The parabolic SAR is a technical indicator that is used by many traders to determine the direction of an asset's momentum and the point in time when this momentum has a higher-than-normal probability of switching directions. Sometimes known as the "stop and reversal system", the parabolic SAR was developed by the famous technician Welles Wilder, creator of the relative strength index, and it is shown as a series of dots placed either above or below an asset's price on a chart. 

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