Emotions are the primary driver of our behavior.

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But in recent years, interest shifted to collision avoidance, hence the focus on driver behavior, the primary cause of most crashes, Dr. Campbell said.

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Mann told the panel that getting rid of unregulated "soft money" would "remove the primary incentive behind most of the offensive behavior" seen by the panel during its hearings this summer.

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And I suppose this is the primary reason that after ten days of rather bearish behavior, stocks have given back less than 2%.

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The Federal Reserve was obliging rule-based behavior that probably included making the price of gold a primary determinant in monetary policy.

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