Human-Computer Intearction and Usability Alexander Nikov
Contents
1. is not a warning Netscape G e OR Correct because message is simply informative Slide 41 of 62 Rules for use of Colors ee TE ETEN ee e as few colors as possible as many colors as necessary e never use color as only means for information coding e never use more than 7 colors at once e use pastel colors e never use saturated colors e g intensive red intensive blue NEVER USE intensive red on intensive blue or intensive blue on intensive red Slide 42 of 62 Madrid Slide 43 of 62 Suitable Color Combinations Foreground Color Background Color black white yellow psi aa er Color combination suitable bright background colors are only suitable for displays where no flicker is visible Color combination NOT suitable either the color differences are to small thin lines not visible or the focus capabilities of the human eye are stressed Slide 44 of 62 User Guidance ISO 9241 13 e User guidance as defined in ISO 9241 13 is additional information beyond the regular user computer dialogue that is provided to the user on request or is automatically provided by the system ISO 9241 13 covers common guidance recommendations see clause 5 prompts see clause 6 feedback see clause 7 status see clause 8 error management see clause 9 on line help see clause 10 Slide 45 of 62 Negative example Feedback 1 e The user action is2. COMP 3220 Human Computer Intearction Human Computer Intearction and Usability Alexander Nikov Slide 1 of 62 HCI and Usability Introduction User test of a commercial software package Legal requirements within the European Union e ISO 9241 10 The dialog principles e ISO 13407 User centred design methods User Interface Economics Presentation of information user guidance menue design User questionaires user tests inspections Slide 2 of 62 Usability and the involved parties Software manufacturer is under competition needs to meet market requirements needs to meet legal requirements e g 90 270 EEC End user needs effective user centred quality procedures wants to get his job done needs usable product Software buyer institution intends to increase productivity needs to minimize purchase costs forgets costs of use needs to meet legal requirements e g 90 270 EEC needs certainty of usability of the purchased product Key issues e How can software be designed for usability e Which design rules are there e How to apply the rules e How can usability be integrated with quality management e How can usability be measured Slide 4 of 62 Usability is more than GUI manicure Factors determining the usability of software 60 task focus 25 consistency 15 presentation of information Source System Concepts Ltd 1997 http
3. va ocasional users of an the type and extent of possible one One Day Workshop Field application prefer menu bars ocra Symbol f their textual actions and options Ea w sable Software Packages i because of their textua i Dhjet res Standards Style Guides gc relisted presentation ni i taluation of Graphical User Interfaces GUI Footnote Functionality alone not enough anymore for lodays software packages Sofware Menu options eo Caption n Menus prevent the user from hy ad nite melita dl te Hotel I OCAR OR ABAS Mieli sfusi da within a menu Cross reference On the other hand trained and repeated leaning and active Segre dipen dre peli pepe Tre and Tabs frequent user usually go around repetition of many codes and GUI attixane of gaotio wer tiechesr GUI Praktkal deci kaowtor ing it Picture gt the menu bar to save steps e g aciual designs examples wal be provided commands 1 Text Box using shortcuts and tool bars SOO 4 S ASSE A ose File wr ind tali Object Bookmark Hyperlink Ctrl K Slide 49 of 62 Slide 50 of 62 Grouping of Menu Options Negative Example Unsorted Menu Source Microsoft Word Insert Conventional order Break laragraph Mark H n Page Numbers or a renaren Disad vantage Date and Time lo ical O rde r Comment Mark Max eight de options AutoText gt Any Character e NO grouping of options per group of option
4. Tel IBM Deutschland Mittelstand IBM Deutschland Systeme Exhibitor data IBM Deutschland Systeme IBM Informationssysteme Hall Location Booth Boothtel IBM Informationssysteme 6 G32 IBM Microelektronik Boothfax IBM Microelektronik IBM Microelektronik at Raab KarcherElectrik 22 Hits Remember Enter esc Problems no appropriate grouping of information push buttons vary in size push buttons are labelled poorly Slide 34 of 62 Clearly arranged window a r Location at CeBit 95 IBM Australia Add to Bookmarks IBM Deutschland Hall 6 i Booth G32 at Raab Karcher Elektronik Fnsi Boothtel not provided Boothfax not provided Exhibitor Address aces Tere IBM Informationssysteme Daimlerstr 21 D 71083 Herrenberg Tel not provided Fax not provided e Task related information has been grouped e Push buttons have been placed and labelled decently Slide 35 of 62 Negative Example 2 Unclearly arranged dialog box Bad continuation of dialog elements Ps Account Data IIE mecca Daa m Name John Miller ella UserID fimiller Password f ee Ra Host name Tuv Pleasanton Phone of Host 9256060163 Device Name Standard Modem z Cancel OK e The group box is not needed since the window itself is the group e The dialog box has a minimze and maximize button e The push buttons
