DOCSLIB.ORG

California State University, Northridge the Effects Of

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
California State University, Northridge the Effects Of CALIFORNIA STATE UNIVERSITY, NORTHRIDGE THE EFFECTS OF WARNING MESSAGE HIGHLIGHTING ON NOVEL ASSEMBLY TASK PERFORMANCE A thesis submitted in partial satisfaction of the requirements for the degree of Master of Arts in Psychology Human Factors/Applied Experimental by Morris A. Zlotnik May, 1982 The Thesis of Morris A. Zlotnik is approved: Tyler Blake Ma~s. Sanders, Chair California State University, Northridge ;; ACKNOWLEDGEMENTS The author would like to acknowledge those persons who have assisted in the conception, development, and implemen­ tation of this study. I would like to thank Dr. Tyler Blake and Dr. Bill Wilsoncroft for agreeing to serve on my committiee. I would also like to thank my chairman Dr. Mark Sanders, for all the assistance he has rendered to me during this task, and especially throughout my (many) years at CSUN. My appreciation is also extended to Xyzyx Infor­ mation Corporation. Many of the documents reviewed for this study were obtained through my association with Xyzyx. In addition, the unrestricted use of their technical facil­ ities has been of invaluable help to me during the prepara­ tion of this manuscript. Finally, I would like to thank my wife Linda, for all the encouragement, patience, and love she has provided to me throughout this endeavor. This thesis is dedicated to my family and friends. i i; TABLE OF CONTENTS Page List of Figures • • v List of Tables • vi Abstract • vii INTRODUCTION • • 1 The Warning Process 2 Behavior and warnings • 3 Standardized Warnings 7 Warnings and Complex Written Procedures 10 Statement of the Problem 18 METHOD • • • 22 Independent Variables • 2.2' Dependent Variables • 25) Covariates 28 Subjects 29 Apparatus 30 Procedure 32 RESULTS 38 Multivariate Statistical Assumptions 38 Multivariate Analysis of Covariance 40 Analysis I 41 Analysis II 50 DISCUSSION • • 59 Warning Messages and Task Performance 63 Implications and Limitations • 65 REFERENCES 68 APPENDIX A • • • 72 APPENDIX B 97 APPENDIX C • 122 iv LIST OF FIGURES Figure 1. Examples of NOTE configurations currently in use. 15 2. Examples of CAUTION configurations currently in 16 use. 3. Examples of WARNING configurations currently in 17 use. 4. Representation of experimental design. 23 5. Mean task completion times for each highlighting 43 condition by cell. 6. Mean total error rate for each highlighting 44 condition by cell. 7 Mean warning message error rate for each 45 highlighting condition by cell. 8. Mean warning message recall rate for experimental 46 highlighting conditions. 9. Mean percentage correct motor operation for each 47 highlighting condition by cell. 10. Mean task completion time for control and 51 experimental groups. 11. Mean total error rate for control and 52 experimental groups. 12. Mean warning message error rate for control and 53 experimental conditions. 13. Mean percentage correct motor operation for 54 control and experimental groups. v LIST OF TABLES Table 1. Summary of recommended rules to follow when using precautinary information. 12 2. Overall tests of multivariate analysis of variance for the combined set of dependent 49 variables. 3. Source table of Roy-Bargman Stepdown analysis for experimental versus control conditions. 57 4. Source table of intercorrelations for the dependent variables. 122 vi ABSTRACT THE EFFECTS OF WARNING MESSAGE HIGHLIGHTING ON NOVEL ASSEMBLY TASK PERFORMANCE by Morris A. Zlotnik Master of Arts in Psychology A review of examples and specifications relating to emergency' and non-emergency operating procedures revealed a considerable amount of variation with respect to recom­ mended standards for highlighting of warning messages. An experiment was therefore conducted to examine the effec­ tiveness of various methods of highlighting warning mes­ sages contained in the instructions for a novel assembly task. Seventy-two male subjects screened for manual dex­ terity were randomly assigned to eight highlighting groups in a 2 X 2 X 2 factorial design. One additional non­ orthoginal group (no warning) was used as the control. The highlighting factors employed were: dimensionality (2-D vs. 3-D), cross hatching (with diagional lines), and block­ ing of the warning messages (blocked vs. non-blocked). All conditions reflected highlighting practices currently em- ployed in written procedures. Subjects read a set of as- sembly instructions in which warning message highlighting vii was varied for each group. Warning message highlighting was omitted from the control group instructions. The sub­ jects' task was to assemble a "prototype" device according to the instructions provided. The primary dependent mea­ sures were: total task completion time, total task errors, errors associated with specific warning messages, and re­ call of warning messages. In addition, the outcome of the entire task itself was used as a qualitative indication of subject performance. Findings indicated that the presence of warning messages shortened task completion time, and re­ duced total task errors