A member of Penguin Group (USA) Inc. A member of Penguin Group (USA) Inc. ALPHA BOOKS Published by the Penguin Group Penguin Group (USA) Inc., 375 Hudson Street, New York, New York 10014, USA Penguin Group (Canada), 90 Eglinton Avenue East, Suite 700, Toronto, Ontario M4P 2Y3, Canada (a division of Pearson Penguin Canada Inc.) Penguin Books Ltd., 80 Strand, London WC2R 0RL, England Penguin Ireland, 25 St. Stephen’s Green, Dublin 2, Ireland (a division of Penguin Books Ltd.) Penguin Group (Australia), 250 Camberwell Road, Camberwell, Victoria 3124, Australia (a division of Pearson Australia Group Pty. Ltd.) Penguin Books India Pvt. Ltd., 11 Community Centre, Panchsheel Park, New Delhi—110 017, India Penguin Group (NZ), 67 Apollo Drive, Rosedale, North Shore, Auckland 1311, New Zealand (a division of Pearson New Zealand Ltd.) Penguin Books (South Africa) (Pty.) Ltd., 24 Sturdee Avenue, Rosebank, Johannesburg 2196, South Africa Penguin Books Ltd., Registered Offices: 80 Strand, London WC2R 0RL, England Copyright © 2009 by W. Michael Kelley All rights reserved. No part of this book shall be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. No patent liability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of information contained herein. For information, address Alpha Books, 800 East 96th Street, Indianapolis, IN 46240. ISBN: 1-101-15010-6 Library of Congress Catalog Card Number: 2006926601 Note: This publication contains the opinions and ideas of its author. 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Contents Introduction Chapter 1: Displaying Descriptive Statistics HjbbVg^o^c\YViV^ciVWaZh!X]Vgih!VcY\gVe]h 1 Frequency Distributions .......H..]..d.l..^.c..\..n..d.j..g..Y..V...i.V...^.c..V...i..V..W..aZ................................................ 2 Histograms ......H..].d..l..^.c.\...n.d..j..g..[..g.Z.f..j..Z..c.X..n...Y..^.h.i.g..^W..j..i..^d..c..^.c..V....X.]..V..g..i....................................... 5 Bar Charts .........................H..]..d.l...^c..\..n..d.j..g..X..V..i..Z..\.d..g.^X..V..a..Y..V..i..V...^.c..V...X..]..V..g.i............................ 8 Pie Charts ........H..].d..l..^.c.\...n.d..j..g..X..V..i.Z..\..d.g.^.X..V..a.Y...V..i.V...^.c..V...X..^.g.X..a.Z............................................. 14 Line Charts ........................H..]..d.l..^.c.\...n..d.j..g..Y..V..i..V...d.k..Z.g...i.^.b..Z...^.c..V...X..]..V..g.i............................. 19 Scatter Charts ......H..]..d.l...^c..\..g..Z.a.V..i..^d..c.h..]..^e..h..W.Z..i..l..Z..Z..c..i..l..d..k..V..g.^.V..W..aZ..h..^.c..V....X.]..V..g..i.Y..................... 21 Chapter 2: Calculating Descriptive Statistics: Measures ;o^fc YC^ce\ntir]aZl XTZendency V i 25 Mean ...............................................I..]..Z...V..k.Z..g.V..\..Z..................................................... 26 Median ...............................G..^.\..].i...h.b..V...X.`...^.c..i..].Z...b...^Y...Y..aZ............................................... 30 Midrange ........................=..V..a[..l..V..n...W.Z..i..l..Z..Z..c..i..].Z...Z..c.Y...e.d.^.c..i.h........................................... 32 Mode ...................;..^.c.Y..^.c..\..i..].Z...b...d.h.i...