Mathematics All Around (6th Edition)
6th Edition
ISBN: 9780134434681
Author: Tom Pirnot
Publisher: PEARSON
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Textbook Question
Chapter 14.1, Problem 5E
Sharpening Your Skills.
In Exercises 5 and 6, construct a relative frequency table and a histogram for the data given.
The ages of 60 people who volunteered to help victims of the earthquake in Nepal:
21, 23, 27, 22, 23, 29, 28, 24, 24, 25, 27, 22, 26, 26, 23, 23, 26, 28, 25, 24, 28, 27, 24, 23, 29, 28, 24, 22, 27, 26, 22, 24, 26, 21, 24, 28, 24, 25, 22, 25, 27, 21, 23, 26, 23, 23, 27, 27, 23, 21, 22, 27, 26, 23, 25, 29, 24, 27, 27, 26.
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Module Code: MATH380202
3. (a) Let {} be a white noise process with variance σ2.
Define an ARMA(p,q) process {X} in terms of {+} and state (without proof)
conditions for {X} to be (i) weakly stationary and (ii) invertible.
Define what is meant by an ARIMA (p, d, q) process. Let {Y} be such an ARIMA(p, d, q)
process and show how it can also be represented as an ARMA process, giving the
AR and MA orders of this representation.
(b) The following tables show the first nine sample autocorrelations and partial auto-
correlations of X and Y₁ = VX+ for a series of n = 1095 observations. (Notice
that the notation in this part has no relationship with the notation in part (a) of
this question.)
Identify a model for this time series and obtain preliminary estimates for the pa-
rameters of your model.
X₁
= 15.51, s² = 317.43.
k
1
2
3
4
5
6
7
Pk
0.981
0.974
0.968
akk 0.981 0.327
8
9
0.927
0.963 0.957 0.951 0.943 0.935
0.121 0.104 0.000 0.014 -0.067 -0.068 -0.012
Y₁ = VX : y = 0.03, s² = 11.48.
k
1…
Let G be a graph with n ≥ 2 vertices x1, x2, . . . , xn, and let A be the adjacency matrixof G. Prove that if G is connected, then every entry in the matrix A^n−1 + A^nis positive.
Module Code: MATH380202
1. (a) Define the terms "strongly stationary" and "weakly stationary".
Let {X} be a stochastic process defined for all t € Z. Assuming that {X+} is
weakly stationary, define the autocorrelation function (acf) Pk, for lag k.
What conditions must a process {X+) satisfy for it to be white noise?
(b) Let N(0, 1) for t€ Z, with the {+} being mutually independent. Which of
the following processes {X+} are weakly stationary for t> 0? Briefly justify your
answers.
i. Xt for all > 0.
ii. Xo~N(0,) and X₁ = 2X+-1+ &t for t > 0.
(c) Provide an expression for estimating the autocovariance function for a sample
X1,..., X believed to be from a weakly stationary process. How is the autocor-
relation function Pk then estimated, and a correlogram (or acf plot) constructed?
(d) Consider the weakly stationary stochastic process ✗+ = + + +-1+ +-2 where
{E} is a white noise process with variance 1. Compute the population autocorre-
lation function Pk for all k = 0, 1, ....
Chapter 14 Solutions
Mathematics All Around (6th Edition)
Ch. 14.1 - Sharpening Your Skills. In Exercises 1 and 2,...Ch. 14.1 - Sharpening Your Skills. In Exercises 1 and 2,...Ch. 14.1 - Sharpening Your Skills. In Exercises 3 and 4,...Ch. 14.1 - Sharpening Your Skills. In Exercises 3 and 4,...Ch. 14.1 - Sharpening Your Skills. In Exercises 5 and 6,...Ch. 14.1 - Sharpening Your Skills. In Exercises 5 and 6,...Ch. 14.1 - Prob. 7ECh. 14.1 - Sharpening Your Skills. In Exercises 7 and 8,...Ch. 14.1 - Prob. 9ECh. 14.1 - Sharpening Your Skills. In Exercises 9 and 10,...
