What are the advantages and disadvantages of using trait, behavioral, and outcome data to measure employee performance? In your answer, discuss the level of legal defense that each method provides

What will be an ideal response?

Answer: Summary of suggested answer -
Trait appraisal instruments focus on worker characteristics, which tend to be consistent and enduring. They have the advantage of providing a shorthand behavioral system but the disadvantages of being too ambiguous and focusing on the person, not the behavior.
Behavioral appraisal instruments focus on employee behavior, what type and to what degree it is exhibited. These instruments have the following advantages: standards are concrete, focus is behavior/performance. But they also have disadvantages of: they are time consuming, it is difficult to identify key behaviors.
Outcome-based instruments measure results achieved. The most common measurement is MBO. The advantages are: results oriented, measurable. Disadvantages: a results-only focus, not all factors are controllable by employee.
Although some organizations use trait ratings, trait ratings have been criticized for being too ambiguous and for leaving the door open for conscious or unconscious bias. In addition, because of their ambiguous nature trait ratings are less defensible in court than other types of ratings. Because behaviors are unambiguous and based on observation, BARS and other behavioral instruments are more legally defensible than trait scales, which often use such hard-to-define adjectives as "poor" and "excellent." The outcome approach provides clear and unambiguous criteria by which worker performance can be judged. It also eliminates subjectivity and the potential for error and bias that goes along with it, which makes it fairly easy to defend in court.