In this paper we provide the derivation of a super compact pairwise model with only 4 equations in the context of describing susceptible-infected-susceptible (SIS) epidemic dynamics on heterogenous networks. The super compact model is based on a new closure relation that involves not only the average degree but also the second and third moments of the degree distribution. Its derivation uses an...

Data from longitudinal studies may be analyzed both cross-sectionally and longitudinally. Discrepancies between estimates obtained from these analyses pose questions about the validity of cross-sectional estimates of change. In some cases these discrepancies are the result of period effects, cohort effects, or selective dropout. In others, they are the result of incomplete modeling of the proce...

This paper uses a two-sided market model to study if lastmile access providers (ISPs), should charge content providers (CPs), who derive revenue from advertisers, for the right to access ISP’s end-users. We compare two-sided pricing (ISPs could charge CPs for content delivery) with one-sided pricing (neutrality regulations prohibit such charges). Our analysis indicates that number of CPs is low...

We find a formula that relates the Fourier transform of a radial function on R with the Fourier transform of the same function defined on R. This formula enables one to explicitly calculate the Fourier transform of any radial function f(r) in any dimension, provided one knows the Fourier transform of the one-dimensional function t 7→ f(|t|) and the two-dimensional function (x1, x2) 7→ f(|(x1, x...

co-channel interference is a major factor in limiting the capacity and link quality in cellular communications. as the co-channel interference is modeled by lognormal distribution, sum of the co-channel interferences of neighboring cells is represented by the sum of lognormal random variables (rvs) which has no closed-form expression. assuming independent, identically distributed (iid) rvs, the...

the data on the effect of ethylene concentration on polymerization rate for several modifications of modern highly active titanium–magnesium catalysts ticl4/mgcl2 are presented. these catalysts differ in titanium content and conditions of support preparation, activities, and the shape of kinetic curves. it is found that the observed order of polymerization rate with respect to ethylene in the r...