The employer learning model postulates that employers form employees' prior ability distribution from educational credentials and update its distribution by observing workers' performance on the job. This paper estimates the employer learning model for university-graduate white-collar workers using personnel datasets from two large manufacturers that contain rich information, including the name of the university from which the worker graduated, annual performance evaluations, and position in the promotion ladder. The estimates indicate that employers learn workers' ability relatively quickly through observing their performance on the job. The initial expectation errors on ability decline by a half in about three to four years in the two companies. Companies promote graduates of elite schools quickly mainly because they tend to perform better on the job.

This note provides the closed-form solution for the model by Lazear [1]. The employer adjusts the performance standard for promotion when the employer observes only the imperfect index of the employee's ability. The adjustment margin is larger when the performance depends heavily on luck and depends lightly on the employee's ability.

Experiments of counter-current two-phase flow of upward steam flow and condensing downward film flow in a pipe were performed. The experiments were intended to examine water accumulation in steam generator U-tubes during intermediate and small break loss-of-coolant accidents of a pressurized water reactor. The inner diameter and the length of a test flow channel used in the experiments were 18 mm and 4 m, respectively. Experiments were performed at higher steam velocity a little than the velocity that was expected just after scram as the first trial. There was no water drainage form the test pipe to the lower plenum. All condensed water was entrained by steam to flow out from the top of the test pipe to the upper plenum. The test pipe was filled with the water lump and the water film, then these were blown up upward and the inner wall of the test pipe became dry. Again the test pipe was filled with the water lump and the water film, then these were blown up upward and the inner wall of the test pipe became dry. This process was iterated at short intervals. The flow state in the test pipe is highly chaotic and agitated. Condensed water flows up and down at high frequencies. It is indicated that to examine the time averaged void fraction and the two-phase pressure drop of the counter-current flow are required.