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• Usability bezeichnet das Ausmaß zu dem ein Programm von festgelegten Benutzern verwendet werden kann, um festgelegte Ziele effektiv, effizient und zufriedenstellend in einem gegebenen Kontext zu erreichen.
  • Kontext: Benutzer, Ausgabe, Ausstattung
  • Maße: Effektivität, Effizienz, Zufriedenheit
• Ergonomie ist sowohl eine wissenschaftliche Disziplin, die sich mit dem Verständnis von Interaktionen zwischen Menschen und Systemen beschäftigt, als auch der Beruf, der die Theorie, Prinzipien, Daten und Methoden anwendet, um die Leistung eines Systems und das Wohlbefinden des Menschen, der damit arbeitet, zu optimieren.
• Usability konzentriert sich auf:
  • Benutzung
  • Aufgabe
  • Leistung
  • Aufgabenunterstützung
  • 3 Säulen
    • Usability Workshop
    • Site Visits/User Interviews
    • Usability Evaluation (Methode: Usability Inspection)
• Was wurde bei Usability falsch gemacht?
  • Design
  • Prozess
  • Benutzer
  • Kurz gesagt: Usability wurde als unwichtig abgetan, Produkt konzentriert sich nicht auf Aufgaben der Benutzer
• Usage-centered Product Design
  • Spezifikation aus Kundensicht
  • Die vier Usability-Aspekte stehen im Vordergrund
  • Modellgetrieben
    • Offen für Innovationen
    • Iterationen sind möglich, aber nicht Ziel!
  • Technologie wird komplett außen vor gelassen
  • Abgrenzung User-centered Design
  • Ablauf
    • Benutzer identifizieren (gegen Systemakteure abgrenzen)
    • Benutzerrollen modellieren
    • Aufgaben (Task Cases) identifizieren (etwas, das Akteure in ihren Rollen tun: was und warum?)
      • User intention ↔ System responsibility
    • Gruppierung der Aufgaben (Priorisierung) → Task Map, Navigation Map
    • Darstellung und Interaktionen ableiten
• User performance
  • Benutzer müssen schneller/besser mehr/neue Aufgaben lösen können
  • Hilfe bei Problemlösung anbieten, Anfänger/Experten berücksichtigen
  • Fokus auf Performance → alles zu berücksichtigen geht nicht!
  • Warum? schnellerer Einstieg, geringere Trainigs-/Supportkosten, erhöhte Effizienz/Kundenzufriedenheit, Fehlervermeidung
• Wozu methodisches Vorgehen?
  • divide and conquer
  • "Magie" aus dem Prozess nehmen → durch mehr Menschen durchführbar, delegierbar, kommunizierbar (Management)
  • Definierte Methoden sind lehr- und erlernbar und wiederholbar
  • es wird nur modelliert, was benötigt wird
• Gute Modelle
  • frei von Technologie
  • abstrakt
  • einfach
  • generalisiert
  • Konzentration auf das Wesentliche
• Task Map
  • Enthält alle Task Cases mit ihren Beziehungen zueinander.
  • Ziel ist, die Tasks zusammenzubringen, die zusammengehören um eine Aufgabe zu lösen (interaction, simple navigation)
  • Ergebnis: Mehrere Task-Cluster
• Navigation Map
  • Enthält alle Task-Cluster und die zwischen ihnen vorgesehenen Navigationspfade
  • Ziel ist, die Navigation im Programm zu vereinfachen, insb. für die zentralen Aufgaben
  • Ergebnis: Erste Struktur des Programms.
• Prototypen
  • Verfeinerung und Bewertung des Designs
  • Planung vor der Implementierung
  • Feedback von Benutzern einholen
  • Verschiedene Ansätze evaluieren
• Abstract Prototype
  • Füllt die Lücke zwischen Task-Modell und Implementierung: sonst müssten Daten/Aktionen und grafischer Entwurf in einem Schritt erledigt werden
  • bringt Daten/Aktionen in eine logische Reihenfolge/Anordnung
• Visual Prototype
  • Erste Version (passiv): Visualisierung der im AP festgelegten Reihenfolge, Test der Interaktion mit dem Benutzer, Optimierung des Designs (Idealvorstellung der Oberfläche)
  • Zweite Version (aktiv): Machbarkeit zeigen, Vorführung beim Kunden → Vorlage für die Entwicklung
• Usability Workshops
  • Anforderungen → Usability Workshop → Entwicklungsspezifikation
  • Produkt-, Projektmanager, Entwickler, Usability-Spezialist
  • Interviews/Site Visits werden durchgeführt
    • Benutzer sollen nur sagen, warum sie etwas tun, nicht wie
    • Unvorbereitetes, stummes Zuschauen bei der Arbeit kann neue Verbesserungspotentiale aufdecken
  • "low tech": Flipcharts, Karten, Pinnwände
    • Vorteile: Alles ist sichtbar, begrenzter Platz → Fokus auf zentrale Fragen, taktile Sinneswahrnehmung, einfache Arbeit (verschieben/verwerfen) und kostengünstiges Material
• Die Software-Architektur muss Usability-Aspekte berücksichtigen, da sonst evtl. benötigte Daten/Aktionen nicht an den vorgesehenen Stellen angeboten werden können
• Usability Inspection
  • Strukturierter Prozess mit Benutzer, Designer und Entwickler
  • Kann bereits auf Papierprototypen angewandt werden
  • Ziel: Defekte identifizieren, nicht beheben/diskutieren!
  • Dem Benutzer wird ein Ziel vorgegeben, nicht der Weg!
  • Wird für bestimmte Szenarien durchgespielt (mit 3-4 unterschiedlichen Benutzern je Szenario → allgemeine Defekte finden)
  • Problem: Legacy User
• Design Rules/Principles
  • Structure/Workflow (Microsoft U)
  • Logical Organization according to task
  • Association/Disassociation (lines, color, shape etc.)
  • Organization (white space, borders, alignment, size etc.)
  • Dialog boxes are bad!
• Basic Design Rules
  • support progressive usage (!)
  • provide user assistance (!)
  • learn from other errors
  • follow trends
  • good visual organization
  • communication with users