5. The software is evaluated by a usability expert against agreed recommendations using guidelines and checklists Goals Rough analysis for non compliances with agreed recommendations such as ISO 9241 Slide 55 of 62 2 User test Usability test Prerequisites Access to representative end user and their tasks Description Typical end user perform typical tasks with the software while they are observed and recorded e g Video Goals Identification of hurdles during task completion Slide 56 of 62 3 User Interview Prerequisite Sufficient amount of experienced users of the software are available Description Experienced user of the software answer standardized questionaire e g ISONORM or SUMI Goals Rough determination of user satisfaction Slide 57 of 62 Example for User interview using standardized questionaire ISONORM Controllability Can you as a user influence the way you work with the software The software requires to follow a does not require to unnecessary strict follow a unnecessary order of operational strict order of steps operational steps Slide 58 of 62 Software manufacturer is subjected to VDT Directive Buyer of software must fulfill Views on usability VDT Directive defines defines Usable Usable product product needs needs Proof of usability ISO GEPROFT ISO 9241 ERGONOMICS 13407 Effective use
6. an from the desktop web e More than a third 36 of U K online sales took place on mobile devices in the May to July quarter according to the report Of those 82 of those took place on tablets and 18 on smartphones e The report estimates web sales across all devices including desktop and laptop for the quarter were 24 2 billion pounds 39 9 billion with mobile devices accounting for 8 7 billion 14 4 billion of the total e In 2014 mobile sales will reach 21 of total web sales for the leading 500 retailers in mobile commerce worldwide according to data in the newly published 2015 Internet Retailer Mobile 500 e Mobile sales by the world s 500 leading retailers in mobile commerce should reach 84 billion in 2014 up 80 from 47 billion in 2013 according to the 2015 Internet Retailer Mobile 500 Source http www internetretailer com 2014 09 02 mobile visitors overtake desktop visitors rthe uk September 2 2014 Slide 39 of 62 Message box types e The compatibility test completed successfully You nfo rm at i ve C h ar acte r can now make reliable disk backups AN Replace existing copy of My Favorite Document Wa rn n g C h a racte r Confusing character A is not accessible The device is not ready Critical Character Cance x Slide 40 of 62 Example for incorrect classification of a message box Netscape N No new messages on server Incorrect because no mail
7. ces sell products Increased use of computers in the environment Slide 18 of 62 Understanding Computer Technology APPLICATION SOFTWARE MAIN USER INTERACE NORMAL FLOW OF OPERATION ENTRAL PROCESSING SURGE CONTROL DEVICE OUTPUT PERIPHERALS 6 OVERFLOW INPUT OUTPUT ERROR DE BUGGING TI TOOL n a SUPPLEA DATA Slide 19 of 62 User Interface Code In a modern graphics user interface program e Estimated 40 to 90 percent of code concerned with user interface e Most estimates around 70 percent e If done wrong has to be redone If not fixed cost passed on to users User Interface Economics Good user interface may result in Increased productivity Reduced training costs Preventable user errors Reduced employee turnover User satisfaction Higher quality products produced Increased Productivity 500 menu selections per day 3 sec per selection 230 days per year 480 hours or 12 weeks Reduce the menu selection time to 1 sec 8 extra weeks out of your best people At 120K salary that lost time will cost 21K Reduced Training Costs 20 employees X 2 systems applications per year X 2 1 2 days per application 100 days or 20 weeks Training and support often more costly than hardware and software Reduced error rate 250 users avoid 1 error per week that is 0 2 error per day thereby saving 2 minutes recovery time for every avoided e
8. described before the consequence e The user is tempted to perform the action without considering the consequences Attention Xi d Press OK to delete all your files Cancel Better 7 ao The consequences are Are you sure you want to delete all your files described before the Delete required action Slide 46 of 62 Negative example Feedback 2 Attention xj e he message does not actively address J cme the user i The system will save the changes if OK is being pressed Better e User is addressed actively Do you want to save your changes Don tsave Cancel e The user control is enhanced Slide 47 of 62 Negative example Feedback 3 Attention Wrong entry e No hint towards the cause of the error e No hint towards the correct entry Better Name of application Li You must enter a number from 1 to 31 e Correct hint towards the expected entry Slide 48 of 62 Menu Dialogues ISO 9241 14 Menu Design within the Menu Bar cmon Word li Softee Earn Works bop Bir Ge em pers Format Tola Te fio i slala e The menu allows to select one item Je cecco ale out of a group of known items dini T aan SIE SE SELMI e a Menu bar Eile Edit View Insert Format Tools Table Window Help _ Leo va r Break a ti Le ea oa Esspecialy untrained and e The user gets an overview about
