA Table SourceDf SS MS F Value P-value Model (4) 7) (10) (1 0.0162 Error (5) (8) 13.65 Total (6) (9) iv. In a city that has a population of 100,000 people, what is the expected change amount in expenditure (Y) with $1,000 increase in the average annual family income (X2)? Provide an estimate based on...
Use
either the P-value method or the traditional method of testing
hypotheses. Company A uses a new production method to manufacture
aircraft altimeters. A simple random sample of new altimeters
resulted in errors listed below. Use a 0.05 level of significance
to test the claim that the new production method has errors with a
standard deviation greater than 32.2 ft which was the standard
deviation for the old production method. If it appears that the
standard deviation is greater does...
(a)-(d)?
Problem(11) (10 points) Let Z~Normal(0, 1). Recall the definition of -value, i.e., P(Z>)-r. (a) (1 point) Find the probability of P(-2a/2<Z < 2a/2) (b) (3 points) Let X1, X2, , Xa be a random sample from some known) mean p and (known) variance o2. Based on the Central Limit Theorm and part (a) above, show that the confidence intervals for the population mean u can be estimated by population with (un- P(x- <pAX+Za/2 =1-a. Za/2 (c) (2 points) The...
In this problem, assume that the distribution of differences is
approximately normal. Note: For degrees of freedom
d.f. not in the Student's t table, use
the closest d.f. that is smaller. In
some situations, this choice of d.f. may increase
the P-value by a small amount and therefore produce a
slightly more "conservative" answer.
A survey of houses and traditional hogans was made in a number of
different regions of the modern Navajo Indian Reservation. The
following table is the...
Wild irises are beautiful flowers found throughout the United States, Canada, and northern Europe. This problem concerns the length of the sepal (leaf-like part covering the flower) of different species of wild iris. Data are based on information taken from an article by R. A. Fisher in Annals of Eugenics (Vol. 7, part 2, pp. 179 -188). Measurements of sepal length in centimeters from random samples of Iris setosa (I), Iris versicolor (II), and Iris virginica (III) are as follows...
ters, Statistical Intervals for a Single Sample Prok cm : An engineer is analying the compressive strength of concrete. Compressive strength is normally distributed with σ2 1000(psi)2. A random sample of 12 specimens has Workshop: Point Estimation of Paramet or',, a mean compressive strength of x 3250 psi. (a) Construct a 95% two-sided confidence interval on mean compressive strength (b) Construct a 99% two-sided confidence interval on mean conpressive strength. Compare the width of this confidence interval with the width...
For each problem, select the correct response. (a) What is the P-value of a test of the null hypothesis? A. The probability the null hypothesis is false B. The probability, assuming the null hypothesis is false, that the test statistic will take a value at least as extreme as that actually observed C. The probability the null hypothesis is true D. The probability, assuming the null hypothesis is true, that the test statistic will take a value at least as...
In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of freedom d.f. not in the Student's t table, use the closest of that is smaller In some situations, this choice of d.l. may increase the P-value by a small amount and therefore produce a slightly more "conservative answer A survey of houses and traditional hogans was made in a number of different regions of the modern Navajo Indian Reservation. The following table is the...