This paper is concerned with testing for causation, using the Granger definition, in a bivariate time-series context. It is argued that a sound and natural approach to such tests must rely primarily on the out-of-sample forecasting performance of models relating the original (non-prewhitened) series of interest. A specific technique of this sort is presented and employed to investigate the rela...

The need tor an aggregate abrasion test which effectively differentiates between the quality of aggregates of various unit weights prompted the development of a new test apparatus. The method selected uses air-driven sand as the abrading mechanism. Research findings based on tests of five natural and forty-seven synthetic aggregates tentatively indicate that the sandblast test is statistically ...

Incorporation of coal gangue in the concrete mixes can realize utilization solid waste and reduce extraction/use natural aggregates. To improve mechanical properties concrete, this paper studies use steel fibre together with coarse aggregate, fine aggregate/sand various mixes. The effect volume dosages different levels replacing nature aggregate river sand aggregates on compressive strength was...

For a social scientist of a particular kind, the first thought that springs to mind in association with ‘inconsistency’ is Arrow’s famous impossibility theorem. The association is a natural one because, in the original formulation, inconsistency plays a double role in Arrow’s theorem. At the first level, the requirement that any aggregate ‘community’ ranking of social states be transitive is ak...

This study examines aggregate county income growth across the 48 contiguous states from 1990 to 2005. To control for endogeneity we estimate a two-stage spatial error model and infer parameter significance by implementing a number of spatial bootstrap algorithms. We find that outdoor recreation and natural amenities favor positive growth in rural counties, densely populated rural areas enjoy st...

Collusion with Private and Aggregate Information by Jim Y. Jin* This paper considers three linear asymmetric oligopoly models with (i) a representative consumer, (ii) horizontal differentiation and (iii) vertical differentiation. We show that firms could maximize the joint-profit only based on private and aggregate information. They can choose the “correct“ colluding prices without knowing the ...

We build a heterogeneous life-cycle model which captures a large number of salient features of individual labor supply, by education, over the life cycle. The model provides an aggregation theory of individual labor supply, firmly grounded on micro evidence, and is used to study the aggregate labor supply responses to changes in the economic environment. We find that the aggregate labor supply ...

Aggregate loss functions are loss functions for counts of areas where the count itself is of interest. Proportional loss functions are loss functions for counts of areas where the count as a proportion of a total is of interest. To date, much of the work on adjustment has concentrated on aggregate loss functions. A question is whether this effort will necessarily produce estimated counts whi.ch...