Performance Evaluation:What，Why，and How?
Most members of organizations—employers and employees—embrace performance evaluation with all the enthusiasm usually shown a bad case of the flu.Few people enjoy having their work evaluated，especially when they think their pay，promotion chances，or their very jobs depend on the outcomes.Probably not many more enjoy evaluating the work of others;even if you think you know what other employees are doing is wrong，and even if you have supervisory responsibility for their work，it is seldom easy to summon the courage to tell them，no matter how constructive the criticism.A major reason for the dread most people experience in the face of performance evaluation is that organizations are more than the cool lines of authority and neat boxes that appear on organizational charts.In organizations，social relationships develop quickly;informal norms of interaction become established，often cemented by close working relationships and even friendships that pull at formal organizational roles.
Yet performance evaluation is unavoidable.As long as personnel decisions have to be made—that is，as long as choices have to be made about whom to promote or to whom to give a merit raise or whom to fire—assessments of work have to be undertaken.In fact，the only sort of organization that could avoid performance evaluation completely would be one that made all personnel decisions randomly or by reference to some arbitrary rule unrelated to quality of work.As most of us prefer not to work in organizations where decisions are made by pulling names or numbers out of a hat，we make some effort to measure one another's performance.
The key phrase here is“some effort”.Although almost all organizations evaluate their employees'performances，relatively few do so in a systematic and conscientious manner.Valid performance evaluations require hard work and a heavy commitment of the organization's time and resources.Managers must be convinced that the results of the evaluations will be useful for achieving organizational goals;employees must believe that the method of evaluation is fair and unbiased.(https://www.daowen.com)
What exactly do we mean by“systematic performance evaluation”?What distinguishes sound from unsound methods of evaluating employee performance?While no one method will be right for every job in every organization，all systems of performance evaluation worthy of the name are distinguished by one central idea:Those employee traits or behaviors—and only those employee traits and behaviors—directly related to the performance of job duties are measured.For the evaluator，this requires two kinds of information.First，he or she needs to understand the exact nature of the job;second，he or she needs to have accurate knowledge of what the job incumbent has actually been doing.The first requirement should be familiar to anyone who completed the preceding exercise.It is by reading a valid job description，based on a thorough job analysis，that evaluators know the nature of a job.More precisely，job descriptions provide detailed specifications of job duties.Each of these job duties，which in the language of performance evaluation are called job dimensions，can be used as a yardstick against which to measure the actual performance of job incumbents.
The nature of the yardstick varies widely，however.In fact，we may identify three broad types of performance appraisal systems，each of which focuses on very different measures of performance.