/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q81 SE The accompanying data on respons... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 9: Q81 SE (page 406)

The accompanying data on response time appeared in the article "'The Extinguishment of Fires Using Low-Flow Water Hose Streams-Part II" (Fire Technology, 1991: 291-320).

Good visibility

.43 1.17 .37 .47 .68 .58 .50 2.75

Poor visibility

1.47 .80 1.58 1.53 4.33 4.23 3.25 3.22

The authors analyzed the data with the pooled t test. Does the use of this test appear justified? (Hint: Check for normality.

The z percentiles for n=8 are -1.53, -.89, -.49, -.15 , .15, .49, .89, and 1.53.)

Short Answer

Expert verified

Any test which requires normality should not be used.

Step by step solution

01

To analyzing the   t test appear justified

It appears that the good visibility does not come from a normally distributed population-based on the normal probability plot given below. For the pooled t test assumption of normality for both populations is needed. However, only the poor visibility satisfies that. Thus,

any test which requires normality should not be used

02

Step 2:To analyzing the   t test appear justified

03

To analyzing the  t test appear justified

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

The article "Quantitative MRI and Electrophysiology of Preoperative Carpal Tunnel Syndrome in a Female Population" (Ergonomics, 1997: 642-649) reported that (-473.13,1691.9) was a large-sample 95 % confidence interval for the difference between true average thenar muscle volume \(\left( {m{m^3}} \right.)\) for sufferers of carpal tunnel syndrome and true average volume for nonsufferers. Calculate and interpret a 90 % confidence interval for this difference.

Scientists and engineers frequently wish to compare two different techniques for measuring or determining the value of a variable. In such situations, interest centers on testing whether the mean difference in measurements is zero. The article "Evaluation of the Deuterium Dilution Technique Against the Test Weighing Procedure for the Determination of Breast Milk Intake" (Amer: J. of Clinical Nutr., \(1983: 996 - 1003\)) reports the accompanying data on amount of milk ingested by each of\(14\)randomly selected infants.

\(\begin{array}{*{20}{l}}{\;\;\;\;\;\;\;\;\;\;\;\;\;\;Infant\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;}\\{\;\;\;\;\;\;\;\;\;\;\;\;\;\;1\;\;\;\;\;\;\;\;\;\;\;\;2\;\;\;\;\;\;\;\;\;\;\;\;3\;\;\;\;\;\;\;\;\;\;\;\;4\;\;\;\;\;\;\;\;\;\;\;\;5}\\{D method\;\;\;\;\;\;\;\;\;\;\;1509\;\;\;\;\;1418\;\;\;\;\;1561\;\;\;\;\;1556\;\;\;\;\;2169}\\{W method\;\;\;\;\;\;\;\;\;\;1498\;\;\;\;\;1254\;\;\;\;\;1336\;\;\;\;\;1565\;\;\;\;\;2000}\\{jifference\;\;\;\;\;\;\;\;\;\;\;\;11\;\;\;\;\;\;\;\;\;\;164\;\;\;\;\;\;\;225\;\;\;\;\;\;\; - 9\;\;\;\;\;\;\;\;\;\;169}\end{array}\)

\(\begin{array}{*{20}{c}}{}&{Infant}&{}&{}&{}&{}\\{}&6&7&8&9&{10}\\{DD method}&{1760}&{1098}&{1198}&{1479}&{1281}\\{TW method}&{1318}&{1410}&{1129}&{1342}&{1124}\\{Difference}&{442}&{ - 312}&{69}&{137}&{157}\end{array}\)

\(\begin{array}{*{20}{c}}{}&{Infant}&{}&{}&{}\\{}&{11}&{12}&{13}&{14}\\{DD method}&{1414}&{1954}&{2174}&{2058}\\{TW method}&{1468}&{1604}&{1722}&{1518}\\{Difference}&{ - 54}&{350}&{452}&{540}\end{array}\)

a. Is it plausible that the population distribution of differences is normal?

b. Does it appear that the true average difference between intake values measured by the two methods is something other than zero? Determine the\(P\)-value of the test, and use it to reach a conclusion at significance level . \(05\).

The article "The Influence of Corrosion Inhibitor and Surface Abrasion on the Failure of Aluminum-Wired Twist-On Connections" (IEEE Trans. on Components, Hybrids, and Manuf. Tech., 1984: 20-25) reported data on potential drop measurements for one sample of connectors wired with alloy aluminum and another sample wired with EC aluminum. Does the accompanying SAS output suggest that the true average potential drop for alloy connections (type 1) is higher than that wfor EC connections (as stated in the article)? Carry out the appropriate test using a significance level of .01. In reaching your conclusion, what type of error might you have committed?

(Note: SAS reports the\(P\)-value for a two-tailed test.)

\(\begin{array}{*{20}{c}}{ Type }&{}&N&{ Mean }&{ Std Dev }&{ Std Error }\\1&{20}&{17.49900000}&{0.55012821}&{0.12301241}&{}\\2&{20}&{16.90000000}&{0.48998389}&{0.10956373}&{}\\{}&{ Variances }&T&{ DF }&{Prob > |T|}&{}\\{ Unequal }&{3.6362}&{37.5}&{0.0008}&{}&{}\\{}&{ Equal }&{3.6362}&{38.0}&{0.0008}&{}\end{array}\)

Determine the number of degrees of freedom for the two-sample t test or CI in each of the following.

\(\begin{array}{l}a. m = 10, n = 10, {s_1} = 5.0, {s_2} = 6.0\\b. m = 10, n = 15,{s_1} = 5.0, {s_2} = 6.0\\c. m = 10, n = 15, {s_1} = 2.0, {s_2} = 6.0\\d. m = 12, n = 24, {s_1} = 5.0, {s_2} = 6.0\\\\\end{array}\)

Olestra is a fat substitute approved by the FDA for use in snack foods. Because there have been anecdotal reports of gastrointestinal problems associated with olestra consumption, a randomized, double-blind, placebo-controlled experiment was carried out to compare olestra potato chips to regular potato chips with respect to GI symptoms ("Gastrointestinal Symptoms Following Consumption of Olestra or Regular Triglyceride Potato Chips," J. of the Amer. Med. Assoc., 1998: 150-152). Among 529 individuals in the TG control group, 17.6 % experienced an adverse GI event, whereas among the 563 individuals in the olestra treatment group, 15.8 % experienced such an event.

a. Carry out a test of hypotheses at the 5 % significance level to decide whether the incidence rate of GI problems for those who consume olestra chips according to the experimental regimen differs from the incidence rate for the TG control treatment.

b. If the true percentages for the two treatments were 15 % and 20 %, respectively, what sample sizes

\((m = n\)) would be necessary to detect such a difference with probability 90?

See all solutions

Recommended explanations on Math Textbooks

Logic and Functions

Read Explanation

Decision Maths

Read Explanation

Applied Mathematics

Read Explanation

Statistics

Read Explanation

Discrete Mathematics

Read Explanation

Geometry

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.