Take a risk: Preferring prevention over control of biological invaders

Scientists have argued that invasive species can be managed most cost effectively with greater investments in prevention. Further, under ideas like the precautionary principle it is reasonable to expect that a cautious manager would use more prevention relative to control because it keeps more invaders out. Yet, this is not typically done. In many cases, private and public resources are invested primarily to control existing invaders rather than to prevent new invasions. Managers frequently wait until after invaders have arrived and then scramble to limit the damages. We believe these paradoxical decisions can be understood by recognizing the link between typical human preferences for risk bearing and the technology of risk reduction. We demonstrate quantitatively how managers perceived to be cautious or averse to risk tend to shy away from prevention relative to control. This counterintuitive result arises because control is a safer choice than prevention because its productivity is relatively less risky: it works to remove existing invaders from the system. In contrast, the productivity of prevention is more uncertain because prevention only reduces the chance of invasion, it does not eliminate it, and invasion may not occur even in the absence of prevention. Managers' averse to risk will inherently avoid as much uncertainty as possible, whether the source of uncertainty regards ecological outcomes or economic productivity. Implications for environmental decision making are clear. In invasive species management, if managers act as though they are risk averse, their caution can backfire when it leads to more control rather than prevention. The social consequences of this choice are a greater probability of future invasions and lower social welfare. Our results suggest that social welfare is highest when managers were willing to “take a risk” with prevention.     

Cooperative and noncooperative protection against transferable and filterable externalities

Given self-protection from an undesirable environmental externality, we examine, under several conditions, the efficiency properties of cooperative and noncooperative behavior. We demonstrate that if self-protection can transfer the externality to another agent, then noncooperative behavior will lead to overprotection. If self-protection filters or dilutes the externality, then noncooperation leads to underprotection. In addition, overprotection will worsen if an agent with more relative power is allowed a first-mover advantage or if the damage function is elastic and transferability is uncertain. Finally, a reduction in uncertainty about transferability will accentuate overprotection if the damage function is inelastic. Our results suggest that coordination of protection activities among agents will enhance the overall gains from environmental policy in the European Single Internal Market of 1992. Coordination minimizes the costs of environmental protection, thereby reducing the public credibility of its foes.     

Do the Merits Matter More? The Impact of the Private Securities Litigation Reform Act

This article examines the effect of the Private Securities LitigationReform Act of 1995 (PSLRA) on stockholder lawsuits. We explorethe role of restatements, earnings forecasts, and insider tradingin the filing and resolution of lawsuits for a sample of hightechnology firms. Consistent with our predictions, there isa post-PSLRA shift away from litigation based on forward-lookingearnings disclosures. Conversely, there is a significantly greatercorrelation between litigation and both earnings restatementsand abnormal insider selling after the PSLRA. Finally, we finda post-PSLRA increase in the likelihood of settlement for casesinvolving earnings restatements.     

SEPARATING EFFICIENCY AND EQUALITY,AUTOMATION, AND PIKETTY'S THEORY OF INCREASING CAPITAL SHARE

Despite disincentive effects, it is more efficient to tackle inequality by general equality promotion policies, including tax/transfers, than by trying to pursue equality in specific issues or policies. The latter policy also has the same degree of disincentive effects as the general policy but has additional distortive effects. While Piketty' concern with inequality is well taken and his proposal to reduce inequality has merits, his argument on the inevitability of increasing capital share under capitalism and the condition of rate of returns to capital being larger than the rate of growth in incomes (r > g) is not correct. (JEL D3, D6, H)     

Psychometric validation of anti-clot treatment scale and treatment satisfaction questionnaire for medication version II in Japanese patients with atrial fibrillation

Aims: The Anti-Clot Treatment Scale (ACTS) and Treatment Satisfaction Questionnaire for Medication version II (TSQM-II) are validated treatment satisfaction patient-reported outcome (PRO) instruments. The ACTS includes two domains: Burdens and Benefits; the TSQM-II includes four: Effectiveness, Side Effects, Convenience, and Global Satisfaction. Japanese-language versions of the ACTS and TSQM-II have been developed and linguistically validated. This study aimed to assess their psychometric properties in Japanese patients with atrial fibrillation (AF).

Materials and methods: ACTS and TSQM-II data from 534 patients with AF were collected in a Japanese post-marketing surveillance study of a direct oral-anticoagulant, rivaroxaban. Four key psychometric properties, in line with best practice guidelines from the US Food and Drug Administration, were examined using traditional psychometric methods: acceptability, scaling assumptions, reliability (i.e. internal consistency reliability, test-retest reliability), and construct validity (i.e. convergent validity and known groups).

Results: ACTS Burdens and Benefits and TSQM-II Effectiveness, Convenience, and Global Satisfaction scales were found to be acceptable (e.g. item-level missing data at baseline <4%), with all scales having good internal consistency (Cronbach’s alpha > 0.80). test-retest reproducibility intraclass correlation coefficients for the ACTS Burdens and Benefits were 0.59 and 0.65, respectively, and between 0.54–0.61 for the TSQM-II scales. Known-groups validity for the ACTS and TSQM-II was supported by differences in scale scores by positive and negative impact (p?<?0.05). Correlations between the ACTS and TSQM-II (convergent validity) were lower than expected (range r?=?0.09–0.48), but in line with the original ACTS development study.

Limitations: Evaluation of test-retest reproducibility was limited by assessment period, which was longer (3 months) than recommended guidelines (usually up to 2 weeks).

Conclusions: Overall, Japanese versions of ACTS and TSQM-II scales satisfied internal consistency reliability and traditional validity criteria. Our study supports the ACTS and TSQM-II as appropriate PRO instruments to measure satisfaction with anticoagulant treatment in Japanese patients with AF.

Trial registration: NCT01598051, clinicaltrials.gov; registered April 20, 2012.     

Adverse Selection and the Decline in Private Health Insurance Coverage in Australia: 1989–95

The decline in private health insurance coverage over the period 1989–95 is analysed using the ABS National Health Surveys. Individuals' health status and health risk behaviours are found to be significant determinants of their decision to purchase private health insurance. At a point in time, the pool of the insured is very heterogeneous, with a mix of both good and bad health risks. It is found that the decline in insurance coverage over the period 1989–95 coincided with an increase in the degree of 'adverse selection' within the insured population.