Statistical Misconceptions

310 Pages·2008·4.419 MB·English

by  Schuyler W. Huck

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Schuyler W. Huck
University of Tennessee – Knoxville
New York London
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Psychology Press Psychology Press
Taylor & Francis Group Taylor & Francis Group
270 Madison Avenue 27 Church Road
New York, NY 10016 Hove, East Sussex BN3 2FA
© 2009 by Taylor & Francis Group, LLC
Printed in the United States of America on acid-free paper
10 9 8 7 6 5 4 3 2 1
International Standard Book Number-13: 978-0-8058-5904-1 (Softcover) 978-0-8058-5902-7 (Hardcover)
Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, trans-
mitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter
invented, including photocopying, microfilming, and recording, or in any information storage or retrieval
system, without written permission from the publishers.
Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are
used only for identification and explanation without intent to infringe.
Library of Congress Cataloging-in-Publication Data
Huck, Schuyler W.
Statistical misconceptions / Schuyler W. Huck.
p. cm.
ISBN 978-0-8058-5902-7 (hardback) -- ISBN 978-0-8058-5904-1 (pbk.)
1. Psychometrics. I. Title.
BF39.H83 2008
150.72’7--dc22 2008019136
Visit the Taylor & Francis Web site at
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and the Psychology Press Web site at
http://www.psypress.com
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DEDICATION
This book is dedicated to three groups of individuals: those who
have overcome one or more of their statistical misconceptions,
those who will (at some point in the future) follow in the footsteps
of those in the first group, and those whose life’s work includes
helping others to cast aside false beliefs about statistics.
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BRIEF CONTENTS
Descriptive Statistics 1
Distributional Shape 19
Bivariate Correlation 39
Reliability and Validity 65
Probability 89
Sampling 121
Estimation 145
Hypothesis Testing 165
9 -Tests Involving One or Two Means 195
t
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viii Brief Contents

10 ANOVA and ANCOVA 209
P ractical Significance, Power, and
Effect Size 225
Regression 243
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CONTENTS

Preface
xiii
Descriptive Statistics
1
1.1 Measures of Central Tendency 3
1.2 The Mean of Means 9
1.3 The Mode’s Location 13
1.4 The Standard Deviation 15
Recommended Reading 18
Distributional Shape
19
2.1 The Shape of the Normal Curve 21
2.2 Skewed Distributions and Measures of
Central Tendency 25
2.3 Standard Scores and Normality 29
2.4 Rectangular Distributions and Kurtosis 33
Recommended Reading 37
Bivariate Correlation
39
3.1 Correlation Coeffi cients 41
3.2 Correlation and Causality 45
3.3 T he Effect of a Single Outlier on Pearson’s r 49
3.4 Relationship Strength and r 55
3.5 The Meaning of r = 0 59
Recommended Reading 63
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