Avoiding Accountability: How Charter Operators Evade Ohio's Automatic Closure Law

Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. The law has been showcased by the National Association of Charter School Authorizers (NACSA) in its "One Million Lives" campaign, which calls for tougher state laws to close failing charter schools.The widespread attention and support of the NACSA campaign has pushed Ohio's closure law into the spotlight as a model of accountability for low-performing charter schools. However, The Plain Dealer's editorial board, in a commentary on NACSA's praise of Ohio's charter school accountability standards, pointed out what NACSA did not: Ohio's charter school laws, while they may have stronger mandates for closure than those of other states, are still replete with loopholes. Since the charter-closure law went into effect in 2008, 20 schools across the state have met closure criteria, and all are currently listed as closed by the Ohio Department of Education (ODE). But an investigation of the schools by Policy Matters revealed that eight schools -- and the management companies that run them -- have found ways to skirt the closure law and remain open, severely undermining the law's effectiveness and highlighting the lax accountability that prevails in Ohio's charter sector. For-profit managers -- the Leona Group, Mosaica Education and White Hat Management -- operate six of the reopened schools

Modeling of transpiration reduction in van Genuchten-Mualem type soils

We derive an analytic expression for the matric flux potential (M) for van Genuchten-Mualem (VGM) type soils which can also be written in terms of a converging infinite series. Considering the first four terms of this series, the accuracy of the approximation was verified by comparing it to values of M estimated by numerical finite difference integration. Using values of the parameters for three soils from different texture classes, the proposed four-term approximation showed an almost perfect match with the numerical solution, except for effective saturations higher than 0.9. Including more terms reduced the discrepancy but also increased the complexity of the equation. The four-term equation can be used for most applications. Cases with special interest in nearly saturated soils should include more terms from the infinite series. A transpiration reduction function for use with the VGM equations is derived by combining the derived expression for M with a root water extraction model. The shape of the resulting reduction function and its dependency on the derivative of the soil hydraulic diffusivity D with respect to the soil water content theta is discussed. Positive and negative values of dD/d theta yield concave and convex or S-shaped reduction functions, respectively. On the basis of three data sets, the hydraulic properties of virtually all soils yield concave reduction curves. Such curves based solely on soil hydraulic properties do not account for the complex interactions between shoot growth, root growth, and water availabilit

STRATEGIC DELEGATION IN OLIGOPOLY: THE MARKET SHARE CASE

In this paper, we consider a two-stage (sequential) game as introduced by Vickers (1985),Fershtman (1985), Fershtman and Judd (1987) and Sklivas (1987). This game models the situation where the owners of competing firms manipulate their managers'' incentive contracts for strategic reasons. Instead of the sales volume as part of these contracts, we introduce market share, besides profit, as a natural part of managers'' incentives. Then we compare the results with those obtained for combinations of profits and sales volume, as well as for the classical Cournot model. Concerning an {\eightit n}-firm oligopoly, and compared to the sales-delegation case, it appears that owners put more emphasis on managerial profit-maximizing behavior, indicated by smaller weights attributed to market share in managerial incentive contracts. Social welfare corresponding to the market share-delegation case almost equals welfare associated with the sales-delegation case. However, its components differ.The case of market share-delegation leads to a higher profitability of incumbent rivals and to a lower consumer surplus, in comparison to the sales-delegation case. One may state that the owner''s strategic use of market share as a managerial incentive leads to a (partial) shift of benefits from consumers to producers.mathematical economics;

Disease burden of varicella versus other vaccine-preventable diseases before introduction of vaccination into the National Immunisation Programme in the Netherlands

IntroductionEstimating burden of disease (BoD) is an essential first step in the decision-making process on introducing new vaccines into national immunisation programmes (NIPs). For varicella, a common vaccine-preventable disease, BoD in the Netherlands was unknown.AimTo assess national varicella BoD and compare it to BoD of other vaccine-preventable diseases before their introduction in the NIP.MethodsIn this health estimates reporting study, BoD was expressed in disability-adjusted life years (DALYs) using methodology from the Burden of Communicable Diseases in Europe (BCoDE)-project. As no parameters/disease model for varicella (including herpes zoster) were available in the BCoDE toolkit, incidence, disease progression model and parameters were derived from seroprevalence, healthcare registries and published data. For most other diseases, BoD was estimated with existing BCoDE-parameters, adapted to the Netherlands if needed.ResultsIn 2017, the estimated BoD of varicella in the Netherlands was 1,800 (95% uncertainty interval (UI): 1,800-1,900) DALYs. Herpes zoster mainly contributed to this BoD (1,600 DALYs; 91%), which was generally lower than the BoD of most current NIP diseases in the year before their introduction into the NIP. However, BoD for varicella was higher than for rotavirus gastroenteritis (1,100; 95%UI: 440-2,200 DALYs) and meningococcal B disease (620; 95%UI: 490-770 DALYs), two other potential NIP candidates.ConclusionsWhen considering the introduction of a new vaccine in the NIP, BoD is usually estimated in isolation. The current approach assesses BoD in relation to other vaccine-preventable diseases' BoD, which may help national advisory committees on immunisation and policymakers to set vaccination priorities

Anaerobic membrane bioreactors: Are membranes really necessary?

Membranes themselves represent a significant cost for the full scale application of anaerobic membrane bioreactors (AnMBR). The possibility of operating an AnMBR with a self-forming dynamic membrane generated by the substances present in the reactor liquor would translate into an important saving. A self-forming dynamic membrane only requires a support material over which a cake layer is formed, which determines the rejection properties of the system. The present research studies the application of self-forming dynamic membranes in AnMBRs. An AnMBR was operated under thermophilic and mesophilic conditions, using woven and non woven materials as support for the dynamic membranes. Results showed that the formation of a cake layer over the support materials enables the retention of more than 99% of the solids present in the reactor. However, only low levels of flux were achieved, up to 3 L/m2 x h, and reactor operation was unstable, with sudden increases in filtration resistance, due to excessive cake layer formation. Further fine-tuning of the proposed technology involves looking for conditions that can control effectively cake layer formatio