Usability – Assuring Quality in Use

Marko Nieminen Professor of Usability and User Interfaces, D.Sc.(Tech.) Aalto University School of Science Department of Computer Science and Engineering SoberIT - Software Business and Engineering Laboratory

Test and Testing

•  A qualitative or quantitative procedure that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure

•  Why testing? For instance,

•  Determine if, or verify that, the requirements of a specification, regulation, or contract are met

•  Decide if a new product development program is on track: Demonstrate proof of concept

•  Validate suitability for end-use

Quality in Use – Related to Usability and User Experience

The capability of a system to enable specified users to achieve specified goals

with effectiveness, productivity, safety, and satisfaction in specified contexts of use.

Usability Test: Lab

http://www.sigchi.org/chi97/proceedings/overview/tst.htm Usability Lab at Fidelity Investments

Watching Television – On-site

Scenario: Mobile Ticketing

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Matti sees Madonna’s concert promotion at bar in Tampere

He takes a picture of promotion poster by using his mobile phone

Matti logs in to service for buying tickets. Service identifies Madonna’s concert proposition.

He buys the concert ticket and travel ticket at the same time

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…and the scenario continues

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Mikko checks his route and tickets through mobile phone

He validates travel ticket by using a mobile phone when he walks in to train at Tampere

Mikko decides to stop for one beer and buy it by using mobile phone

He validates concert ticket by using mobile phone when he arrives to gate of concert

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Field Tests

(Tamminen & Oulasvirta 2005)

Testing for ”Quality in Use” Addresses

•  Real users •  Real settings •  Real tasks •  Real events •  Real process •  Real details •  Real effects •  Real outcome

•  Expected (quantitative) and unexpected (qualitative) issues

Usability Metrics: System Usability Scale (SUS) 1.  I think that I would like to use this system frequently. 2.  I found the system unnecessarily complex. 3.  I thought the system was easy to use. 4.  I think that I would need the support of a technical person to be able

to use this system. 5.  I found the various functions in this system were well integrated. 6.  I thought there was too much inconsistency in this system. 7.  I would imagine that most people would learn to use this system very

quickly. 8.  I found the system very cumbersome to use. 9.  I felt very confident using the system. 10.  I needed to learn a lot of things before I could get going with this

system.

Sauro (2011) http://www.measuringusability.com/sus.php

Processes for Managing Quality in Use: Usability Maturity Model

•  HCD1 Ensure HCD content in system strategy •  HCD2 Plan the HCD process •  HCD3 Specify user and organisational requirements •  HCD4 Understand and specify the context of use •  HCD5 Produce design solutions •  HCD6 Evaluate designs against requirements •  HCD7 Facilitate human-system implementation

Usability – Assuring Quality in Use

Marko Nieminen Professor of Usability and User Interfaces, D.Sc.(Tech.) Aalto University School of Science Department of Computer Science and Engineering SoberIT - Software Business and Engineering Laboratory