and warning message errors between the experimental and control groups. No significant dif­ ferences, however, were obtained between the various high­ lighting configurations for any of the dependent measures used. Implications and limitations of this study are discussed, and suggestions for further research are made. viii INTRODUCTION Public concern for safety has increased dramatically in recent years. Major "large system" incidents such as the ThreeMile Island {TMI) accident and the DC-10 plane crash, both occuring in 1979, have brought the issue of safety to the public's attention in a dramatic fashion. Even prior to these events, the public concern for safety had been fostered by 1) the alarming increase in products liability litigation and 2) the sizable awards frequently presented to injured parties {Moll, 1976: Bry, 1978). The advent of the Consumer Products Safety Commission {CPSC) has also increased awareness by publicizing potentially hazardous products and compiling statistical data concern­ ing product related injuries. ProdUct manufacturers have both a legal and ethical obligation, given a possible hazard, to provide adequate warnings and instructions with the sale of their products. This is often accomplished by means of a label or sign at­ tached to the product and/or warning messages accompanied with the product instructions. It should be noted, howeve~ that the inclusion of these warnings with a product does not automatically relieve the manufacturer from product li­ ability. Ross {1981) cites several court cases in which the courts have ruled that warnings were inadequate because they " ••• did not adequately communicate the level of 1 2 danger, .. or ..... did not state the severity of the risk and the nature of the hazard 11 (P.35). Aside from the obvious legal obligation to warn of po­ tential hazards; warning labels are intended to lessen the risk of personal injury or property damage. Essentially this is accomplished by inducing certain patterns of behav­ ior and discouraging or eliminating other patterns of be­ havior (Dorris and Purswell, 1978). The Warning Process Previous research on visual warnings has primarily been related to traffic signage. These studies have empha­ sized such factors as interpretation (Brainard, Campbell, and Elkin, 1961); recognition, comprehension (Walker, Nico­ lay, and Stearns, 1965); readability, and visibility {King, 1975; Ells and Dewar, 1979). In many cases it is assumed that once a warning mes­ sage is received and understood, the user is capable of acting appropriately, in accordance with the message. Un­ til recently, however, capability on the part of the user was not seen as an intergral part of the warning process. Dorris and Purswell (1977) suggest that warning messages be designed to meet the following criteria: 1. The warning message must be clearly observable. 2. The warning message must be readily understood by the user. 3. The user must be willing to act in accordance with 3 the message. 4. The user must be capable of acting appropriately. The last criteria is an addition to the first three offered by Dorris and Purswell. It would seem logical that any warning could be considered ineffective, if it asked the user to perform some action the user was incapable of doing. Indeed, the courts have recognized this factor as being part of the warning process. For example, Ross (1981) cites a products liability case dealing with asbes­ tos fibers. The court ruled that a warning containing the statement to "avoid breathing the dust" was inadequate be­ cause there was no way for workers to avoid breathing as­ bestos dust (P.36). It would seem that a better understanding of the human factors that effect user responses to warnings is required. Such knowledge might aid in the development of warning mes­ sages and configurations that are more likely to induce ap­ propriate responses from users. Behavior and Warnings Most of what is known about the design of visual warn­ ings is concerned with optimizing the perception of infor­ mation i.e., receiving and understanding the information. Little research has been conducted regarding the behavioral aspects of warnings. This no doubt stems from the assumed logic that once a warning message is acknowledged by a pro­ duct user, little can be done about an individual's refusal 4 to act in accordance with the warning. This being the case, the ultimate criterion of a warning message, i.e., inducing an appropriate perceptual change in the user's be- havior, is rarely measured directly. It should be noted that some research on behavior and warnings is being per­ formed by private corporations. Unfortunately, the results of such studies are often deemed proprietary and thus un­ available to researchers outside of the corporation (Dorris, Note 1). However, there is some evidence to indi­ cate few people actually read or even recognize a product warning. Dorris and Purswell (1977) conducted an informal study on warning labels associated with a familiar object, a ham­ mer. They asked 100 subjects to use the hammer in a simple assembly task. Virtually no one noticed that warning la­ bels were affixed to the hammers.
