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Nuisance or unwanted calls have always been a problem to subscribers of phone services. One possible solution is a network based service that allows subscribers to control the calls they receive by using a call acceptance list. When the call acceptance list is activated, all callers not on the list would be automatically routed to a voice messaging system. Those callers on the list would be allowed to ring the subscriber's telephone. This study assessed the effectiveness of call acceptance lists in reducing unwanted telephone calls. Participants used a prototype telephone-based interface to establish a list of telephone numbers from which they would always accept calls. At the same time, they logged each of their incoming calls in a diary, recording the telephone number that originated the call, and whether they wished to receive the call. The call acceptance list significantly reduced the number of unwanted calls from 12% to 1%. However, this list also substantially reduced the number of wanted calls answered by the subscriber from 88% to 33%. Although a call acceptance list appears to be effective in blocking unwanted calls from reaching the subscriber, the list would also route a substantial number of wanted calls to voice messaging. If the majority of the calls are wanted, the results of this experiment suggest that a call rejection list would be a more effective method for preventing unwanted calls. Fewer wanted calls would be rejected while preventing unwanted calls from ringing through.

This study surveyed 342 directory-assistance @A) operators regarding the text and background colors they used to display directory listings on their computer workstations. Color combinations were observed in use, recorded, and scored based on independent, published subjective ratings of color comfort and edge sharpness. Operators also answered a questionnaire that included information about: how often they changed colors and if they had experienced eye problems. No relationships were found between selfreported eye problems and observed color choices. However, operators using color combinations that were scored low on either comfort, edge sharpness, or both, were more likely to change the colors on their screens more frequently. This result provides evidence that independent ratings can provide practical guidance in making color recommendations.

Ideally, information should be distributed among storage devices according to how frequently it is accessed. Rarely accessed information should be stored on the cheapest (and slowest) devices, frequently accessed data should be store on the fastest (and more expensive) devices.