Tool Time: Keystroke Level Modeling

KEYSTROKE LEVEL MODELING

Tool Time - Usability’s Next Top Model:

Michael Rawlins, President, Connecticut UPALori Hawkins, Sr. UX Consultant, Usability.org

Jeff Sauro, measuringusability.com June, 2011

Why this topic We’re all striving towards more agility in

the development lifecycle... Shrinking budgets inspire innovative

solutions using new tools. Stakeholders need proof ‘earlier’ in the

lifecycle... KLM is an early indicator - providing

more precision in our baselining and heuristics.

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Why explore this tool? Time to market – an increasing issue for

product development Cost of large samples no longer feasible Collaborative - even a Product Manager

can use this tool!

Level-set - The traditional lab & observation techniques are not dead... Perhaps newly augmented by leaner tools like KLM.

Proof...

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“KLM is your Canary in the Coal mine...”

Session Goals... What this tool accomplishes. KLM’s Significance in the development

lifecycle. Where best to apply... We’ll leave a lot of time for Q&A...

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What is KLM? Developed in 1983, KLM is a tool that

provides an estimation of keystrokes associated to data input tasks.

Best suited for modeling tasks less than five minutes to complete

Based primarily on modeling a sequence of operations (K, P, B, H, M, T, W)

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Operations

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Operator Characteristic Estimation

K key press and release keyboardP point the mouse to an onscreen object 1.10 seconds

B button press or release 0.10 seconds

H hand from keyboard to mouse 0.40 seconds

M mental preparation 1.20 seconds

T(n) type a string of characters (n* K seconds)

W (t) user waiting for the system to respond

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A Business Case...

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Booking a multi-city trip with Amtrak

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How to Apply… Select a working prototype Identify time-to-task goals from

stakeholders Identify main goals and sub-goals Determine happy path (and analyze) Investigate other paths... Share with stakeholders “are we

directionally correct...”

Pros… forget about the stop watch! quick and extensible share task with your stakeholders

Cons... spreadsheets can be intimating changing time estimates on operators

may require some level of research

Mitigation: Composite KLM tool

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Reference Material…

Questions…You can contact us:

michael.rawlins@gmail.com

jeff@measuringusability.com

lori@usability.org

Thank you…