Fixed Site Amusement Rides: Who Regulates Safety?

There is currently no national regulation of fixed site (ex. roller coaster) amusement ride safety. The current regulatory system is highly fragmented and consists of many disparate efforts by State and local agencies, judicial intervention in the form of tort litigation and industry self regulatory compliance. The Federal government has no authority over fixed site ride safety. The authors review the state of fixed site ride regulation and the merits of both centralized and de-centralized regulation, including a proposed Federal statute conferring jurisdiction of the matter upon the Consumer Products Safety Commission. They conclude with proposals for enhancing the management of fixed site ride safety.

Association between mean residual life (MRL) and failure rate functions for continuous and discrete lifetime distributions

The purpose of this study was to correct some mistakes in the literature and derive a necessary and sufficient condition for the MRL to follow the roller-coaster pattern of the corresponding failure rate function. It was also desired to find the conditions under which the discrete failure rate function has an upside-down bathtub shape if corresponding MRL function has a bathtub shape. The study showed that if discrete MRL has a bathtub shape, then under some conditions the corresponding failure rate function has an upside-down bathtub shape. Also the study corrected some mistakes in proofs of Tang, Lu and Chew (1999) and established a necessary and sufficient condition for the MRL to follow the roller-coaster pattern of the corresponding failure rate function. Similarly, some mistakes in Gupta and Gupta (2000) are corrected, with the ensuing results being expanded and proved thoroughly to establish the relationship between the crossing points of the failure rate and associated MRL functions. The new results derived in this study will be useful to model various lifetime data that occur in environmental studies, medical research, electronics engineering, and in many other areas of science and technology.