9. ou made to Documenti Close message of MS Wo rd adres lp 51101 Koeln peste i for Windows Address2 None Restore City Koeln Eind Seli pes na jew Source Recod jaf gt Close message of MS Excel 1 Do you want to save the changes you made to Book1 for Wind OWS The dialog has an additional Cancel Button 3 The style is inconsistent Slide 28 of 62 Quality Management QM and Usability Based on ISO 9000 ff Functionality QM traditional usability not covered Reliability gt Maintainability QM complete O Portability 6 o E UITGLCOO r A AAA tl I Basis for usability SNO requirements z lt Basis for procedures ISO 13407 Human centred design processes for interactive systems ISO 13407 Human centred software projects include e Multidisciplinary Designteams e Analysis of the context of use users tasks environment e Validation of the analysis with users e Specification of usability requirements e Development of prototypes e Evaluation of prototypes against specified usability requirements with users Slide 30 of 62 ISO 13407 User centred design processes for interactive systems Co Start of software project with multidisciplinary team Target of software project Software product meets Analyse the user s usability requirements task Evaluate prototypes against De
10. pecified users to achieve specified goals with Standard contains general effectiveness efficiency and satisfaction in a desi iteri d afan a specified context of use ISO 9241 11 Standard contains specific recommendations Effectiveness Efficiency Satisfaction 6 Questions that a user should never need to ask himself Effectiveness The accuracy and completeness with which m users achieve specified goals Where do come from ba l e How did get here Efficiency The resources expended in relation to the accuracy and completeness with which users e Where am I achieve goals e What can do here isfaction Fr m from discomfort an iti Satisfactio eedom from discomfort and positive e Where can go from here attitudes to the use of the product e How do get out of here Context of use The users tasks equipment hardware software and materials and the physical and social environments in which a product is used Slide 15 of 62 Slide 16 of 62 Principles of user interface design according to ISO 9241 10 The seven dialogue principles suitability for the task suitability for learning self descriptiveness suitability for individualization conformity with user expectations error tolerance controllability Slide 17 of 62 Importance of Good User Interface Design Reduction in coding costs High costs of interface problems Serious life threatening errors Good interfa
11. r centred design process TUV Rheinland APPROMED Product Safety Slide 59 of 62 Test procedure for software products Product description Who are the users User manual What are their key tasks Documentation Product Context of use Representative users e Task scenarios e Observation and identification Inspection of usability problems Inspection of attributes through usability expert Conformance Deviation report Final evaluation of the software product Slide 60 of 62 Usability control Development process
12. rive usability requirements usability requirements Develop prototypes ISO 9241 12 Presentation of information e General guidance e how to organize information e Use of coding techniques Summary e Display only task related information e The task requirements determine the screen layout Spare usage of attributes underline blinking colour etc Slide 32 of 62 ISO 9241 12 Principles for presenting information Tn 4 NS Clarity the information content is conveyed quickly and accurately e Discriminability the displayed information can be distinguished accurately Conciseness users are given only the information necessary to accomplish the task e Consistency the same information is presented in the same way throughout the application according to the user s expectation e Detectability user s attention is directed towards information required e Legibility information is easy to read Comprehensibility meaning is clearly understandable unambiguous interpretable and recognizable Slide 33 of 62 Negative Example 1 Unclearly arranged window ia Exhibitor Selection Dx Name ibm IBM Australia IBM Deutschland IBM Deutschland IBM Deutschland IBM Informationssysteme IBM Deutschland Informationss Daimlerstr 21 IBM Deutschland Informationss IBM Deutschland Informationss CETTE de IBM Deutschland Informationss IBM Deutschland Informationss
13. rror 220 working days 75 salary per hour 250 x 0 2 x 220 x 2 5 error 27 500 saved per year Slide 24 of 62 Reduced implementation costs Given a usability defect an early design change is then about 1 4 cost of a late implementation change This holds for an inhouse project 20 changes made during design 8 hours needed per change 150 salary per hour Design change costs 20 x 8 x 150 24 000 Implementation change costs 4 x design costs 96 000 Total cost savings 96 000 24 000 72 000 Slide 25 of 62 Negative example Not self descriptive dialog Source Microsoft Word Data Form x Title None OK FirstName Thomas eae LastName Gis Jan JobTitle Human Factors Analyst __ Delete Company TUY Rheinland Restore Address1 D 51101 Koeln Find Address2 Boe City koen O View Source State emy gg Record M 4 gt DI Problem The dialog can only be aborted through the window menue or the escape key The button Cancel is missing For novice users who do not know the window menue the dialog is not even controllable Self descriptive Dialog Source T V Rheinland Negative example Dialog does not conform with user expectations Source MS Office Data Form 2 x Title None z _ x FirstName Tho mas ancel obTitle Human Factors Analyst Add New 7 man TUV Rheinland el IN Do you want to save the changes y
