Preferred Workflows for Syndromic Surveillance Systems

Workflows are a sequence of information processing operations that people carry out to meet certain in-formational goals [1]. Using various user-centered design (UCD) techniques we uncovered the workflows that epidemiologists wished to follow when using syndromic surveillance (SS) systems

Can Ex Post Rates of Return Detect Monopoly Profits?

We review the ability of the ex post internal rate of return (IRR) to detect monopoly profits. When market values are used as entry and exit values the ex post IRR simply reveals whether the firm did better or worse than the market expected at the entry date. It says nothing about monopoly profits. When replacement costs are used as entry and exit values the ex post IRR can in principle reveal something about monopoly profits. However since the ex post IRR is a noisy measure of ex ante monopoly profits it will be very difficult to reject the hypothesis given the sample periods typically available. The benchmarks typically used are market-determined and therefore only comparable to IRRs calculated using market values - a situation when the ex post IRR reveals nothing about monopoly profits anyway. Furthermore there is ample empirical and theoretical evidence that these benchmarks do not even represent fair rates of return

Payback Without Apology

When interest rates are uncertain the net-present-value threshold required to justify an irreversible investment is increasing in the length of a project's payback period. Thus slowpayback projects should face a higher hurdle than fast-payback projects just as investment folklore suggests. This result suggests that the widely disparaged use of payback for capital budgeting purposes can be an intuitive response to correctly perceived costs and benefits

Can Ex Post Rates of Return Detect Monopoly Profits?

We review the ability of the ex post internal rate of return (IRR) to detect monopoly profits. When market values are used as entry and exit values the ex post IRR simply reveals whether the firm did better or worse than the market expected at the entry date. It says nothing about monopoly profits. When replacement costs are used as entry and exit values the ex post IRR can in principle reveal something about monopoly profits. However since the ex post IRR is a noisy measure of ex ante monopoly profits it will be very difficult to reject the hypothesis given the sample periods typically available. The benchmarks typically used are market-determined and therefore only comparable to IRRs calculated using market values - a situation when the ex post IRR reveals nothing about monopoly profits anyway. Furthermore there is ample empirical and theoretical evidence that these benchmarks do not even represent fair rates of return

My Kingdom for a Horse: Resolving Conflicts of Interest in Asset Management

Racehorse trainers operate asset management businesses in which the assets owned by outside clients compete with those owned by managers for the latter's time care and attention. Although this potentially leads to serious conflicts of interest we find no evidence of an agency problem: in a sample of 8000 racehorses and their associated stables client-owned horses perform no worse than trainer-owned horses on average. However this outcome is not uniform across stables: the average performance advantage of client-owned horses over their trainer-owned counterparts is positive in big stables where client-owners provide much of the trainer's income but is negative in small stables with relatively few outside clients. Agents with more to lose apparently behave better

Estimating Implied Valuation Parameters: Extension and Application to Ground Lease Rentals

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 such as a rental rate or an exercise price. 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

Evaluating African horse sickness virus in horses and field-caught Culicoides biting midges on the East Rand, Gauteng Province, South Africa

A prospective study was undertaken during 2013 and 2014, to determine the prevalence of African horse sickness virus (AHSV) in Culicoides midges and the incidence of infection caused by the virus in 28 vaccinated resident horses on two equine establishments on the East Rand, Gauteng Province, South Africa. Field caught Culicoides midges together with whole blood samples from participating horses were collected every two weeks at each establishment. Culicoides midges and blood samples were tested for the presence of AHSV RNA by real-time quantitative reverse transcription polymerase chain reaction. Nine immunised horses became infected with AHSV during the study period, although infections were subclinical. African horse sickness virus was also identified from a field-collected midge pool. The observations recapitulate previously published data in another setting, where further investigation is warranted to determine what role subclinical infection plays in the diseases epidemiology

My Kingdom for a Horse: Resolving Conflicts of Interest in Asset Management

Racehorse trainers operate asset management businesses in which the assets owned by outside clients compete with those owned by managers for the latter's time care and attention. Although this potentially leads to serious conflicts of interest we find no evidence of an agency problem: in a sample of 8000 racehorses and their associated stables client-owned horses perform no worse than trainer-owned horses on average. However this outcome is not uniform across stables: the average performance advantage of client-owned horses over their trainer-owned counterparts is positive in big stables where client-owners provide much of the trainer's income but is negative in small stables with relatively few outside clients. Agents with more to lose apparently behave better