BARS stands for Behaviourally Anchored Rating Scale is a popular parameter used by the companies to gauge the performance of its employees set against defined behaviour traits which are connected to and based on particular numeric value along a scale of 1-5. The rating scale takes into account both qualitative and quantitative aspects of performance.
Alpha is a financial measure which measures performance. It is often seen as an active return on investment and is the difference between investment and benchmark return. It is an estimated numeric value of an expected excess return of a stock relative to the return on benchmark index depending on the volatility in the market.