How is calculated doesn’t dictate how It is used by traders. A larger member’s stock movement can influence (skew) the index, causing, traders of all the stocks in the index as whole to react, negatively or positively. If you don’t believe it don’t use, but many traders do, with great success.
Unlike the Dow Jones Industrial Average, the Russell 2000 index is weighted by shares outstanding. This means that a member stock's last sale price as well as the number of shares that can actually be traded (rather than the company's entire market capitalization) influence the index.
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