Optimal management of annual ryegrass (Lolium rigidum Gaud.) in phase rotations in the Western Australian Wheatbelt*

Lucerne (Medicago sativa L.) helps to prevent soil salinisation in the Western Australian Wheatbelt by reducing recharge to saline water tables. There is broad consensus, though, that it is not sufficiently profitable to motivate producers to plant it at the intensity at which considerable off‐site benefits would be conferred. This paper employs a multiple‐phase optimal control model to explore the value of this perennial pasture for the management of herbicide‐resistant annual ryegrass (Lolium rigidum Gaud.) in a crop–pasture rotation, given the difficulty of observing this value in practice. The availability of selective herbicides for efficient weed control is found to determine whether or not it is profitable to adopt lucerne pasture under optimal management. Herbicide resistance requires producers to employ costly, non‐selective treatments for in‐crop weed control. Thus, it motivates the adoption of perennial pasture in which cost‐effective forms of control can be implemented. Moreover, this result is robust to feasible changes in the current economic environment.     

Pierce and Haugh on characterizations of causality: A re-examination

This paper amends the set of equivalent necessary and sufficient conditions under which y does not cause x, provided by Pierce and Haugh (1977).     

Improving Statistics on International Migration in Asia

International migration has reached unprecedented scale, diversity and political, economic, social and demographic significance in Asia over the last decade. Despite this data collection of migrant stocks and flows remains very limited in most Asian countries. Accordingly, policy making on migration in the region lacks an evidence base and is influenced by interest groups, anecdotal evidence and prejudice. This paper argues that the heightened security consciousness since 911 together with the development of efficient computer based collection and analysis of migration data systems has created a propitious environment for bringing about a parametric improvement in data collection on international migration in Asia. A number of suggestions are made in this regard, especially the inclusion of relevant international migration questions in the 2010 round of population censuses.     

An economic approach to soil fertility management for wheat production in north-eastern Australia

Soil fertility decline and soil management for crop production are important economic issues for grain growers in north-eastern Australia. In that region, there is evidence of soil fertility decline which is attributed to past crop management practices. The questions addressed in this article are first, whether components of soil fertility can be improved by better management and second, by how much soil fertility would change. Soil fertility for crop production is considered in terms of soil organic carbon and nitrogen. A stochastic dynamic economic analysis of soil fertility management for wheat production is presented. A sequential analysis of first deriving the optimal nitrogen stock and application rates is followed by an assessment of tillage, stubble, and fertilizer strategies to obtain an optimal level of soil organic carbon. The recommended management practices are consistent with emerging management trends in the region. The derivation of optimal levels of soil fertility for agricultural purposes has other policy implications, which we discuss.     

Fiscal Consolidation and Decentralisation: A Tale of Two Tiers*

This paper contributes to the established literature on fiscal consolidations by investigating the distinct behaviour of central and sub‐central tiers of government during general government consolidation attempts. In the light of different degrees of decentralisation across OECD countries, and the different responsibilities devolved to sub‐central tiers, we believe that this approach offers an illuminating insight into the analysis of fiscal consolidations and their success. We show that the involvement of the sub‐central tiers of government is crucial to achieving cuts in expenditure, particularly in relation to the overall size of the government wage bill. In addition, central governments appear to exert a strong influence on the expenditure of sub‐central tiers through their grant allocations, and control of these allocations appears to have a considerable impact upon the overall success of consolidation attempts. Finally, we demonstrate that there is a skewness in cuts towards sub‐central capital expenditure both when central governments cut grant allocations and when sub‐central governments engage in lone consolidation attempts.     

Estimating unobservable valuation parameters for illiquid assets

A problem that often arises in applied finance is one where decision‐makers need to choose a value for some parameter that will affect the cash flows between two parties involved in the operation of an illiquid asset. Because the values of the cash flows also depend on various unobservable parameters, identifying the value of the policy parameter that achieves the desired allocation between the parties is no simple task, often resulting in disputes and the invocation of ad hoc approaches. We show how this problem can be solved using an extension of the well‐known ‘implied volatility’ technique from option pricing, and apply it to the determination of equilibrium rental rates on ground leases of commercial land.     

Revenue growth in not-for-profit organisations: The effects of interactive and diagnostic controls and organisational culture

Using survey and archival data for 180 not-for-profit aged care organisations, we find that interactive use of performance measurement systems positively affects the organisations’ revenue growth, while the diagnostic use negatively affects revenue growth. We also find that organisational culture, specifically attention to detail, innovation and respect for people, moderates these effects. Our findings have implications for the literature in terms of understanding the combinatorial effects of formal management control and culture on organisational performance. The findings also have practical implications for designing performance measurement systems and developing organisational cultures, to create an internal environment effective in enabling revenue growth.