Load more

Recommended publications
  • The Visser Chronicles
    1 Animorphs Chronicles 3 Visser K.A. Applegate *Converted to EBook by asmodeus *edited by Dace k 2 Prologue “Honey?” No answer. My husband was watching a game on television. He was preoccupied. “Honey?” I repeated, adding more urgency to my tone of voice. He looked over. Smiled sheepishly. “What’s up?” “Marco’s fever is down. I think he’s basically over this thing. He’s asleep. Anyway, I was thinking of getting some fresh air.” He muted the television. “Good idea. It’s tough when they’re sick, huh? Kids. He’s okay, though, huh?” “It’s just a virus.” “Yeah, well, take some time, you’ve been carrying the load. And if you’re going to the store- “ “Actually, I think I’ll go down to the marina.” He laughed and shook his head. “Ever since you bought that boat… I think Marco has some competition as the favorite child in this household.” He frowned. “You’re not taking it out, are you? Looks kind of gloomy out.” I made a smile. “Just want to make sure it’s well secured, check the ropes and all.” He was back with the game. He winced at some error made by his preferred team. “Uh-huh. Okay.” I stepped back, turned, and walked down the hall. The door to Marco’s room was ajar. I paused to look inside. I almost couldn’t do otherwise because the other voice in my head, the beaten-down, repressed human voice, was alive and screaming and screaming at me, begging me, pleading <No! No! No!> Marco was still asleep.
    [Show full text]
  • 124214015 Full.Pdf
    PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI DEFENSE MECHANISM ADOPTED BY THE PROTAGONISTS AGAINST THE TERROR OF DEATH IN K.A APPLEGATE’S ANIMORPHS AN UNDERGRADUATE THESIS Presented as Partial Fulfillment of the Requirements for the Degree of Sarjana Sastra in English Letters By MIKAEL ARI WIBISONO Student Number: 124214015 ENGLISH LETTERS STUDY PROGRAM DEPARTMENT OF ENGLISH LETTERS FACULTY OF LETTERS SANATA DHARMA UNIVERSITY YOGYAKARTA 2016 PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI DEFENSE MECHANISM ADOPTED BY THE PROTAGONISTS AGAINST THE TERROR OF DEATH IN K.A APPLEGATE’S ANIMORPHS AN UNDERGRADUATE THESIS Presented as Partial Fulfillment of the Requirements for the Degree of Sarjana Sastra in English Letters By MIKAEL ARI WIBISONO Student Number: 124214015 ENGLISH LETTERS STUDY PROGRAM DEPARTMENT OF ENGLISH LETTERS FACULTY OF LETTERS SANATA DHARMA UNIVERSITY YOGYAKARTA 2016 ii PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI A SarjanaSastra Undergraduate Thesis DEFENSE MECIIAMSM ADOPTED BY TITE AGAINST PROTAGOMSTS THE TERROR OT OTATTT IN K.A APPLEGATE'S AAUMORPHS By Mikael Ari Wibisono Student Number: lz4ll4}ls Defended before the Board of Examiners On August 25,2A16 and Declared Acceptable BOARD OF EXAMINERS Name Chairperson Dr. F.X. Siswadi, M.A. Secretary Dra. Sri Mulyani, M.A., ph.D / Member I Dr. F.X. Siswadi, M.A. Member2 Drs. HirmawanW[ianarkq M.Hum. Member 3 Elisa DwiWardani, S.S., M.Hum Yogyakarta, August 31 z}rc Faculty of Letters fr'.arrr s41 Dharma University s" -_# 1,ffi QG*l(tls srst*\. \ tQrtnR<{l
