Influence for empirical transforms

Estimation procedures based on certain empirical transforms have been shown to be robust (eg. Paulson and Nicklin, 1983). Here the robustness of such procedures is examined formally using techniques derived from influence theory. Examples are given which demonstrate the easy-to-use nature of these methods. A useful by-product is a simple formula for asymptotic variances.     

Age at marriage and marital fertility

In recent years much criticism has been levelled against the use of gross and net reproduction rates as measures of replacement in any period of marked change. In this paper the author considers these criticisms and outlines a method which would yield more information on the problem of replacement and which would also eliminate the influence of varying ages at marriage on fertility when different groups or periods of time are compared. The use of this method is illustrated by an application to the fertility statistics of England and Wales and of different counties.     

Book review

Stewart, J., Econometrics. (Philip Man, London, 1991.) Pp. viii + 331. $27.95.     

Moment closure based parameter inference of stochastic kinetic models

Parameter inference for stochastic kinetic models is a topic that spans many disciplines. Although it is possible to carry out exact inference using partial observations of a stochastic process, it is often computationally impractical. In this paper we use the moment closure approximation of the underlying stochastic process as a fast approximation of the likelihood. We show that this approximation is fast and accurate, even when the population numbers are small.     

Can we,should we,measure ethnicity?

Feminist social science is marked by its diversity, its ethos of inclusiveness and its critical power. These qualities are best exemplified in feminisms' acknowledgement, at the epistemological level, that men as well as women are crucial participants in the feminist enterprise. Moreover, epistemological justifications for positioning men within feminism is matched by a commitment to think through the methodological implications of men's involvement as both researchers and researched. In particular, inclusiveness pushes at the boundary of what counts as feminist methodology, and it forces us to rethink the underlying principles of feminist research work. In this article, two key feminist methodological principles—rapport and empathy, and democracy—are interrogated in the light of a series of in-depth interviews with a group of powerful, authoritative and uniformed men (senior police officers). It is suggested that while there may be a temptation to dismiss the interviewing relations which evolved as ‘non-feminist’, they are also indicative of feminist methodological vitality and strength as well as its capacity to accommodate the fractured subjectivities of research participants. The paper concludes by positing a re-conceptualization of interviewing principles which not only appreciate diversity in feminist epistemological and methodological commitments, but also variability and difference in feminist research relationships.     

State abstinence education programs and teen birth rates in the US

Title V, Section 510 of the Social Security Act, passed in 1996 and implemented in 1998, appropriates funding to states for the purpose of educating minors on the benefits of abstinence before marriage. Despite considerable research on the impact of abstinence education on teen fertility outcomes, high quality population-level studies on state abstinence education using panel data are absent. This paper uses state-level data to analyze the impact of abstinence education on the birth rates for teens 15–17 years by evaluating the Title V, Section 510 State Abstinence Education (SAE) program. For an average state, increasing spending by 50,000/year on SAE can help avoid approximately four births to teenagers, resulting in net savings of50,000/year on SAE can help avoid approximately four births to teenagers, resulting in net savings of 15,652 to the public for each birth avoided.     

The Distribution of Sums of Certain I.I.D. Pareto Variates

ABSTRACT

Though the Pareto distribution is important to actuaries and economists, an exact expression for the distribution of the sum of n i.i.d. Pareto variates has been difficult to obtain in general. This article considers Pareto random variables with common probability density function (pdf) f(x) = (α/β) (1 + x/β)^α+1 for x > 0, where α = 1,2,… and β > 0 is a scale parameter. To date, explicit expressions are known only for a few special cases: (i) α = 1 and n = 1,2,3; (ii) 0 < α < 1 and n = 1,2,…; and (iii) 1 < α < 2 and n = 1,2,…. New expressions are provided for the more general case where β > 0, and α and n are positive integers. Laplace transforms and generalized exponential integrals are used to derive these expressions, which involve integrals of real valued functions on the positive real line. An important attribute of these expressions is that the integrands involved are non oscillating.