British Children and Televised Violence

Is the frequency of watching television programs with recurrentviolent themes positively related to aggressive attitudes amongyoung people? This study of a sample of British school childrenyields findings very similar to U.S. data, in terms of bothdirection and magnitude of the relationship. It also examinesthe influence of program type and demographic variables on thatrelationship.     

First passage game

Appealing to the theory of stochastic games, a two-person, zero-sum first passage game, which may be viewed as a generalization of the first passage decision problem, is developed. In the first passage game, the players have stationary optional strategies and the values are unique and these can be computed using an algorithm for terminating stochastic games. It is also shown that the solution of a recurrence game is closely related to that of the first passage game. Finally, it is shown that a finite step stochastic game with nonstationary transition probabilities and payoffs can be converted to a first passage game whose solution yields a solution of the original finite step game. The first passage game so obtained has stationary transition probabilities and payoffs. Because of its special structure, the solution method reduces to a dynamic programming recursion in the context of games.     

Risk Assessment for Carcinogens Under California''s Proposition 65

Risk assessments for carcinogens are being developed through an accelerated process in California as a part of the state's implementation of Proposition 65, the Safe Drinking Water and Toxic Enforcement Act. Estimates of carcinogenic potency made by the California Department of Health Services (CDHS) are generally similar to estimates made by the U.S. Environmental Protection Agency (EPA). The largest differences are due to EPA's use of the maximum likelihood estimate instead of CDHS' use of the upper 95% confidence bounds on potencies derived from human data and to procedures used to correct for studies of short duration or with early mortality. Numerical limits derived from these potency estimates constitute "no significant risk" levels, which govern exemption from Proposition 65's discharge prohibition and warning requirements. Under Proposition 65 regulations, lifetime cancer risks less than 10(-5) are not significant and cumulative intake is not considered. Following these regulations, numerical limits for a number of Proposition 65 carcinogens that are applicable to the control of toxic discharges are less stringent than limits under existing federal water pollution control laws. Thus, existing federal limits will become the Proposition 65 levels for discharge. Chemicals currently not covered by federal and state controls will eventually be subject to discharge limitations under Proposition 65. "No significant risk" levels (expressed in terms of daily intake of carcinogens) also trigger warning requirements under Proposition 65 that are more extensive than existing state or federal requirements. A variety of chemical exposures from multiple sources are identified that exceed Proposition 65's "no significant risk" levels.     

World population trends in 1960-70

The rapid rise in world population for the 4 periods 1950-1955, 1955 -1960, 1960-1965, and 1965-1970 is mainly due to a decline in the crude death rate from 24/1000 in 1950-1955 to 16.1/1000 in 1965-1970. 1950 was a turning-point in mortality rates because for the first time public health measures became widely available in less developed regions. These less developed regions contained 63.4% of the world population in 1930, 65.5% in 1950, and 70.0% in 1970. World population increased by 22% in 1960-1970, compared to 20% in 1950-1960, which was twice as much as the 20% registered for the 20 years 1930-1950. Developed regions contributed a 14% increase between 1950-1960 and 12% between 1960-1970; in less developed regions the increases were 23% and 27% respectively. Demographic conferences have begun to neglect mortality, but this is still a vital part of total population growth. Evidence is that the mortality decline in less developed countries is beginning to level off so that previous population projections may not be reached. What decline has been seen in crude birth rates in less developed countries is largely attributable to declines in East Asia, notably in the People's Republic of China, Republic of Korea, and other Chinese or Chinese culture-related populations, as well as some of the smaller Latin American countries and some small islands off Africa. Such demographic giants as India, Indonesia, Pakistan, and sub-Saharan Africa have shown little change. In areas with high fertility there are more mothers under age 20 and more births to women over age 35 while in low-fertility areas births are concentrated in the 20-35 year groups. An interesting example is Japan which has 50% of its births to mothers 25-29 years of age. Less developed countries have a larger proportion o f the population under age 14 while developed countries which have had lower fertility for a number of years have larger numbers in the older age groups. In less developed areas the greatest burdens are associated with child-rearing while welfare for the aged is the great concern in the more developed areas of the world. The great trend toward urbanization in all parts of the world means that the population problems commanding greatest attention are those associated with large and fast-growing cities.