    [Show full text]
  • Warning Analysis for the Information Age: Rethinking the Intelligence Process
    Joint Military Intelligence College December 2003 WARNING ANALYSIS FOR THE INFORMATION AGE: RETHINKING THE INTELLIGENCE PROCESS TEL IN LIG Y E R N A C T E I L C I O M L L T E N G I E O J 1962 John W. Bodnar PCN 52518 ISBN 0-9656195-8-3 52518pref.fm Page 0 Friday, December 19, 2003 11:57 AM Warning Analysis for the Information Age: Rethinking the Intelligence Process by John W. Bodnar c Int gi c el e g ll t ii a g e r e nn tt SS cc ee rr R R o o e e f f s s e e r r a a e e t r t r n c n Joint Military c e h e Intelligence College h C Intelligence College C WASHINGTON, DC December 2003 The views expressed in this paper are those of the author and do not reflect the official policy or position of the Department of Defense or the U.S. Government 0 52518pref.fm Page ii Friday, December 19, 2003 11:57 AM The Joint Military Intelligence College supports and encourages research on intelligence issues that distills lessons and improves support to policy-level and operational consumers Warning Analysis for the Information Age: Rethinking the Intelligence Process, by John W. Bodnar This book bequeaths to the Defense Intelligence Agency, and to the Intelligence Community at large, a substantiated vision, with examples, of how analysts can exploit already-available, massive databases to tackle many of the most vexing problems that we face.
    [Show full text]
  • Read Ebook {PDF EPUB} Visser by K.A. Applegate Visser — K.A
    Read Ebook {PDF EPUB} Visser by K.A. Applegate Visser — K.A. Applegate. In an hour or so, once I was out of sight of land, I would lower my sails and wait for a Bug fighter to come lift me off the deck. The engine backwash of the Bug fighter would capsize the boat. Or / might put the Taxxon pilot to the test and see if he could ram the low-slung boat. That would puzzle the humans. Either way, my body would never be found. My time of lying low was over. I would spearhead the invasion of Earth. I would take charge of our greatest conquest. I would stand alone atop the Yeerk military hierarchy. I was to become Visser One. Her human name is Eva. There was a time when she had a loving husband and a son, Marco. When she had a wonderful career. But that was before she was infested by Edriss 562. Before the invasion of Earth. Now, Edriss 562 lives in Eva's head and controls her every movement. And through Eva, Edriss has become the highest-ranking general in the Yeerk empire, surpassing even her arch rival, Visser Three. She is Visser One. But, it has become known that Visser One's tactics for attaining her current position were less than acceptable -- even to the Yeerks. Now she is on trial for treason. If she's found innocent she'll continue to rule. But if she's found guilty, she'll lose her life -- and possibly the life of her host, Eva.
