How to Use Five Letterforms to Gauge a Typeface's Personality: A Research-Driven Method
http://baywood.metapress.com/link.asp?target=contribution&id=LQVLEJ9Y1LRX7C95
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  peer-reviewed

Mackiewicz, Jo M.
Journal of Technical Writing and Communication
2005

Abstract:

Technical communicators need to select typefaces that match the tone that they intend for a document. Rather than relying on intuition or personal preference, technical communicators can use a research-driven approach to analyze objectively the extent to which a typeface's personality meshes with the intended tone of a document. This study describes how technical communicators can analyze a typeface's uppercase J and its lowercase a, g, e, and n letterforms--letterforms that are dense with anatomical information-- to gauge the extent to which a typeface will contribute a friendly or a professional personality to a document. Technical communicators--both professionals and students--who are armed with this knowledge can move beyond "safe" typefaces like Times New Roman and Helvetica, selecting instead typefaces whose anatomical features generate different kinds of personalities.