Essential Statistics
2nd Edition
ISBN: 9781259570643
Author: Navidi
Publisher: MCG
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Chapter 2.3, Problem 30E
a.
To determine
Find the year in which the U.S. did not participate in summer games that were held in Moscow in protest of the investigation of Afghanistan by the Soviet Union.
b.
To determine
Find the number of gold medals won by the U.S. in 1984.
c.
To determine
Check whether the number of gold medals won by the United States except 1980 and 1984 is increasing, decreasing or staying about the same.
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3. Bayesian Inference – Updating Beliefs
A medical test for a rare disease has the following characteristics:
Sensitivity (true positive rate): 99%
Specificity (true negative rate): 98%
The disease occurs in 0.5% of the population.
A patient receives a positive test result.
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a) Define the relevant events and use Bayes’ Theorem to compute the probability that the patient actually has the disease.b) Explain why the result might seem counterintuitive, despite the high sensitivity and specificity.c) Discuss how prior probabilities influence posterior beliefs in Bayesian inference.d) Suppose a second, independent test with the same accuracy is conducted and is also positive. Update the probability that the patient has the disease.
4. Linear Regression - Model Assumptions and Interpretation
A real estate analyst is studying how house prices (Y) are related to house size in square feet (X). A simple
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The analyst fits the model and obtains:
•
Ŷ50,000+150X
YBoB₁X + €
•
R² = 0.76
• Residuals show a fan-shaped pattern when plotted against fitted values.
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5. Probability Distributions – Continuous Random Variables
A factory machine produces metal rods whose lengths (in cm) follow a continuous uniform distribution on the interval [98, 102].
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Chapter 2 Solutions
Essential Statistics
Ch. 2.1 - 1. The following table lists the types of aircraft...Ch. 2.1 - Prob. 2CYUCh. 2.1 - Prob. 3CYUCh. 2.1 - Prob. 4CYUCh. 2.1 - Prob. 5ECh. 2.1 - In Exercises 5–8, fill in each blank with the...Ch. 2.1 - Prob. 7ECh. 2.1 -
In Exercises 5–8, fill in each blank with the...Ch. 2.1 - Prob. 9ECh. 2.1 - In Exercises 9–12, determine whether the statement...
Ch. 2.1 - Prob. 11ECh. 2.1 -
In Exercises 9–12, determine whether the...Ch. 2.1 - Prob. 13ECh. 2.1 - 14. The most common blood typing system divides...Ch. 2.1 - 15. Following is a pie chart that presents the...Ch. 2.1 - 16. Student expenses: The following pie chart...Ch. 2.1 - 17. Food sources: The following side-by-side bar...Ch. 2.1 -
18. Super Bowl: The following side-by-side bar...Ch. 2.1 - Prob. 19ECh. 2.1 - 20. Popular video games: The following frequency...Ch. 2.1 - Prob. 21ECh. 2.1 - Prob. 22ECh. 2.1 - Prob. 23ECh. 2.1 - Prob. 24ECh. 2.1 - Prob. 25ECh. 2.1 - 26. How secure is your job? In a survey, employed...Ch. 2.1 - Prob. 27ECh. 2.1 - Prob. 28ECh. 2.1 - Prob. 29ECh. 2.1 - 30. Bought a new car lately? The following table...Ch. 2.1 - Prob. 31ECh. 2.1 - Prob. 32ECh. 2.1 - Prob. 33ECh. 2.1 - Prob. 34ECh. 2.1 - Prob. 35ECh. 2.2 - Using the data in Table 2.7, construct a frequency...Ch. 2.2 - Prob. 2CYUCh. 2.2 - Prob. 3CYUCh. 2.2 - Prob. 4CYUCh. 2.2 - Prob. 5ECh. 2.2 -