    [Show full text]
  • The Speeding of Voluntary Reaction by a Warning Signal
    Psychophysiology, 46 (2009), 225–233. Wiley Periodicals, Inc. Printed in the USA. Copyright r 2009 Society for Psychophysiological Research DOI: 10.1111/j.1469-8986.2008.00716.x PRESIDENTIAL ADDRESS, 2006 The speeding of voluntary reaction by a warning signal STEVEN A. HACKLEY Department of Psychological Sciences, University of Missouri-Columbia, Columbia, Missouri, USA Abstract Warning signals can shorten reaction time (RT) via either a top-down mechanism, temporal attention, or a bottom-up one, phasic arousal. The goal of this review article is to identify the locus at which these processes influence RT. Electrophysiological and behavioral evidence indicate that the chronometric locus for both modulatory effects lies mainly within a narrow window at the center of the stimulus–response interval. This interval presumably encompasses late perceptual, response selection, and early motor processes. Phasic arousal is theorized to reduce the threshold for response selection within a circuit involving the supramarginal gyrus. A blind-sight study indicates that conscious, cortical level processing is necessary for temporal attention, at least when the warning signal is visual. Descriptors: Temporal attention, Phasic arousal, ERP/fMRI/EMG, Parkinson’s disease, Blind sight In the field of attention and performance, warning effects used to temporal orienting is associated with a pattern of brain activation be somewhat dismissively characterized as ‘‘nonselective.’’ that differs substantially from that observed during visuospatial Whereas perceptual resources are selectively focused on ear of orienting. entry in Hillyard’s classical paradigm (Hillyard, Hink, Schwent, The study of temporal orienting began with an experiment & Picton, 1973) or on a particular visuospatial location in performed by the founder of scientific psychology, Wilhelm Posner’s paradigm (Posner, 1980), only diffuse, nonspecific Wundt (1880, pp.
    [Show full text]
  • Designing Warning Messages for Detecting Biased Online Product Recommendations: an Empirical Investigation
    Designing Warning Messages for Detecting Biased Online Product Recommendations: An Empirical Investigation Bo Xiao Information Technology Management Department, Shidler College of Business, University of Hawaii at Manoa, Honolulu, HI, United States, [email protected] Izak Benbasat Sauder School of Business, University of British Columbia, 2053 Main Mall, Vancouver, BC V6T 1Z2, Canada, [email protected] ABSTRACT The increasing adoption of product recommendation agents (PRAs) by e-commerce merchants makes it an important area of study for Information Systems researchers. PRAs are a type of web personalization technology that provides individual consumers with product recommendations based on their product- related needs and preferences expressed explicitly or implicitly. While extant research mainly assumes that such recommendation technologies are designed to benefit consumers and focuses on the positive impact of PRAs on consumers’ decision quality and decision effort, this study represents an early effort to examine PRAs that are designed to produce their recommendations on the basis of benefiting e- commerce merchants (rather than benefitting consumers) and to investigate how the availability and the design of warning messages (a potential detection support mechanism) can enhance consumers’ performance in detecting such biased PRAs. Drawing on Signal Detection Theory, the literature on warning messages, and the literature on message framing, we identified two content design characteristics of warning messages -- the inclusion of risk-handling advice and the framing of risk- handling advice -- and investigated how they influence consumers’ detection performance. The results of an online experiment reveal that a simple warning message without accompanying advice on how to detect bias is a two-edged sword, as it increases correct detection of biased PRAs (hits) at the cost of increased incorrect detection (false alarms).
    [Show full text]
  • Scholastic Relaunch Discussion Guide
    Discussion GuiDe ANIMORPHS™ by K. A. APPLEGATE DiscussinG ThE sEriEs Everyone should be scared—really scared—and that means you! Five kids— the Animorphs—are Earth’s only hope against a secret invasion by a race of terrifying parasitic aliens called Yeerks. Can the Animorphs defeat the Yeerks—and still have time to be normal kids? Stories of alien invasion have been common in science fiction novels and movies for over a century. The War of the Worlds by H. G. Wells set the standard, and has been revived over the years through a famous radio play and two movie versions. The theme has been explored by many other famous authors such as Isaac Asimov, Ray Bradbury, John Christopher, Arthur C. Clarke, and Robert Heinlein, and in movies such as Invaders from Mars, The Thing from Another World, and Invasion of the Body Snatchers, and in TV shows like Battlestar Galactica, Dr. Who, Star Trek, V, and The X-Files. In the video game, Destroy All Humans!, gamers play war-like extraterrestrials seeking to add Earth to its Galactic Empire. Now, in the Animorphs series, five young people—Jake, Marco, Cassie, Rachel, and Tobias—and one alien, Aximili-Esarrouth-Isthill (nicknamed Ax)—obtain the ability to morph into any animal they touch. They name themselves “Animorphs” and use their ability to battle a secret infiltration of Earth by the Yeerks. The Animorphs take turns narrat- ing the books, telling their story of the secret war through each of their perspectives. As you read these books you can discuss many themes that run through them—such as dehumanization, growing up, innocence, leadership, morality, responsibility, and war.
