Predicting mortality over different time horizons: which data elements are needed?

Which elements of a finite group are non-vanishing?

‎Let $G$ be a finite group‎. ‎An element $gin G$ is called non-vanishing‎, ‎if for‎ ‎every irreducible complex character $chi$ of $G$‎, ‎$chi(g)neq 0$‎. ‎The bi-Cayley graph ${rm BCay}(G,T)$ of $G$ with respect to a subset $Tsubseteq G$‎, ‎is an undirected graph with‎ ‎vertex set $Gtimes{1,2}$ and edge set ${{(x,1),(tx,2)}mid xin G‎, ‎ tin T}$‎. ‎Let ${rm nv}(G)$ be the set‎ ‎of all non-vanishi...

Which elements of the criteria for RA are stable over time?

Rings in which elements are the sum of an‎ ‎idempotent and a regular element

Let R be an associative ring with unity. An element a in R is said to be r-clean if a = e+r, where e is an idempotent and r is a regular (von Neumann) element in R. If every element of R is r-clean, then R is called an r-clean ring. In this paper, we prove that the concepts of clean ring and r-clean ring are equivalent for abelian rings. Further we prove that if 0 and 1 are the only idempotents...

Excellence in primary care research: which requirements are needed?

in most European countries is the equivalent of primary care), Barbara Starfield’s proposal is still the most plausible and appropriate: she described primary care as firstcontact, continuous, comprehensive, and coordinated care provided to populations undifferentiated by gender, disease, or organ system. These elements are accepted by most professional organisations, agencies and commissions a...

An Assessment of Combining Tourism Demand Forecasts over Different Time Horizons

This study investigates the performance of combination forecasts in comparison to individual forecasts. The empirical study focuses on the UK outbound leisure tourism demand for the USA. The combination forecasts are based on the competing forecasts generated from seven individual forecasting techniques. The three combination methods examined in this study are: the simple average combination me...