In Exercises 5-8, fill in each blank with the...Ch. 2.2 - Prob. 7ECh. 2.2 - Prob. 8ECh. 2.2 - Prob. 9ECh. 2.2 - Prob. 10ECh. 2.2 - Prob. 11ECh. 2.2 - In Exercises 9-12, determine whether the statement...Ch. 2.2 - Prob. 13ECh. 2.2 - In Exercises 13–16, classify the histogram as...Ch. 2.2 - Prob. 15ECh. 2.2 - In Exercises 13–16, classify the histogram as...Ch. 2.2 - In Exercises 17 and 18, classify the histogram as...Ch. 2.2 - In Exercises 17 and 18, classify the histogram as...Ch. 2.2 - Prob. 19ECh. 2.2 - 20. Trained rats: Forty rats were trained to run a...Ch. 2.2 - 21. Interpret histogram: The following histogram...Ch. 2.2 - Prob. 22ECh. 2.2 - Prob. 23ECh. 2.2 - Skewed which way? For which of the following data...Ch. 2.2 - Prob. 25ECh. 2.2 - 26. Batting average: The following frequency...Ch. 2.2 - Prob. 27ECh. 2.2 - 28. Murder, she wrote: The following frequency...Ch. 2.2 - BMW prices: The following table presents the...Ch. 2.2 - Geysers: The geyser Old Faithful in Yellowstone...Ch. 2.2 - Prob. 31ECh. 2.2 - Internet radio: The following table presents the...Ch. 2.2 - Prob. 33ECh. 2.2 - Prob. 34ECh. 2.2 - Prob. 35ECh. 2.2 - Prob. 36ECh. 2.2 - 37. Silver ore: The following histogram presents...Ch. 2.2 - Classes of differing widths: Consider the...Ch. 2.3 - Weights of college students: The following table...Ch. 2.3 - Prob. 2CYUCh. 2.3 - Prob. 3ECh. 2.3 - Prob. 4ECh. 2.3 - In Exercises 3–6, fill in each blank with the...Ch. 2.3 - Prob. 6ECh. 2.3 - Prob. 7ECh. 2.3 - Prob. 8ECh. 2.3 - Prob. 9ECh. 2.3 - Prob. 10ECh. 2.3 - Prob. 11ECh. 2.3 - Prob. 12ECh. 2.3 - Prob. 13ECh. 2.3 - 14. List the data in the following stem-and-leaf...Ch. 2.3 - Prob. 15ECh. 2.3 - Prob. 16ECh. 2.3 - BMW prices: The following table presents the...Ch. 2.3 - How’s the weather? The following table presents...Ch. 2.3 - Prob. 19ECh. 2.3 - Prob. 20ECh. 2.3 - Tennis and golf: Following are the ages of the...Ch. 2.3 - Prob. 22ECh. 2.3 - Prob. 23ECh. 2.3 - 24. Safety first: Following are the numbers of...Ch. 2.3 - Prob. 25ECh. 2.3 - Prob. 26ECh. 2.3 - Prob. 27ECh. 2.3 - Prob. 28ECh. 2.3 - Prob. 29ECh. 2.3 - 30. Going for gold: The following time-series plot...Ch. 2.3 - Prob. 31ECh. 2.3 - Prob. 32ECh. 2.3 - Prob. 33ECh. 2.3 - 34. Arctic ice sheet: The following table presents...Ch. 2.3 - Prob. 35ECh. 2.4 - The population of country A is twice as large as...Ch. 2.4 - Prob. 2CYUCh. 2.4 - Prob. 3ECh. 2.4 - Prob. 4ECh. 2.4 - Prob. 5ECh. 2.4 - Prob. 6ECh. 2.4 - Prob. 7ECh. 2.4 - Prob. 8ECh. 2.4 - Prob. 9ECh. 2.4 - Prob. 10ECh. 2.4 - Prob. 11ECh. 2.4 - Prob. 12ECh. 2.4 - College degrees: Both of the following time-series...Ch. 2.4 - Food expenditures: Both of the following...Ch. 2.4 - Prob. 15ECh. 2 - Prob. 1CQCh. 2 - Prob. 2CQCh. 2 - Prob. 3CQCh. 2 - Prob. 4CQCh. 2 - Prob. 5CQCh. 2 - 6. True or false: A histogram can have more than...Ch. 2 - Prob. 7CQCh. 2 - Prob. 8CQCh. 2 - Prob. 9CQCh. 2 - Prob. 10CQCh. 2 - Prob. 11CQCh. 2 - Prob. 12CQCh. 2 - Prob. 13CQCh. 2 - Prob. 14CQCh. 2 - Prob. 15CQCh. 2 - Prob. 1RECh. 2 - Prob. 2RECh. 2 - Prob. 3RECh. 2 - Prob. 4RECh. 2 - Prob. 5RECh. 2 - Prob. 6RECh. 2 - Prob. 7RECh. 2 - Prob. 8RECh. 2 - Prob. 9RECh. 2 - Prob. 10RECh. 2 - Prob. 11RECh. 2 - Prob. 12RECh. 2 - Prob. 13RECh. 2 - Prob. 14RECh. 2 - Prob. 15RECh. 2 - Prob. 1WAICh. 2 - Prob. 2WAICh. 2 - Prob. 3WAICh. 2 - Prob. 4WAICh. 2 - Prob. 1CSCh. 2 - Prob. 2CSCh. 2 - In the chapter introduction, we presented gas...Ch. 2 - Prob. 4CSCh. 2 - Prob. 5CSCh. 2 - Prob. 6CSCh. 2 - Prob. 7CSCh. 2 - Prob. 8CSCh. 2 - Prob. 9CS
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