• WebDesign
  • Bad Usability Calendar
  • Top Ten Web Design Mistakes of 2005
  • WebPages That Suck
  • Ten Guidelines for User-Centered Web Design
• Usage Centered Design
  • Articles, Reports, and Papers (foruse.com)
• UI Design
  • Guidelines for using basic UI components
  • Visible Narratives: Understanding Visual Organization
  • Interface Hall of Shame
  • Usability Engineering Ensuring Customer Satisfaction (NASA)
• Office 2007
  • The Microsoft Office Fluent user interface overview
  • Julie Larson-Green - Diving into the new Office 12

What is the spectrum of Usability? What does it cover?

According to the ISO 9241-10 definition, Usability is:

Extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and statisfaction in a specified context of use.

U

sability does not only concentrate on beginners, but also takes the advanced users into account to improve the overall handling of the product for every user. Usability is about usage, task, performance, and task support. Every user should be able to reach his goals easily by using the product in a way that suits him (e.g. simple mouse clicks for beginners or keyboard shortcuts for power users).

What is the advantage of technology free wording in the design process?

By keeping the design process on an abstract level above the actual technology the results can be used to engineer a various range of actual platforms (e.g. a GUI or a display on a machine). Also the results have a longer lifetime because technology may change after a while.

What is the advantage of using a methodology for usability design?

Design is quite hard to teach because it is a creative process and you need a certain feel for it. A methodology helps designers to get theirs thoughts straight and reduce the abstract design process to a more practical process that can be understood and followed by other people.

Why do we structure in Actors, Roles, and Task Cases?

The main goal of the design process is to create a presentation and interaction design that fits the customer's needs best. To be able do that the designer needs as much information as he can get about the tasks a user of the product wants to perform. By structuring the user's interaction with the product in the above parts the designer gets a feeling for his users and what they want to do with the product. The structure gets more and more detailed from a simple definition of user groups to a detailed description of the interaction dialogs for the single tasks.

What is the main output of the task map and the navigation map?

On the task map the designer clusters all task cases that belong together to help the user in fulfilling his tasks. These clusters are then put on the navigation map to define a simple navigation between them. The result is the basic structure and organization of the product.