[.g.Z..f..j..Z..c.i..k..V..a.j..Z..................................................... 33 Percentile ...................................D..c..V...h..X.V...aZ...[..g.d.b....&..i..d..&..%.%............................................ 36 Weighted Mean ...................................6..k..Z.g..V..\.^.c..\..j..h.^.c.\...Y..^.[.[..Z..g.Z..c.i...l..Z..^\..]..i.h...................... 42 Mean of a Frequency Distribution ...............6..k..Z..g.V..\.^.c..\..Y..^.h.X..g.Z..i..Z..Y...V..i.V.............................. 45 ChapMteera 3n: oCf al cGurloautpinedg FDreqsucernipcyt iDvies tSritbautitisotnic s..:. .M..Z8.e.V.ai.as.X.uZ.j.r.agV.e.is.. ^c.co.\.f. .iV.].ia.Z].r.Z.ib.a.YZt..iV^.ho.cg.n.d. .[..\..g.d..j..e.Z..YZ..Y.Y.V.V.i.i.V...... 4571 Range ...........................................=..d.l...l..^.Y..Z...^.h..n..d.j..g..Y..V..i..V..4......................................... 52 Interquartile Range ..........;..^c..Y..^.c.\...i.]..Z...b..^.Y..Y..a.Z...*..%..e.Z..g.X..Z..c..i..d.[...i.]..Z...Y..V..i..V............................ 54 Outliers ....................................H..Z..e.V..g..V..i.^.c.\...i.]..Z...\..d.d.Y....Y..V..i.V...[..g.d..b...i.]..Z...W..V..Y..................... 58 Visualizing Distributions .....7..d..m.".V..c..Y..".l..]..^h.`..Z..g..e.a.d..i.h..V..c..Y...Y..^.h.i..g.^.W.j..i..^d..c..Y...^V..\..g.V..b...h................. 62 Stem-and-Leaf Plot ...................................I..].Z.I..b]..Zd..h.Ói..dX.l.d.b.Z.g.bd..ed.dc.l..lZ..Vg..nd.h.[.i.Y.d..Vb..iZ.V.V..h.j..g.Z...Y..^.h.e.Z..g.h.^.d.c.... 66 V Variance and Standard Deviation ofof ra G PrXopuupleiad^t iDoYna^h te.a. ....d......[...g...........Z..c.X..n....Y..................... 871 Chebyshev’s Theorem ..................E..j..i.i..^c..\..i..]..Z..h..i.V..c..Y..V..g.Y...Y..Z..k..^.V..i.^.d.c...i.d...l..d.g.`....................... 85 I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh iii i c [ d 9 g ^ 8 h Z c d [Z] h h d ^ ciZ g V b^ ^c\ eZ i ] a c\ Vj Va [ gZfj ^hig^Wji^dch Table of Contents Chapter 4: Introduction to Probability L]ViVgZi]ZX]VcXZh4 89 HiVgi^c\l^i]i]ZWVh^Xh Types of Probability .................................................................................................. 90 8dbW^c^c\egdWVW^a^i^Zhjh^c\ÆdgÇ Addition Rules for Probability .................................................................................... 98 Conditional Probability ..............E..g.d.W..V..W..^.a^.i..^Z..h..i..]..V..i..Y..Z..e.Z..c..Y...d.c...d.i..]..Z.g...Z.k..Z..c.i..h...................106 The Multiplication Rule for Probability .I..l..d..d..g..b..d..g.Z...Z.k..Z..c.i..h..d.X..X..j..g.g.^.c..\..V..i...i.]..Z...h.V..b..Z...i..^b...Z...116 6cdi]ZglVnidXVaXjaViZXdcY^i^dcVaegdWVW^a^i^Zh Bayes’ Theorem .......................................................................................................120 Chapter 5: Counting Principles and Probability Distributions DYYhndjXVcXdjcidc 123 =dlegdWVWaZ^h^ii]ViildhZeVgViZZkZcihdXXjg4 Fundamental Counting Principle ..............................................................................124 =dlbVcnlVnhXVcndjVggVc\ZVXdaaZXi^dcd[i]^c\h4 Permutations ..........................................................................................................127 L]Zci]ZdgYZgd[dW_ZXih^hcdi^bedgiVci Combinations .........................................................................................................129 EgdWVW^a^injh^c\Y^hXgZiZYViV Probability Distributions ..........................................................................................135 Chapter 6: Discrete Probability Distributions 7^cdb^Va!Ed^hhdc!VcY]neZg\ZdbZig^X 141 Jh^c\XdZ[ÒX^Zcihi]ViVgZXdbW^cgVi^dch Binomial Probability Distribution ..............................................................................142 Poisson Probability Distribution .......9..Z.i..Z..g.b..^.c..^c..\..e..g.d.W..V..W..^.a.^i..^.Z.h..d.d.ik.Z..g..h..e.Z..X..^Ò..X...^.c.i..Z.d.g.k.V..a.h........149 g e W l 6W cY h] The Poisson Distribution as an Approxim^ ationh to] the Binomial Distribution ...................156 Z a Z YZ Hypergeometric Probability Distributicon ........^g^..V...........c........Z.....V.................e..Z.......Z.c.........159 V l] G k i d a Chapter 7: Continuous Probability DistributiYons V g Éc Z 165 7ZaaXjgkZhVcYo"hXdgZh Normal Pobability Distribution .................................................................................166 W DcZ!ild!VcYi6]gZZhiVcYVgYYZk^Vi^dch[gdbiX]ZbZVc The Empirical Rule ...................................c.........................................d.....................179 d i ]Zg W egdWV gi Using the Normal Distribution to Approximate the Binomial Distribution .......................182 <d^c\[gdbVWZaa"h]VeZYidVWdm"h]VeZYY^hig^Wji^dc Continuous Uniform Distribution .............................................................................186 Exponential Distribution ..........A.^.`..Z..i..]..Z..E..d.^.h.h.d..c..Y...^h.i..g.^.W..j..i.^.d.c..!.W..j..i..X..d..c.i..^c..j..d.j..h....................189 Chapter 8: Sampling and Sampling Distributions Ldg`^c\l^i]VhjWhZid[VedejaVi^dc 195 HdbVcnlVnhid\Vi]ZgVhVbeaZ Probability Sampling ........................................................................a.......................196 S Fainmitpel iPnogp uDliastrioibnu Ctiornr eocft itohne MFaVHecgZatboYnr ..c.\...Y.E.g.Z..Y..g^.X^.W.i.j^.ci.\.^.d.ci.].d[.Z...W.Z.Z.[.].V...k.^.d.g.l.^id.Z.i].[.g.h..V.V.bh.Y.be.a.dZ.V..b.k.Z..eV.d.c..h......d......210957 E ^\ ZWZ]V^kd c gV h Sampling Distribution of the Proportion .....................................................................207 EgZY^Xi^c\egdedgi^dch[gdbVhbVaaedejaVi^dc Finite Population Correction Factor for the Sampling Distribution of the Proportion ..........215 iv d Xj i i g c c W Z 9 V ]V a h V W i ni ^ h] i ^c a a Xie ^ d ^ a W i i i i ^ i V a c^ bV^ a Z b ^ ^ i ^Z Z kZcih g c ^c \ db Z c jbW h Zg ^cdb^Va j ^hi c b ZV ^ c i] ] Y ^hXgZ b V e g d ja Z I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh Table of Contents Chapter 9: Confidence Intervals Ejii^c\hVbeaZhidldg` 219 =dljcgZegZhZciVi^kZXdjaYVhVbeaZWZ4 Introduction to Confidence Intervals for the Mean .......................................................220 8ZcigVaa^b^ii]ZdgZbidi]ZgZhXjZ Confidence Intervals for the Mean with Large Samples and Sigma Known ......................221 A^[Zl^i]djii]ZXZcigVaa^b^ii]ZdgZb Confidence Intervals for the Mean with Small Samples and Sigma Known ......................225 >cigdYjX^c\i]ZHijYZciÉhi"Y^hig^Wji^dc Confidence Intervals for the Mean with Small Samples and Sigma Unknown ..................229 LZaXdbZWVX`!XZcigVaa^b^ii]ZdgZb Confidence Intervals for the Mean with Large Samples and Sigma Unknown ..................235 Confidence Intervals for the Proportion .....:..h.i..