Steps for Analysis:
Identify the idiom (typically ~2-5 words).
Identify the purpose of the idiom.
Is it to condense information?
Is it to set a tone?
Is it being used euphemistically?
Identify the degree to which the idiom is successful in achieving its perceived purpose.
Analysis:
Freakonomics, p. 12
"'Experts'—from criminologists to real-estate agents—use their informational advantage to serve their own agenda. However, they can be beat at their own game." - Steven Levitt and Stephen Dubner
In the excerpt, the phrase "beat at their own game" is an idiom because it has a non-literal meaning different from that of the words that make it up. That is, the authors likely expect that the reader will not deduce that "experts" are actually playing a game for sport, but rather that they engage in a type of social competition in which they have an advantage over others, and that despite that advantage, one can prevail over them in that competition. By using this idiom, the authors condense a piece of information into something more quickly read and understood. It can be assumed, therefore, that the target audience of the text includes people who are familiar with common idioms such as the one used in the excerpt. Additionally, the authors use this particular idiom to further solidify their tone, as the excerpt is from the introduction of the book in which they establish their voice and style of diction. Therefore, the use of the idiom helps to maintain the light and educational tone of the text.
Benjamin McNeill