Why do we need an abstract prototype?

The abstract prototype closes the gap between data and action on the one hand and visual design on the other hand. In the abstract prototype the data and the actions are identified from the task cases and clustered together so that they can then be given a visual design in the visual prototype.

Why do we not ask the user for solutions, but more about his process and the workflow?

If we ask the users for solutions to their problems that will reduce innovation. Users normally tend to doing things the way they always did them and are not open for new ideas because that means they have to learn something new which is often very time consuming and leads to mistakes. If we focus on the user's workflow and even question the things he does and why he does them, we can perhaps find ways to improve his way of working with the product.

Why is it important to have the result of the system analysis as input for usability and architecture?

Usability is an essential part of the product and cannot simply be added on top of a complete product at the end. The product's architecture has to be able to support the ideas behind the usability concepts. For this reason it is important to see usability and architecture as a whole. This can only be accomplished by taking the results of the system analysis as a basis for both models and by coordinating them permanently.

What are the advantages of collaborative Usability Inspections (see http://www.foruse.com/presentations/inspections.htm)?

• members of each team (design, development, etc. especially users) are involved
• structured process → efficiency
• uncovers many different defects
• can be conducted at almost any phase of development

  • can inspect almost any deliverable or development artifact, including other sites or application versions
  • can be used repeatedly for iterative refinement of design or other deliverable

Why is the advantage to follow basic rules for design?

There are certain basic design rules that apply to every product you design (e.g. harmony of colors). If you stick to these rules you avoid making basic mistakes that are not necessary which gives you time to concentrate on the product's usability and features that go beyond these basic rules, like where to place a button or which font to choose.

• http://www.uie.com/articles/visible_narratives/
• http://vip.cs.utsa.edu/classes/cs6693s2006/lectures/cs6693week3.html

Why is it better to use more than one communication channel?

Every user is different. While one needs to read everything to understand it, the other one likes hearing spoken words more. However, stimulating different senses (at the same time) keeps the user more interested and leads to a better overall understanding.

Why do we need more than one set of principles?

A software product is a complex piece of work and has more than one side to look at. Principles that apply to the design of a user dialogue may differ from the principles that apply to the support of power user and vice versa. It is impossible to create a set of principles that cover every aspect of product design.

Why is it better to have "built-in help"?

The user wants to reach his goal quickly and without being distracted. If he needs to open a help screen and search for information regarding his current problem that costs time and the user needs to switch from help to the actual work and back. If you provide inline help (e.g. balloon tips) the user gets help without the need to explicitly search for it and is not disturbed in his work. Also, built-in help can be much more to the point than a generally written help text.

Why do most websites have bad usability?

I think most websites habe bad usability because they are not given the attention they need by the companies. Many companies still think of a website as kind of a business card and not as their representation on the internet. Also the fact that many websites are programmed by high school students who do not have the required skills to design a good website may be a reason. For many companies, a website is something you need but you do not want to pay much money for, so usability is neglected.

Find some wrong designs in products you are using! Make suggestions for improvement.

ToDo

Why should you think about trends?

If a new trend emerges and your product is the only one that has not implemented it, that would be a big problem. Programs like Microsoft Windows and Office set trends that will most likely be accepted by the mass of customers. So if you do not react to trends or even worse do not know that there are certain trends, that could lead to dissatisfied customers.

Find out the key features of Microsoft Office 2007 and the problems they want to solve compared to former solutions.

• Replaced menus with "Ribbon", Office button ("pearl) → groups commands by tasks
• Contextual tabs → commands appear in the right context (e.g. table formatting if you click on a table)
• Live previews of the available commands provide the user with a better understanding of the commands' outcome
• The Microsoft Office Fluent user interface overview - Key Features

Why does a usability engineer need so many skills?

Usability is a core feature of a software product. For this reason, a usability engineer needs to have knowledge in the field of software development and of course design itself. But he also has to convince management and other departments that usability is crucial and may not be neglected. For this reason, he needs good communication skills. He also needs to be able to feel with the customer and see the software from different perspectives to reach a certain level of usability. And nonetheless, he also needs the basis knowledge about design, ergonomics etc. to finally implement the usability.