The authors have developed and tested scale-up methods, based on a simple social network theory, to estimate the size of hard-to-count subpopulations. The authors asked a nationally representative sample of respondents how many people they knew in a list of 32 subpopulations, including 29 subpopulations of known size and 3 of unknown size. Using these… (More)
Results from a representative survey of respondents in Florida are given, concerning their knowledge about members of their personal network, and specifically how many people respondents know in selected subpopulations. We employ a method known as a "network scale-up method". By using a collection of subpopulations of known size, and also asking about one… (More)
Accurate estimates of the sizes of certain subpopulations are needed to inform important public policy decisions in the US. Laumann et al. (1989, 1993) have attempted to assess the accuracy of the reported data on the incidence of AIDS in the US, collected by the Centers for Disease Control and published in the AIDS Weekly Surveillance Reports (AWSR) and… (More)
An individual's h-index corresponds to the number h of his/her papers that each has at least h citations. When the citation count of an article exceeds h, however, as is the case for the hundreds or even thousands of citations that accompany the most highly cited papers, no additional credit is given (these citations falling outside the so-called " Durfee… (More)
We asked respondents how many people they knew in many subpopulations. These numbers, averaged over large representative samples, should vary proportionally to the size of the subpopulations. In fact, they do not. We give two different interpretations of this finding. The first interpretation notes that the responses are linear in subpopulation size for… (More)
The Stewartson-Warn-Warn (SWW) solution for the time evolution of an inviscid, nonlinear Rossby-wave critical layer, which predicts that the critical layer will alternate between absorbing and over-reflecting states as time goes on, is shown to be hydrodynamically unstable. The instability is a two-dimensional shear instability, owing its existence to a… (More)
Ray theory is used to predict phase and group velocities for long planetary waves under realistic, albeit slowly varying, oceanic conditions. The results are compared with local theory using fields smoothed to the same amount (9Њ latitude/longitude) as well as those with much less smoothing (1Њ). The agreement is excellent, showing that local theory forms a… (More)
We apply our network scale-up model to estimate the number of people in the U.S. who know someone who experienced the terrorist attacks of September 11, 2001 and the number of people who know someone who knows someone who experienced those attacks.