Performance appraisals are an essential tool for organizations to evaluate their employees' performance. However, measurement errors can significantly affect the accuracy and validity of these appraisals. There are several types of measurement errors that can occur during the evaluation process, including central tendency errors, leniency, halo effect, recency effect, and personal bias.

Central tendency errors occur when the evaluator rates all employees as average, regardless of their actual performance.

Leniency errors happen when the evaluator gives high or low ratings to all employees, respectively, regardless of their actual performance.

Halo effect occurs when the evaluator's overall impression of the employee affects their rating on specific areas, regardless of their actual performance.

Recency effect occurs when the evaluator only considers the employee's recent performance, ignoring their overall performance.

Personal bias occurs when the evaluator's personal opinions or prejudices affect their assessment of the employee's performance.