14. s anne O l Any Digt Symbol logical order of use aa e no structured search possible ae v uni cena arn Em Dash e long search time Divider between Caption q y sal Mark groups of options Cross reference Field _ tesa Choose clear titles Dati Graphic Picture gt i Manual Line Break Text Box Fie e represent objects by noun ati Object Nonbreaking Space Bookmark z Optional Hyphen Hyperlink Ciri k represent actions by verbs Section Break White Space Slide 51 of 62 Slide 52 of 62 Sorted menu in accordance with ISO 9241 14 Source TUV Rheinland Jaragraph Mark P reer e Options are grouped Comment Mark a a i BNR e maximum of 8 options per group of options Endnote Mark i we Footnote Mark most frequent used options are positioned at the start of the Any Character option group Any Digit Any Letter Field Graphic Ad Va ntage i White Space i ont satongex Grouping supports faster identification of searched objects Column Break Manual Line Break minimized search time Manual Page Break Slide 53 of 62 Evaluation of usability A Practically three methods available 1 Expert evaluation asking usability expert 2 User test testing with users 3 User interview asking users Slide 54 of 62 1 Expert evaluation Prerequisites e Knowledge about the user group and their tasks e Familiarity with the evaluated software Description
15. table for the task Nena Software must be easy to use and where appropriate adaptable to the operator s level of knowledge or experience systems must provide feedback to workers on their performance systems must display information in a format and at a pace which are adapted to operators the principles of human computer interaction must be applied in particular to human data processing Slide 11 of 62 ISO 9241 Ergonomic requirements for office work with visual display terminals Part 1 General Introduction Part 2 Guidance on task requirements Part 3 Visual display requirements Part 4 Keyboard requirements Part 5 Workstation layout and postural requirements Part 6 Environmental requirements Part 7 Display requirements with reflections ai l Part 8 Requirements for displayed colours Part 9 Requirements for non keyboard input devices Part 10 Dialogue principles sisa Part 11 Guidance on usability Part 12 Presentation of information Part 13 User guidance Part 14 Menu dialogues Part 15 Command dialogues Part 16 Direct manipulation dialogues Part 17 Form filling dialogues ue Slide 12 of 62 The structure of ISO 9241 parts 10 to 17 Definition of usability Part 11 Effectiveness Efficiency Satisfaction Legend Part 10 Dialogue principles Standard contains general cc ee a a The extent to which a product can be used by Presentation of information s
16. vary in size Slide 36 of 62 Clearly arranged dialog box a Account Data X Account Data X User Ok Connection OK Name John Miller Cancel Host name muy Pleasanton Cancel User ID jmiller Phone of Hast 32560601 63 XXXXXXXXXX Help 5 Help Device Name Standard Modem X The dialog box employs property sheets to group information Slide 37 of 62 User Interface Styleguides The Windows Interface Guidelines for Software Design Microsoft Corporation ISBN 3 86063 226 4 HTML Version on the Web www microsoft com win32dev uiguide Macintosh Human Interface Guidelines Apple Computer Inc Addison Wesley Publishing Company 1992 ISBN 0 201 62216 5 Object Oriented Interface Design IBM Common User Access Guidelines CUA IBM Corporation published by Que Corporation 11711 N College Avenue Carmel IN 46032 1992 ISBN 1 56529 170 0 Slide 38 of 62 Mobile visitors to retail sites overtake desktop visitors in the U K e 52 of retail site traffic now originates on tablets or smartphones and transactions from those devices account for more than a third of U K web sales e U K consumers in Q2 2014 more often turned to their mobile devices than their computers to connect with retailers with 52 of traffic to retail web sites coming from smartphones and tablet computers e It was the first time U K retailers received more web traffic from mobile th
17. www system concepts com articles gui html Slide 5 of 62 Usability under interface Menus LE User interface Feedbacks Input fields Va Information groups Requirements acquisition Task analysis Slide 6 of 62 European VDT Directive http europa eu int eur lex en lit dat en_390L0270 html Council Directive of 29 May 1990 on the minimum safety and health requirements for work with display screen equipment 90 270 EEC S 9 5th individual Directive within the meaning of Article 16 1 of Directive 89 391 EEC Slide 7 of 62 European VDT Directive Enforcement in Europe 12 June 1989 29 May 1990 Framework directive on 5 rm health and safet SU ec Dire cive 21 Aug 1996 Slide 8 of 62 European VDT Directive The requirements Minimum requirements on Hardware monitor keyboard work desk work surface work chair Environment space requirements lighting reflections and glare noise heat radiation humidity Software Operator Computer Interface Slide 9 of 62 European VDT Directive Who is addressed Employers in Europe who are operating computer work places Buyers of IT equipment within companies organisations Who is indirectly addressed Manufacturers of Hardware equipment Manufacturers of software Slide 10 of 62 European VDT Directive Software requirements e Software must be sui
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