
Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Textbook Question
Chapter 8.2, Problem 32E
Refer to Procedure 8.1.
- a. Explain in detail the assumptions required for using the z-interval procedure.
- b. How important is the normality assumption? Explain your answer.
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Could you please answer this question using excel.Thanks
Questions
An insurance company's cumulative incurred claims for the last 5 accident years are given
in the following table:
Development Year
Accident Year 0
2018
1 2 3 4
245 267 274 289 292
2019
255 276 288 294
2020
265 283 292
2021
263 278
2022
271
It can be assumed that claims are fully run off after 4 years. The premiums received for
each year are:
Accident Year Premium
2018
306
2019
312
2020
318
2021
326
2022
330
You do not need to make any allowance for inflation.
1. (a) Calculate the reserve at the end of 2022 using the basic chain ladder method.
(b) Calculate the reserve at the end of 2022 using the Bornhuetter-Ferguson method.
2. Comment on the differences in the reserves produced by the methods in Part 1.
Calculate the correlation coefficient r, letting Row 1 represent the x-values and Row 2 the y-values. Then calculate
it again, letting Row 2 represent the x-values and Row 1 the y-values. What effect does switching the variables have
on r?
Row 1
Row 2
13
149
25
36
41
60
62
78
S
205
122
195
173
133
197
24
Calculate the correlation coefficient r, letting Row 1 represent the x-values and Row 2 the y-values.
r=0.164 (Round to three decimal places as needed.)
S
24
Chapter 8 Solutions
Introductory Statistics (10th Edition)
Ch. 8.1 - The value of a statistic used to estimate a...Ch. 8.1 - What is a confidence-interval estimate of a...Ch. 8.1 - Prob. 3ECh. 8.1 - Prob. 4ECh. 8.1 - Prob. 5ECh. 8.1 - Suppose that you lake 500 simple random samples...Ch. 8.1 - Prob. 7ECh. 8.1 - A simple random sample is taken from a population...Ch. 8.1 - Refer to Exercise 8.7 and find a point estimate...Ch. 8.1 - Prob. 10E
Ch. 8.1 - In each of Exercises 8.118.16, we provide a sample...Ch. 8.1 - Prob. 12ECh. 8.1 - In each of Exercises 8.118.16, we provide a sample...Ch. 8.1 - Prob. 14ECh. 8.1 - Prob. 15ECh. 8.1 - Prob. 16ECh. 8.1 - Wedding Costs. According to Brides Magazine,...Ch. 8.1 - Cottonmouth Litter Size. In the article The...Ch. 8.1 - Wedding Costs. Refer to Exercise 8.17. Assume that...Ch. 8.1 - Cottonmouth Litter Size. Refer to Exercise 8.18....Ch. 8.1 - Fuel Tank Capacity. Consumer Reports provides...Ch. 8.1 - Home Improvements. The American Express Retail...Ch. 8.1 - Giant Tarantulas. A tarantula has two body parts....Ch. 8.1 - Serum Cholesterol Levels. In formation on serum...Ch. 8.1 - Prob. 25ECh. 8.1 - New Mobile Homes. Refer to Examples 8.1 and 8.2....Ch. 8.2 - Find the confidence level and for a. a 90%...Ch. 8.2 - Find the confidence level and for a. an 85%...Ch. 8.2 - What is meant by saying that a 1 confidence...Ch. 8.2 - Prob. 30ECh. 8.2 - Prob. 31ECh. 8.2 - Refer to Procedure 8.1. a. Explain in detail the...Ch. 8.2 - Prob. 33ECh. 8.2 - Prob. 34ECh. 8.2 - Prob. 35ECh. 8.2 - In each of Exercises 8.348.39, assume that the...Ch. 8.2 - In each of Exercises 8.348.39, assume that the...Ch. 8.2 - In each of Exercises 8.348.39, assume that the...Ch. 8.2 - In each of Exercises 8.348.39, assume that the...Ch. 8.2 - Prob. 40ECh. 8.2 - Prob. 41ECh. 8.2 - Suppose that you will be taking a random sample...Ch. 8.2 - Prob. 43ECh. 8.2 - Prob. 44ECh. 8.2 - In each of Exercises 8.458.48, explain the effect...Ch. 8.2 - Prob. 46ECh. 8.2 - In each of Exercises 8.458.48, explain the effect...Ch. 8.2 - In each of Exercises 8.458.48, explain the effect...Ch. 8.2 - Prob. 49ECh. 8.2 - A confidence interval for a population mean has a...Ch. 8.2 - A confidence interval for a population mean has...Ch. 8.2 - Prob. 52ECh. 8.2 - Prob. 53ECh. 8.2 - In each of Exercises 8.538.60, answer true or...Ch. 8.2 - Prob. 55ECh. 8.2 - In each of Exercises 8.538.60, answer true or...Ch. 8.2 - Prob. 57ECh. 8.2 - In each of Exercises 8.538.60, answer true or...Ch. 8.2 - In each of Exercises 8.538.60, answer true or...Ch. 8.2 - In each of Exercises 8.538.60, answer true or...Ch. 8.2 - Formula 8.2 on page 344 provides a method for...Ch. 8.2 - Prob. 62ECh. 8.2 - Prob. 63ECh. 8.2 - In each of Exercises 8.638.68, we provide a sample...Ch. 8.2 - Prob. 65ECh. 8.2 - In each of Exercises 8.638.68, we provide a sample...Ch. 8.2 - In each of Exercises 8.638.68, we provide a sample...Ch. 8.2 - In each of Exercises 8.638.68, we provide a sample...