0 Se p 20 02 The Dynamical Parameters of the Universe
The results of different analyses of the dynamical parameters of the Universe are converging towards agreement. Remaining disagreements reflect systematic errors coming either from the observations or from differences in the methods of analysis. Compiling the most precise parameter values with our estimates of such systematic errors added, we find the following best values: the baryonic density parameter Ω b h 2 = 0.019 ± 0.02, the density parameter of the matter component Ω m = 0.29 ± 0.06, the density parameter of the cosmological constant Ω λ = 0.71 ± 0.07, the spectral index of scalar fluctuations n s = 1.02 ± 0.08, the equation of state of the cosmological constant w λ < −0.86, and the deceleration parameter q 0 = −0.56 ± 0.04. We do not modify the published best values of the Hubble parameter H 0 = 0.73 ± 0.07 and the total density parameter Ω 0 +0.03 −0.02 .
A Cosmological Model
(I) IT is familiar that the Einstein equations for the density and pressure in a uniform universe: do not suffice to specify the model since there are two equations and three unknown functions, ρ, p and R. A very common assumption is p = 0, but models involving both positive and negative values of p have also been proposed. McCrea1 pointed out that there is no objection in principle to negative pressure and that the steady-state universe can be interpreted in this way.
Definitions of efficiency
This is the third in a series of occasional notes on economics

Decision makers are increasingly faced with the challenge of reconciling growing demand for health care services with available funds.1 Economists argue that the achievement of (greater) efficiency from scarce resources should be a major criterion for priority setting. This note examines three concepts of efficiency: technical, productive, and allocative.

Efficiency measures whether healthcare resources are being used to get the best value for money.1 Health care can be seen an intermediate product, in the sense of being a means to the end of improved health. Efficiency is concerned with the relation between resource inputs (costs, in the form of labour, capital, or equipment) and either intermediate outputs (numbers treated, waiting time, etc) or final health outcomes (lives saved, life years gained, quality adjusted life years (QALYs)). Although many evaluations use intermediate outputs as a measure of effectiveness, this can …