Post-hoc testing

IST 331 - Olivier GeorgeonApril 22nd 2010

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• Human nature is not a machine to be built after a model - and set to do exactly the work prescribed to it - but a tree, which requires to grow and develop itself on all sides, according to the tendency of the inward forces which make it a living thing.

John Stuart Mill, On Liberty (1859)

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Evolutionist process

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Design Use

Why post-hoc testing?

• Avoid recalls.• Identify target.• Identify need for formation or documentation.• Final setup.• Evaluate the design.• Because all people (including designers) make

mistakes (i.e. user-testing can be used as a type of proof-reading).

• Provide feedback for the next iteration.

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Methods

• Same method as preliminary studies– Questionnaires and Interviews– Observational studies• Verbal protocol• Visual protocol

– Use unsolicited comments

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Activity analysis tools

• Noldus– http://www.noldus.com

• Interact– http://www.mangold-

international.com/

• Abstract– http://liris.cnrs.fr/abstract/

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Example

Local

Youtube

8Youtube

[1][2][3][4][5][6][7][8][9][10][11]

4/3/1970 5/20/2007

1/10/1973

[1] Ulster Volunteer Force (UVF)[2] Ulster Freedom Fighters (UFF)[3] Protestant Extremists[4] Loyalist Volunteer Forces (LVF)[5] Red Hand Commandos

[1][2][3][4][5][6][7][8][9][10][11]

[7] Irish National Liberation Army (INLA)[8] Saor Eire (Irish Republican Group)[9] Official Irish Republican Army (OIRA)/[10] Irish People's Liberation Organization (IPLO)[11] Irish Republican Army (IRA)

[6] Unknown

Republic of Ireland

Conclusion

• Interface design is an evolutionist process.• Post-hoc evaluation also matters.

• Lot of room for IST research.

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