general problem solving

General Problem Solving

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The Four Steps of Problem Solving*

• Orient• Plan• Execute• Test

These apply to any kind of problem, not just programming or process design

* [Carlson and Bloom, “The Cyclic Nature of Problem Solving: An Emergent Multi-Dimensional Problem Solving Framework”, Educational Studies in Mathematics, Vol. 58 Number 1, 2005]

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A Simple Example: Crossing the Street

• Orient: Gather information: amount of traffic, traffic lights, sirens? How does traffic work? Do cars stop for lights? Do bikes? Do pedestrians?

• Plan: Consider various approaches. What if I jaywalk? What if I walk to the corner and cross?

• Execute: Cross the street.• Check: Did I make it safely? Were there any

unexpected hazards? Should I keep using this approach or modify it next time?

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Crossing a Portland Street

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Portland Street

• Anyone who has spent time in the US can cross this street safely.

• But do note there is some construction going on, and there is a walk button (not visible in the photo) that you need to push to get a walk signal.

• If you hear a siren, you need to know to stay on the sidewalk.

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Crossing a Street in HCM City

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Hochiminh City, Vietnam

• Tourists have a very hard time crossing the street safely in HCM city. In fact there are special police to help you in the tourist areas!

• As far as I can tell, motorbikes can go through most red lights whereas cars and trucks have to stop. It is ok to cross a street full of motorbikes if you walk slowly and steadily, but never step in front of a car, bus, or truck!

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The Arc de Triomphe

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Getting to the Arc de Triomphe

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Arc de Triomphe

• The Arc is in the middle of a huge busy traffic circle

• You could get killed crossing the street over to the island where the Arc is… unless you happen to notice the underground tunnels for pedestrians!

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Oxford Street, London

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Oxford Street

• At this intersection, there is a part of the traffic light cycle where all vehicle traffic stops so pedestrians can cross. The next photo shows a similar intersection in Japan.

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Shibuya, Tokyo

Picture credit Ben Waller, bengwaller@virginmedia.com

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And the moral is…

• Follow the process! (Orient, Plan, Execute, Check)

• Don’t just jump in and start trying something! Your previous experience may not exactly apply; the best solution may not be the first thing you think of.

• Take the time to analyze the problem before you start constructing the solution. In the end you will have a better solution in less time.