    [Show full text]
  • The Warning-Response Problem and Missed Opportunities in Preventive Diplomacy Foreword
    The Warning-Response Problem and Missed Opportunities in Preventive Diplomacy Alexander L. George and Jane E. Holl May 1997 A Report to the Carnegie Commission on PREVENTING DEADLY CONFLICT Carnegie Corporation of New York Foreword The argument that nothing can be done to prevent genocide or other forms of mass violence is increasingly unconvincing. Genocide on the scale of Bosnia or Rwanda can be anticipated and prevented. Early warning is a prerequisite both for any prudent decision to act and for effective action itself. In this concise essay, Alexander George and Jane Holl argue that leaders need the kind of warning that will induce them to act preventively, not simply warning that a bad situation is getting worse. Leaders tend to put off hard decisions as long as they can, and this has often resulted in delay or paralysis in dealing with developing crises. To prevent violent conflicts, leaders must overcome this initial policy paralysis. The events that could trigger widespread violence are usually different from the events that trigger a preventive response from outside parties. It would not, for example, have been possible to give an unambiguous, precise warning that a plane crash in Central Africa would precipitate the slaughter of nearly one million people. But many earlier indications of the possibility of genocide in Rwanda in 1994 were ignored, and no preventive plan of action was in place. As George and Holl point out, outside parties must become more receptive to warning. Early warning will not ensure successful preventive action unless there is a fundamental change of attitude by governments and international organizations.
    [Show full text]
  • Everything You Want to Know About Warnings in Less Than 2 Hours Eric
    Everything You Want To Know About Warnings In Less Than 2 Hours Eric W. Junginger Hanson Bridgett LLP 425 Market Street, 26th Floor San Francisco, CA 94105 415-995-5027 [email protected] Cal R. Burnton Steptoe & Johnson LLP 115 South LaSalle Street Suite 3100 Chicago, IL 60603 312-577-1246 [email protected] Geoffrey Peckham CEO, Clarion Safety Systems LLC 190 Old Milford Rd. Milford, PA 18337 877-748-0244 [email protected] 1 Eric Junginger is a Partner at Hanson Bridgett in San Francisco, and focuses on product liability, complex civil litigation, toxic tort cases, data breach and privacy law. He has represented a wide variety of product manufacturers and suppliers in litigation involving durable medical equipment, satellites, parachutes, asbestos, benzene, silica, air mattresses, running shoes, solar equipment, electrical motors, laboratory apparatuses, pharmaceuticals, construction equipment, consumer goods and sports equipment. He has responded to Consumer Product Safety Commission inquiries, has developed product warning language, and has worked in the legal department of the Oakland Raiders. Cal R. Burnton’s practice is in the field of complex toxic tort and product liability, earning a national reputation for his ability to manage and defend mass toxic tort and complex product liability cases with a special emphasis on high-risk matters involving novel legal, scientific, and environmental theories. He represents corporate clients in both federal and state courts in almost every state across the country. Mr. Burnton has presented seminars worldwide on product liability issues. Geoffrey Peckham, CEO of Clarion Safety Systems, chairs the ANSI Z535 Committee on Safety Signs and Colors (the committee responsible for the primary U.S.