^.b..V..i.^.c..\..e..Z.g..X.Z..c..i.V..\..Z..h..[.g.d..b...V...e..d.e.j..a.V..i.^.d..c.......239 I^bZidgZ_ZXihdbZcjaa]nedi]ZhZh Chapter 10: Hypothesis Testing for a Single Population 243 Introduction to Hypothesis Testing for the Mean L..]..V..i.V.V..g.Za..c..j..aa..V..c].Y...V..a.i.Z..g.c.V..i..^Zk..Z..]..n.e.d..i.]..Z.h..Z.h.4...244 8Vaa^c\dc i XZci ^ V Hypothesis Testing for the Mean with n v I 3]Z0n acnZdZ SYigma WKZngcown Y..h....hZ.g^i..........i........\..........247 Hypothesis Testing for the Mean with n < 30 and Sigma Known^ ...................j..^..............255 7g^c\^c\W Vi ]Z d W Hypothesis Testing for the Mean with n < 30 and Sigma Unknown l...............................259 A^`Zi]Za V ZXi ^c ] Hypothesis Testing for the Mean with n > 30 and Sigma Unknown ...............................265 IZhi^c\eZgXZciV\Zh^chiZVYd[bZVch Hypothesis Testing for the Proportion .........................................................................271 Chapter 11: Hypothesis Testing for Two Population8s ddbeVg^c\b=inledie]dZejh^aoV^ci\^dcbZVch 279 i ^ Hypothesis Testing for Two Means with n > 30 and SigmYa Known .......Y.........................280 L]ZcedejVa i Hypothesis Testing for Two Means with n < 30 and Sigma Known ......................j..iZ........286 Cdh^\bV hbVaahVbeaZh2i"Y^hig^Wji^dc Hypothesis Testing for Two Means with n < 30 and Sigma Unknown ............................289 Oh^chiZVYd[Ih Hypothesis Testing for Two Means with n v 30 and Sigma Unknown ............................299 L]Vi]VeeZchl]Zci]ZildhVbeaZhVgZgZaViZY4 Hypothesis Testing for Two Means with Dependent Samples ..........................................302 8dbeVg^c\edejaVi^dceZgXZciV\Zh Hypothesis Testing for Two Proportions ......................................................................309 Chapter 12: Chi-Square and Variance Tests IZhi^c\XViZ\dg^XVaYViV[dgkVg^Vi^dc 317 >hi]ZYViVY^hig^WjiZYi]ZlVnndji]dj\]i^ildjaYWZ4 Chi-Square Goodness-of-Fit Test .................................................................................318 Chi-Square Test for Independence ................6..g.Z...i..].Z...k..V..g.^.V..W..aZ..h..g..Z.a.V..i..Z.Y...4........................331 IZhi^c\kVg^Vi^dc^chiZVYd[i]ZbZVc Hypothesis Test for a Single Population Variance .........................................................338 >cigdYjX^c\i]Z;"Y^hig^Wji^dc Hypothesis Test for Two Population Variances .............................................................346 Chapter 13: Analysis of Variance 8dbeVg^c\bjai^eaZbZVchl^i]i]Z;"Y^hig^Wji^dc 351 I]ZbdhiWVh^X6CDK6egdXZYjgZ One-Way ANOVA: Completely Randomized Design ......................................................352 6YY^c\VWadX`^c\kVg^VWaZidi]ZiZhi One-Way ANOVA: Randomized Block Design .............................................................371 I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh v ^ a i V b b i a a i W j Y i ! d ^ c W Z g W i g ^ ^ n h ] Z g d Zg b X V^c id d g ^jW idc X `i " ZY i c h ih d o X "h d h gZ Z ^ d Z Vaa n c c Y WZ Table of Contents h dc d ^ h e Vg ;^cY^c\gZaVi ^ ^ Chapter 14: Correlation and Simple Regression Analysis k 389 9ZhXg^W^c\i]ZhigZc\i]VcYY^gZXi^dcd[VgZaVi^dch]^e Correlation ............................................................................................................390 A^cZd[WZhiÒi Simple Regression Analysis .......................................................................................396 IZhihi]ViYdcdigZfj^gZVhhjbei^dchVWdjii]ZedejaVi^dch Chapter 15: Nonparametric Tests 413 IZhii]ZbZY^Vcd[VhVbeaZ The Sign Test with a Small Sample Size ......................................................................414 IZhibZY^Vchjh^c\o"hXdgZh The Sign Test with a Large Sampcle Size ......................................................................418 i ^ e 6eeani]Zh^\ciZhiidildYZeZcYZciYViVhZih T The Paired-Sample Sign T]esZt8 d(InbWf#^ 25) ...j.^..id...Y.^.[....c.[.Y..............Z..hW..Z.d..i........g.........b.....hi............4213 [ Z cZX l Z il The Wilcoxon Rank Sum Test for Small Samples .........................................................425 JhZo"hXdgZhidbZVhjgZgVc`Y^[[ZgZcXZh The Wilcoxon Rank Sum Test for Large Samples .........................................................428 9^[[ZgZcXZ^cbV\c^ijYZWZilZZcYZeZcYZcihVbeaZh The Wilcoxon Signed-Rank Test ................................................................................431 8dbeVg^c\bdgZi]VcildedejaVi^dch The Kruskal-Wallis Test ................8.d..g.g.Z..aV..i..^c..\..Y..V..i.V...h.Z..i.h..V..X..X..d.g.Y..^.c.\..i..d..g.V..c.`...Y..^[..[.Z..g.Z..c.X..Z.h.......436 The Spearman Rank Correlation Coefficient Test .........................................................442 Chapter 16: Forecasting EgZY^Xi^c\[jijgZkVajZhd[gVcYdbkVg^VWaZh 449 I]ZbdhiWVh^X[dgZXVhi^c\iZX]c^fjZ Simple Moving Average ...........................................................................................450 GZXZciYViV^hlZ^\]iZYbdgZ]ZVk^an Weighted Moving Average ........................................................................................454 6hZa["XdggZXi^c\[dgZXVhi^c\iZX]c^fjZ Exponential Smoothing ............................................................................................458 6YYigZcYhidi]ZhZa["XdggZXi^c\bZi]dY Exponential Smoothing with Trend Adjustment ...........................................................462 6XXdjci[dgigZcYhVcYhZVhdcVa^cÓjZcXZh Trend Projection and Seasonality ..............................................................................468 I]Z^cYZeZcYZcikVg^VWaZYdZhcÉi]VkZidWZi^bZ Causal Forecasting ..................................................................................................477 Z Vhj g Chapter 17: Statistical Process Cmontrol J^ h^c\hciVinie^hZi^XhidbZVhjgZZfjVa^Zin 483 e ^c i] i h d[ bZci Introduction to Statistical Process Control ...................................................................484 BZVcVcYgVc\ZXdcigdaX]Vgih Statistical Process Control for Variable Measurement ....................................................484 8VaXjaViZi]Zegdedgi^dcd[YZ[ZXi^kZ^iZbh Statistical Process Control for Attribute Measurement Using p-charts ..............................491 8djci^c\i]ZcjbWZgd[YZ[ZXi^kZ^iZbh Statistical Process Control for Attribute Measurement Using c-charts ..............................495 >hVegdXZhhXVeVWaZd[eZg[dgb^c\VXXdgY^c\idYZh^\c4 Process Capability Ratio ...........................................................................................498 BZVhjg^c\XVeVW^a^in[dgVegdXZhhi]Vi]Vhh]^[iZY Process Capability Index ..........................................................................................500 vi ZZ l c i l i V i e i i h V Z Z h Z Y g : Z [ [ Y i V Z hV Y V ] V Z Wa h ]Zh^ o g Y c c " d h V \ gZ X i Zc Z a b h Z \ d adg Z f jVa^inb \ I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh Table of Contents Chapter 18: Contextualizing Statistical Concepts ;^\jg^c\djil]ZcidjhZl]Vi[dgbjaV 503 GZ[ZgZcXZIVWaZh *(& 6eeZcY^m6/8g^i^XVaKVajZhVcY8dcÒYZcXZ>ciZgkVah *)& 6eeZcY^m7/=nedi]Zh^hIZhi^c\ *)' 6eeZcY^m8/GZ\gZhh^dcVcY6CDK6:fjVi^dch *)) Index 545 I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh vii >cigdYjXi^dc 6gZndj^cVhiVi^hi^XhXaVhh4NZh4I]ZcndjcZZYi]^hWdd`#=ZgZÉhl]n/ ;VXi&/I]ZWZhilVnidaZVgchiVi^hi^Xh^hWnldg`^c\djihiVi^hi^XhegdWaZbh#I]ZgZÉh cdYZcn^c\^i#>[ndjXdjaYÒ\jgZi]^hXaVhhdji_jhiWngZVY^c\i]ZiZmiWdd`dgiV`^c\ \ddYcdiZh^cXaVhh!ZkZgnWdYnldjaYeVhhl^i]Ón^c\Xdadgh#Jc[dgijcViZan!i]Z]Vgh] igji]^hi]Vindj]VkZidWjX`aZYdlcVcYldg`egdWaZbhdjijci^andjgÒc\ZghVgZ cjbW# ;VXi'/BdhiiZmiWdd`hdcaniZaandjl]Vii]ZVchlZghidi]Z^gegVXi^XZegdWaZbhVgZ Wjicdi]dlidYdi]ZbHjgZndjgiZmiWdd`bVn]VkZ&,*egdWaZbh[dgZkZgnide^X! Wjibdhid[i]Zbdcan\^kZndji]ZVchlZgh#I]VibZVch^[ndjYdcÉi\Zii]ZVchlZg g^\]indjÉgZidiVaanhXgZlZY@cdl^c\ndjÉgZlgdc\^hcd]ZaeViVaa^[ndjYdcÉi`cdlL=N ndjÉgZlgdc\#HiVi^hi^XhiZmiWdd`hh^idcV]j\Zi]gdcZ!a^`Zi]Z<gZViVcYIZgg^WaZ DoVcYhVn!ÆCdeZ!ignV\V^c!ÇVcYndjYd#DkZgVcYdkZg!jhjVaan\Zii^c\i]ZegdWaZb lgdc\#L]ViVYZa^\]i[jalVnidaZVgcAZiÉhcdiZkZc\Zi^cidl]ni]ZndcaniZaandj i]ZVchlZghidi]ZdYYegdWaZbh#9dZhi]VibZVci]ZWdd`ÉhVXijVaVji]dgY^YcÉi ZkZc[ZZaa^`Zldg`^c\djii]ZZkZcdcZh4 ;VXi(/:kZcl]ZcbVi]Wdd`hignidh]dlndji]ZhiZeh[dgVegdWaZb!i]ZnYdV adjhn_dW#BVi]eZdeaZadkZidh`^ehiZeh#NdjÉaaWZ[daadl^c\Vadc\ÒcZl^i]VcZmeaVcVi^dc VcYi]ZcVaad[VhjYYZcWVb!ndjÉgZadhi#NdjÉaai]^c`idndjghZa[!Æ=dlY^Yi]ZnYd i]Vi4ÇdgÆL]ZgZi]Z]ZX`Y^Yi]Vi)'XdbZ[gdb4>ilVhcÉii]ZgZ^ci]ZaVhihiZeÇ L]nYdVabdhiVaad[i]ZhZWdd`hVhhjbZi]Vi^cdgYZgidldg`djiVegdWaZbdceV\Z 6aad[djg '%%!ndjÉYWZiiZg`cdleV\Zh&i]gdj\]&..a^`Zi]ZWVX`d[ndjg]VcY4NdjYdcÉilVci cdiZhVgZd[[ idheZcYi]ZgZhid[ndjga^[Zdc]dbZldg`Ndj_jhilVciid`cdll]nndj`ZZe\Zii^c\ i id]^ih]VZcYh^YeZd^ca^i`Z VcZ\Vi^kZcjbWZgl]ZcndjÉgZign^c\idXVaXjaViZi]ZegdWVW^a^ind[YgVl^c\V[jaa idi]ZeVgihd[ ]djhZ[gdbVYZX`d[XVgYh!l]^X]ndjl^aaaZVgc^c8]VeiZg*# i]ZWdd`lZÉgZ ign^c\id ;VXi)/GZVY^c\a^hihd[[VXih^h[jc[dgVl]^aZ!Wjii]Zc^i\ZihdaY#AZiÉhXjiid ZmeaV^c# i]ZX]VhZ#?jhiVWdjiZkZgnh^c\aZ`^cYd[hiVi^hi^XhegdWaZbndjXdjaYedhh^Wangjc ^cid^h^c]ZgZÅV[iZgVaa!i]^hWdd`^h]jbdc\djh>[Vi]djhVcYegdWaZbhVgZcÉiZcdj\]! i]ZcndjÉkZ\dihdbZ`^cYd[XgVonhiVih]jc\Zg!bn[g^ZcY!VcY>ÉYhZZ`egd[Zhh^dcVa ]Zae#I]^hegVXi^XZWdd`lVh\ddYViÒghi!WjiidbV`Z^i\gZVi!lZlZcii]gdj\]VcY ldg`ZYdjiVaai]ZegdWaZbhVcYidd`cdiZh^ci]ZbVg\^chl]ZclZi]dj\]ihdbZi]^c\ lVhXdc[jh^c\dgcZZYZYVa^iiaZbdgZZmeaVcVi^dc#LZVahdYgZla^iiaZh`jaahcZmiid i]Z]VgYZhiegdWaZbh!hdndjÉY`cdlcdiid[gZV`dji^[i]ZnlZgZiddX]VaaZc\^c\# 6[iZgVaa!^[ndjÉgZldg`^c\dcVegdWaZbVcYndjÉgZidiVaanhijbeZY!^hcÉi^iWZiiZgid `cdli]Vii]ZegdWaZb^hhjeedhZYidWZ]VgY4>iÉhgZVhhjg^c\!ViaZVhi[dgjh# viii I]Z=jbdc\djh7dd`d[6a\ZWgVEgdWaZbh