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NCJ Number
R P Harker
Date Published
6 pages
This paper discusses the nature and purpose of the "line" in sports betting.
The "line" theoretically functions as a handicap to balance the relative strengths of the opposing teams. It consists of points either added to the underdog teams' final scores or subtracted from the favorite teams' final scores. Having theoretically balanced the relative strengths of the teams, wagers are accepted by bookmakers usually at 11-10 odds. From the bookmaker's perspective, the purpose of the line is to attract relatively even amounts of wagering on both sides of the contest. If the bookmaker achieves an even balance of wagering on a game and has no gamble or risk, profit is assured of being 10 percent, the "juice" or "vigorish" of the losing wagers. The line is typically developed in Las Vegas, where its public posting is permitted in legal bookmaking establishments. Those who post the line in Vegas also have vast sources of information about the games. When bookmakers obtain the line from Vegas, they adjust it to take into account local betting patterns. A bookmaker may change the line as the betting progresses so as to stimulate more balanced betting on the teams. If the bookmaker cannot achieve balanced betting through reasonable line changes, he may "layoff" (bet with another bookmaker so as to ensure a profit regardless of which team wins). The line achieves its purpose by attracting wagers and helping to ensure the bookmaker makes a profit on each game. 5 figures