    [Show full text]
  • Covenant and the Warnings of Hebrews: the Blessing and the Curse
    JETS 57/3 (2014) 537–53 COVENANT AND THE WARNINGS OF HEBREWS: THE BLESSING AND THE CURSE MATTHEW MCAFFEE* Anyone familiar with the literature on the warning passages from the book of Hebrews is well aware of the familiar arguments regularly put forth for and againSt the possibility that genuine believers actually apostatize. These exegetical paths are well trodden, and one would be rather presumptuous to Suggest that something new could be added to the fray this late in the game. As the title of this eSSay sug- gests, I am interested in the broader issue of covenant, particularly aS it relateS to two areas of concern: (1) the bleSSingS of covenant that memberS can be expected to receive; and (2) the curses of covenant that Stand as a warning to memberS against covenant unfaithfulness. In focusing on theSe two areaS, I am attempting to synthesize two exegetical threads I have explored elsewhere by zeroing in on their significance for the book of Hebrews, one being the covenant significance of the good word in the OT,1 the other being the high-handed Sin of NumberS 15.2 It iS my view that these two Strands of thought contribute significant insight for inter- preting the warning texts of Hebrews. I. THE COVENANT BLESSING: RECIPIENTS OF THE GOOD WORD IN HEBREWS 6:5 Hebrews 6:4–6 records one of the more familiar warning paSSageS from thiS exhortation (cf. 2:1–4; 3:6; 3:7–4:13; 10:26–39; 12:25–29) and emphasizes the fact that it is impossible for the said apostate to renew repentance.
    [Show full text]
  • The Valley of Fear
    The Valley Of Fear Arthur Conan Doyle This text is provided to you “as-is” without any warranty. No warranties of any kind, expressed or implied, are made to you as to the text or any medium it may be on, including but not limited to warranties of merchantablity or fitness for a particular purpose. This text was formatted from various free ASCII and HTML variants. See http://sherlock-holm.esfor an electronic form of this text and additional information about it. This text comes from the collection’s version 3.1. Table of contents Part I The Warning . 5 Sherlock Holmes Discourses . 8 The Tragedy of Birlstone. 12 Darkness . 16 The People Of the Drama . 21 A Dawning Light . 26 The Solution . 31 Part II TheMan.............................................................. 41 The Bodymaster . 44 Lodge 341, Vermissa . 51 The Valley of Fear . 58 The Darkest Hour . 63 Danger............................................................... 68 The Trapping of Birdy Edwards . 72 Epilogue. 76 1 PART I. The Tragedy of Birlstone CHAPTER I. The Warning am inclined to think—” said I. to guard myself. But in calling Moriarty a criminal “I should do so,” Sherlock Holmes you are uttering libel in the eyes of the law—and there lie the glory and the wonder of it! The greatest I remarked impatiently. schemer of all time, the organizer of every deviltry, I believe that I am one of the most the controlling brain of the underworld, a brain long-suffering of mortals; but I’ll admit that I was which might have made or marred the destiny of annoyed at the sardonic interruption.
    [Show full text]
  • Crying Wolf: an Empirical Study of SSL Warning Effectiveness
    Crying Wolf: An Empirical Study of SSL Warning Effectiveness Joshua Sunshine, Serge Egelman, Hazim Almuhimedi, Neha Atri, and Lorrie Faith Cranor Carnegie Mellon University fsunshine, egelman, [email protected], [email protected], [email protected] Abstract signed by an unrecognized authority. These warn- ing messages sometimes indicate a man-in-the-middle Web users are shown an invalid certificate warning or DNS spoofing attack. However, much more fre- when their browser cannot validate the identity of quently users are actually connecting to a legitimate the websites they are visiting. While these warn- website with an erroneous or self-signed certificate. ings often appear in benign situations, they can also The warnings science literature suggests that warn- signal a man-in-the-middle attack. We conducted a ings should be used only as a last resort when it survey of over 400 Internet users to examine their is not possible to eliminate or guard against a haz- reactions to and understanding of current SSL warn- ard. When warnings are used, it is important that ings. We then designed two new warnings using warn- they communicate clearly about the risk and provide ings science principles and lessons learned from the straightforward instructions for avoiding the haz- survey. We evaluated warnings used in three pop- ard [19, 22]. In this paper we examine user reac- ular web browsers and our two warnings in a 100- tions to five different SSL warnings embodying three participant, between-subjects laboratory study. Our strategies: make it difficult for users to override the warnings performed significantly better than exist- warning, clearly explain the potential danger facing ing warnings, but far too many participants exhibited users, and ask a question users can answer.
    [Show full text]