Bay Area Rapid Transit Sign System Analysis Presenter: Eric Rozell

Sign System Image from

Types of Signs SignType Bold-face wordsindex Non-emphasized wordsIndex Colored linesindex, symbol White circlessymbol Perpendicular line markersindex “Dashed” colored linesindex Airplane iconicon

Library, Cognitive, and Social Science Principles Realizes that not all travelers are “experts” – System navigable using only simple geography and pattern matching Organization of information by geography – Imagine a table of routes and stops… Signs by convention – Using colors for routes – White circles for transfer stations

Is this an “expert” system?

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Syntax, Semantics, and Pragmatics Pragmatics - Context! – Map provides geographic reference, stations provide remaining context Semantics – Do rails run actually side-by-side? – No.

Information Model

Questions?