She discusses the key lessons of the class in this article by Sean Silverthorne, which first appeared on the HBS Working Knowledge website.

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So defining the middle class in absolute terms is hard (see article).

ECONOMIST: Burgeoning bourgeoisie

RESPONSE- Technically true, but earlier you called having Economy-plus as a 4th class of service, so stay consistent in the article.

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Attempts to generalise are complicated further by the fact that hedge funds are actually a collection of different investment strategies (see article) rather than a coherent asset class.

ECONOMIST: Hedge funds

Yet I think the Post article made a mistake in focusing simply on middle-class family breaks.

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The warning given by the article was tentative but it caused growth of the entire class to slow, and Vioxx sales growth stalled.

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Three days after a Jan. 28, 2006 Chicago Tribune article discussing the potential dangers of portable music players, Seattle class action lawyers Hagens Berman Sobol Shapiro lobbed a lawsuit at Apple on behalf of everybody who purchased an iPod in the preceding four years.

FORBES: Magazine Article

Three days after a Jan. 28, 2006 Chicago Tribune (nyse: TRB - news - people ) article discussing the potential dangers of portable music players, Seattle class action lawyers Hagens Berman Sobol Shapiro lobbed a lawsuit at Apple (nasdaq: AAPL - news - people ) on behalf of everybody who purchased an iPod in the preceding four years.

FORBES: Plaintiffs' Paradise