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Preliminary data analyses indicate that you can...Ch. 8.2 - Prob. 75ECh. 8.2 - Prob. 76ECh. 8.2 - Medical Marijuana. An issue with legalization of...Ch. 8.2 - Prob. 78ECh. 8.2 - Medical Marijuana. Refer to Exercise 8.77. a....Ch. 8.2 - American Alligators. Refer to Exercise 8.78. a....Ch. 8.2 - Medical Marijuana. Refer to Exercise 8.77. a. The...Ch. 8.2 - Prob. 82ECh. 8.2 - Prob. 83ECh. 8.2 - Prob. 84ECh. 8.2 - Pulmonary Hypertension. In the paper Persistent...Ch. 8.2 - Fuel Expenditures. In estimating the mean monthly...Ch. 8.2 - Prob. 87ECh. 8.2 - Prob. 88ECh. 8.2 - Political Prisoners. In Exercise 8.73, you found a...Ch. 8.2 - Keep on Rolling. In Exercise 8.74, you found a 99%...Ch. 8.2 - Prob. 91ECh. 8.2 - Prob. 92ECh. 8.2 - Doing Time. The U.S. Department of Justice, Office...Ch. 8.2 - Doing Time. The U.S. Department of Justice, Office...Ch. 8.2 - Prob. 95ECh. 8.2 - Prob. 96ECh. 8.2 - Prob. 97ECh. 8.2 - Corporate Farms. The U.S. Census Bureau estimates...Ch. 8.2 - Body Temperature. A study by researchers at the...Ch. 8.2 - Prob. 100ECh. 8.2 - Clocking the Cheetah. The cheetah (Acinonyx...Ch. 8.2 - Prob. 103ECh. 8.2 - Prob. 104ECh. 8.2 - Prob. 105ECh. 8.2 - Prob. 106ECh. 8.2 - Toxic Mushrooms? Refer to Exercise 8.71. a....Ch. 8.3 - Why do you need to consider the studentized...Ch. 8.3 - Prob. 109ECh. 8.3 - Prob. 110ECh. 8.3 - Prob. 111ECh. 8.3 - Batting Averages. An issue of Scientific American...Ch. 8.3 - Prob. 113ECh. 8.3 - Two t-curves have degrees of freedom 12 and 20,...Ch. 8.3 - For a t-curve with df = 6, use Table IV to find...Ch. 8.3 - For a t-curve with df = 17, use Table IV to find...Ch. 8.3 - Prob. 117ECh. 8.3 - Prob. 118ECh. 8.3 - Fuel Tank Capacity. Consumer Reports provides...Ch. 8.3 - Prob. 120ECh. 8.3 - Prob. 121ECh. 8.3 - Prob. 122ECh. 8.3 - In each of Exercises 8.1238.128, we provide a...Ch. 8.3 - In each of Exercises 8.1238.128, we provide a...Ch. 8.3 - In each of Exercises 8.1238.128, we provide a...Ch. 8.3 - Prob. 126ECh. 8.3 - Prob. 127ECh. 8.3 - In each of Exercises 8.1238.128, we provide a...Ch. 8.3 - Preliminary data analyses indicate that you can...Ch. 8.3 - Preliminary data analyses indicate that you can...Ch. 8.3 - Sleep. In 1908, W. S. Gosset published the article...Ch. 8.3 - Preliminary data analyses indicate that you can...Ch. 8.3 - Preliminary data analyses indicate that you can...Ch. 8.3 - Preliminary data analyses indicate that you can...Ch. 8.3 - In each of Exercises 8.135-8.138, use the...Ch. 8.3 - Prob. 136ECh. 8.3 - In each of Exercises 8.1358.138, use the...Ch. 8.3 - Prob. 138ECh. 8.3 - The Coruros Burrow. The subterranean coruro...Ch. 8.3 - Forearm Length. In 1903. K Pearson and A. Lee...Ch. 8.3 - Blood Cholesterol and Heart Disease. Numerous...Ch. 8.3 - Bicycle Commuting Times. A city planner working on...Ch. 8.3 - Prob. 143ECh. 8.3 - Prob. 144ECh. 8.3 - Prob. 146ECh. 8.3 - Another type of confidence interval is called a...Ch. 8.3 - Another type of confidence interval is called a...Ch. 8.3 - Prob. 149ECh. 8.3 - Christmas Spending. In a national poll of 1039...Ch. 8 - Explain the difference between a point estimate of...Ch. 8 - Answer true or false to the following statement,...Ch. 8 - Must the variable under consideration be normally...Ch. 8 - Prob. 4RPCh. 8 - Prob. 5RPCh. 8 - Suppose that you intend to find a 95% confidence...Ch. 8 - A confidence interval for a population mean has a...Ch. 8 - Suppose that you plan to apply the one-mean...Ch. 8 - A variable of a population has a mean of 266 and a...Ch. 8 - Baby Weight. The paper Are Babies Normal? by T....Ch. 8 - The following figure shows the standard normal...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - In each of Problems 1217, we have provided a...Ch. 8 - For a t-curve with df = 18, obtain the t-value and...Ch. 8 - Millionaires. Dr. Thomas Stanley of Georgia Slate...Ch. 8 - Millionaires. From Problem 19, we know that a 95%...Ch. 8 - Prison Sentences. Researchers M. Dhami et al....Ch. 8 - Prison Sentences. Refer to Problem 21. a. Find the...Ch. 8 - Children of Diabetic Mothers. The paper...Ch. 8 - Diamond Pricing. In a Singapore edition of...Ch. 8 - Wildfires. Wildfires are uncontrolled fires that...Ch. 8 - Fuel Economy. The U.S. Department of Energy...Ch. 8 - Prob. 28RPCh. 8 - UWEC UNDERGRADUATES Recall from Chapter 1 (see...Ch. 8 - BANK ROBBERIES: A STATISTICAL ANALYSIS At the...
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