Ch. 14.1 - Prob. 11ECh. 14.1 - Prob. 12ECh. 14.1 - Applying What Youve Learned. Customers at...Ch. 14.1 - Applying What Youve Learned. Scheduling a rec...Ch. 14.1 - Applying What Youve Learned. Data similar to that...Ch. 14.1 - Applying What Youve Learned. Data similar to that...Ch. 14.1 - Comparing wage data. The following bar graphs...Ch. 14.1 - Applying What Youve Lerarned. Comparing wage data....Ch. 14.1 - Applying What Youve Learned. Comparing wage data....Ch. 14.1 - Applying What Youve Learned. Comparing wage data....Ch. 14.1 - Applying What Youve Learned. Comparing wage data....Ch. 14.1 - Prob. 22ECh. 14.1 - Prob. 23ECh. 14.1 - Prob. 24ECh. 14.1 - Prob. 25ECh. 14.1 - For Exercises 23 26, use the four graphs of the...Ch. 14.1 - Applying What Youve Learned. Comparing training...Ch. 14.1 - Applying What Youve Learned. Comparing weight-loss...Ch. 14.1 - Applying What Youve Learned. Super Bowl scores....Ch. 14.1 - Applying What Youve Learned. Law School Aptitude...Ch. 14.1 - In Exercises 31 34, first group the data using an...Ch. 14.1 - Applying What Youve Learned. In Exercises 31 34,...Ch. 14.1 - In Exercises 31 34, first group the data using an...Ch. 14.1 - Applying What Youve Learned. In Exercises 31 34,...Ch. 14.1 - Communicating Mathematics What is the difference...Ch. 14.1 - Communicating Mathematics If you are using a bar...Ch. 14.1 - Communicating Mathematics What is the difference...Ch. 14.1 - Communicating Mathematics What do you see as an...Ch. 14.1 - Challenge Yourself How might you present three...Ch. 14.1 - Challenge Yourself 42. The following table is an...Ch. 14.2 - Prob. 1ECh. 14.2 - Prob. 2ECh. 14.2 - Sharpening Your Skills Find the mean, median, and...Ch. 14.2 - Prob. 4ECh. 14.2 - Prob. 5ECh. 14.2 - Prob. 6ECh. 14.2 - Prob. 7ECh. 14.2 - Prob. 8ECh. 14.2 - Prob. 9ECh. 14.2 - Prob. 10ECh. 14.2 - Prob. 11ECh. 14.2 - Prob. 12ECh. 14.2 - Prob. 13ECh. 14.2 - Prob. 14ECh. 14.2 - Prob. 15ECh. 14.2 - Prob. 16ECh. 14.2 - In Exercises 1720, a give the five-number summary...Ch. 14.2 - Prob. 18ECh. 14.2 - In Exercises 1720, a give the five-number summary...Ch. 14.2 - In Exercises 1720, a give the five-number summary...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - In Exercises 2128, find the mean, median, and mode...Ch. 14.2 - Many colleges assign numerical points to grades as...Ch. 14.2 - Prob. 30ECh. 14.2 - Exam scores. Izzy had an 84 and an 86 on his first...Ch. 14.2 - Prob. 32ECh. 14.2 - Prob. 33ECh. 14.2 - Prob. 34ECh. 14.2 - Exam scores. Assume that in your History of Film...Ch. 14.2 - Prob. 36ECh. 14.2 - Prob. 37ECh. 14.2 - Prob. 38ECh. 14.2 - Prob. 39ECh. 14.2 - Example 6 Using Stem-and-Leaf Home Run Records...Ch. 14.2 - Prob. 41ECh. 14.2 - Prob. 42ECh. 14.2 - Prob. 43ECh. 14.2 - Prob. 44ECh. 14.2 - Prob. 45ECh. 14.2 - Prob. 46ECh. 14.2 - Prob. 47ECh. 14.2 - A college