Concept explainers
Study of analysts' forecasts. The Journal of Accounting Research (March 2008) published a study on relationship incentives and degree of optimism among analysts' forecasts. Participants were analysts at either a large or small brokerage firm who made their forecasts either early or late in the quarter. Also, some analysts were only concerned with making an accurate forecast, while others were also interested in their relationship with management. Suppose one of these analysts is randomly selected. Consider the following
A = {The analyst is concerned only with making an accurate forecast.}
B = {The analyst makes the forecast early in the quarter. }
C = {The analyst is from a small brokerage firm. }
Describe each of the following events in terms of unions, intersections, and complements (e.g., A∪B, A∩B, Ac, etc.).
- a. The analyst makes an early forecast and is concerned only with accuracy.
- b. The analyst is not concerned only with accuracy.
- c. The analyst is from a small brokerage firm or makes an early forecast.
- d. The analyst makes a late forecast and is not concerned only with accuracy.
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Statistics for Business and Economics (13th Edition)
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