placement office has made a comparative...Ch. 14.2 - Prob. 49ECh. 14.2 - Prob. 50ECh. 14.2 - Give three separate real-life examples in which...Ch. 14.2 - Which measure of central tendency do you think is...Ch. 14.2 - Manipulating data. Choose some set of data...Ch. 14.2 - Analyzing misleading graphs. Find a graph in the...Ch. 14.2 - Prob. 55ECh. 14.2 - Prob. 56ECh. 14.2 - Prob. 57ECh. 14.2 - Prob. 58ECh. 14.2 - Prob. 59ECh. 14.2 - Prob. 60ECh. 14.2 - Prob. 61ECh. 14.2 - Prob. 62ECh. 14.2 - Prob. 63ECh. 14.2 - Prob. 64ECh. 14.2 - Prob. 65ECh. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Sharpening Your Skills Find the range, mean, and...Ch. 14.3 - Prob. 9ECh. 14.3 - Prob. 10ECh. 14.3 - Prob. 11ECh. 14.3 - Prob. 12ECh. 14.3 - Prob. 13ECh. 14.3 - Prob. 14ECh. 14.3 - Prob. 15ECh. 14.3 - Prob. 16ECh. 14.3 - Prob. 17ECh. 14.3 - Prob. 18ECh. 14.3 - Prob. 19ECh. 14.3 - Applying What Youve Learned Summarizing age data....Ch. 14.3 - Prob. 21ECh. 14.3 - Prob. 22ECh. 14.3 - Prob. 23ECh. 14.3 - Prob. 24ECh. 14.3 - Prob. 25ECh. 14.3 - Prob. 26ECh. 14.3 - Prob. 27ECh. 14.3 - Prob. 28ECh. 14.3 - Prob. 29ECh. 14.3 - Prob. 30ECh. 14.3 - In Exercises 31 and 32, we present information on...Ch. 14.3 - In Exercises 31 and 32, we present information on...Ch. 14.3 - Human resources. As the manager of the human...Ch. 14.3 - Prob. 34ECh. 14.3 - Prob. 35ECh. 14.3 - Prob. 36ECh. 14.3 - Prob. 37ECh. 14.3 - Prob. 38ECh. 14.3 - Laptop batteries. A particular brand of laptop was...Ch. 14.3 - Study times. A group of students were sampled with...Ch. 14.3 - Prob. 41ECh. 14.3 - Prob. 42ECh. 14.3 - Prob. 43ECh. 14.3 - Use the following graphs for Exercise 44 a. Which...Ch. 14.3 - Prob. 45ECh. 14.3 - Prob. 46ECh. 14.3 - Prob. 47ECh. 14.3 - Prob. 48ECh. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 1 6 has...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Assume that the distribution in Exercises 7 12...Ch. 14.4 - Use the following graph of the standard normal...Ch. 14.4 - Use the following graph of the standard normal...Ch. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 18ECh. 14.4 - Prob. 19ECh. 14.4 - Prob. 20ECh. 14.4 - Prob. 21ECh. 14.4 - Prob. 22ECh. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 24ECh. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 28ECh. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 30ECh. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 32ECh. 14.4 - Use Table 14.19 to find the percent of the area...Ch. 14.4 - Prob. 34ECh. 14.4 - Prob. 35ECh. 14.4 - In Exercises 35 - 40, we give you a mean, a...Ch. 14.4 - Prob. 37ECh. 14.4 - Prob. 38ECh. 14.4 - Prob. 39ECh. 14.4 - Prob. 40ECh. 14.4 - Prob. 41ECh. 14.4 - In Exercises 41 - 46, we give you a mean, a...Ch. 14.4 - Prob. 43ECh. 14.4 - Prob. 44ECh. 14.4 - Prob. 45ECh. 14.4 - Prob. 46ECh. 14.4 - Prob. 47ECh. 14.4 - Prob. 48ECh. 14.4 - Prob. 49ECh. 14.4 - Prob. 50ECh. 14.4 - Prob. 51ECh. 14.4 - Prob. 52ECh. 14.4 - Prob. 53ECh. 14.4 - Prob. 54ECh. 14.4 - Prob. 55ECh. 14.4 - Prob. 56ECh. 14.4 - Prob. 57ECh. 14.4 - Prob. 58ECh. 14.4 - Prob. 59ECh. 14.4 - Prob. 60ECh. 14.4 - Prob. 61ECh. 14.4 - Prob. 62ECh. 14.4 - Prob. 63ECh. 14.4 - Weight lifting.In a power lifting competition the...Ch. 14.4 - Strength of cables.A certain type of cable has a...Ch. 14.4 - Prob. 66ECh. 14.4 - Prob. 67ECh. 14.4 - Prob. 68ECh. 14.4 - Prob. 69ECh. 14.4 - Prob. 70ECh. 14.4 - Prob. 71ECh. 14.4 - Prob. 72ECh. 14.4 - Prob. 73ECh. 14.4 - Prob. 74ECh. 14.4 - Analyzing the SATs. Assume that the math SAT...Ch. 14.4 - Prob. 76ECh. 14.4 - Prob. 77ECh. 14.4 - Prob. 78ECh. 14.4 - Prob. 79ECh. 14.4 - Prob. 80ECh. 14.4 - Prob. 81ECh. 14.4 - Prob. 82ECh. 14.4 - Prob. 83ECh. 14.4 - Prob. 84ECh. 14.4 - Prob. 85ECh. 14.4 - Prob. 86ECh. 14.4 - If a distribution has a mean of 40 and a standard...Ch. 14.4 - Prob. 88ECh. 14.4 - Prob. 89ECh. 14.4 - Prob. 90ECh. 14.5 - In Exercises 1 and 2, state what kind of...Ch. 14.5 - In Exercises 1 and 2, state what kind of...Ch. 14.5 - For Exercises 3 6, do the following: a. Plot the...Ch. 14.5 - Prob. 4ECh. 14.5 - Prob. 5ECh. 14.5 - Prob. 6ECh. 14.5 - Prob. 7ECh. 14.5 - Prob. 8ECh. 14.5 - Prob. 9ECh. 14.5 - Prob. 10ECh. 14.5 - Prob. 11ECh. 14.5 - Prob. 12ECh. 14.5 - In Exercises 11 14, find the line of best fit for...Ch. 14.5 - Prob. 14ECh. 14.5 - Prob. 15ECh. 14.5 - Prob. 16ECh. 14.5 - Prob. 17ECh. 14.5 - Prob. 18ECh. 14.5 - In Exercises 19 22, find the line of best fit for...Ch. 14.5 - In Exercises 19 22, find the line of best fit for...Ch. 14.5 - In Exercises 19 22, find the line of best fit for...Ch. 14.5 - In Exercises 19 22, find the line of best fit for...Ch. 14.5 - In Example 3, we found the absolute value of the...Ch. 14.5 - Prob. 24ECh. 14.5 - Prob. 25ECh. 14.5 - Prob. 26ECh. 14.5 - Prob. 27ECh. 14.CR - Prob. 1CRCh. 14.CR - Prob. 2CRCh. 14.CR - Prob. 3CRCh. 14.CR - Prob. 4CRCh. 14.CR - The lists represent the ages of actors M and...Ch. 14.CR - Prob. 6CRCh. 14.CR - Prob. 7CRCh. 14.CR - Prob. 8CRCh. 14.CR - Prob. 9CRCh. 14.CR - Prob. 10CRCh. 14.CR - Prob. 11CRCh. 14.CR - Prob. 12CRCh. 14.CR - Prob. 13CRCh. 14.CR - Prob. 14CRCh. 14.CR - Prob. 15CRCh. 14.CR - Prob. 16CRCh. 14.CR - Prob. 17CRCh. 14.CR - State what kind of correlation, if any, is...Ch. 14.CR - Prob. 19CRCh. 14.CT - Prob. 1CTCh. 14.CT - Prob. 2CTCh. 14.CT - Prob. 3CTCh. 14.CT - Prob. 4CTCh. 14.CT - Prob. 5CTCh. 14.CT - Prob. 6CTCh. 14.CT - Prob. 7CTCh. 14.CT - Prob. 8CTCh. 14.CT - Prob. 9CTCh. 14.CT - Prob. 10CTCh. 14.CT - Prob. 11CTCh. 14.CT - Prob. 12CTCh. 14.CT - Prob. 13CTCh. 14.CT - Prob. 14CTCh. 14.CT - Prob. 15CTCh. 14.CT - Prob. 16CTCh. 14.CT - Prob. 17CTCh. 14.CT - Prob. 18CT
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