Environmental Policy à la Carte: Letting Firms Choose their Regulation

Environmental policy often has to be devised under informational constraints, like uncertainty and asymmetric information. We consider an environmental policy that aims at reducing the welfare losses caused by asymmetric information while being sufficiently simple for implementation. In this policy, firms can choose between being regulated with an emission tax or a permit market. This serves as a screening device; the firms reveal private information by choosing an instrument. We show that such a menu of policy options improves upon conventional environmental policy. Furthermore, the optimal policy is simple and thus easily implementable. The approach is also theoretically interesting, because the simultaneous use of price- and quantity-based instruments induces an asymmetry into the pricesversus- quantities decision compared to Weitzman’s criterion. Especially, there can be an optimal pooling equilibrium where all firms choose the tax, but it is never optimal that all firms participate in permit trading.Environmental Policy, Asymmetric Information, Screening, Uncertainty, Prices-versus-Quantities

Faulhaber's Theorem on Power Sums

We observe that the classical Faulhaber's theorem on sums of odd powers also holds for an arbitrary arithmetic progression, namely, the odd power sums of any arithmetic progression $a+b, a+2b, ..., a+nb$ is a polynomial in $na+n(n+1)b/2$. While this assertion can be deduced from the original Fauhalber's theorem, we give an alternative formula in terms of the Bernoulli polynomials. Moreover, by utilizing the central factorial numbers as in the approach of Knuth, we derive formulas for $r$-fold sums of powers without resorting to the notion of $r$-reflexive functions. We also provide formulas for the $r$-fold alternating sums of powers in terms of Euler polynomials.Comment: 12 pages, revised version, to appear in Discrete Mathematic

Sideband cooling while preserving coherences in the nuclear spin state in group-II-like atoms

We propose a method for laser cooling group-II-like atoms without changing the quantum state of their nuclear spins, thus preserving coherences that are usually destroyed by optical pumping. As group-II-like atoms have a $^1S_0$ closed-shell ground state, nuclear spin and electronic degrees of freedom are decoupled, allowing for independent manipulation. The hyperfine interaction that couples these degrees of freedom in excited states can be suppressed through the application of external magnetic fields. Our protocol employs resolved-sideband cooling on the forbidden clock transition, $^1S_0 \to {}^3P_0$, with quenching via coupling to the rapidly decaying $^1P_1$ state, deep in the Paschen-Back regime. This makes it possible to laser cool neutral atomic qubits without destroying the quantum information stored in their nuclear spins, as shown in two examples, $^{171}$Yb and $^{87}$Sr.Comment: 4 pages, 3 figures v4: minor changes in text, changes in the references, published versio

Evaluating Post-Fire Plantation Restoration in a Mixed Conifer Forest in the Sierra Nevada

Forests in the western United States have experienced a shift from historical disturbance regimes in the past century. Many of these changes were induced by European settlers logging the forests and suppressing fires. In the past, the dry mixed conifer forests of California’s Sierra Nevada mountains experience frequent, low to mixed severity fires. This fire regime helped maintain a heterogeneous landscape comprised of groups of trees and openings. However, due to fire suppression and high grading logging, forest structure has changed; there are less openings and more small, fire-intolerant trees that can carry a fire into the forests crown. The new fire regimes resulting from this change in structure are large, high severity fires that kill a majority of the overstory trees. These novel regimes require novel approaches to regenerate the forest as they are not adapted to large, high severity fires. The United States Forest Service (USFS) will often plant trees after fires to aid with reforestation after large wildfires. A new technique being testing is clustering the trees into groups of two to four, instead of the traditionally evenly spaced plantations. To evaluate these plantations, I compared growth and development in several post fire plantations and natural regenerating stands in the Eldorado National Forest in the north-central Sierra Nevada Mountains. I tested for growth and ecological differences between clustered and evenly spaced plantations, some with pre-commercial thinning (PCT) and some without, as well as comparing them to stands of naturally regenerating trees using mixed effects models. I compared diameter and height growth, along with tree density, shrub size, and understory species diversity. My results suggest that clustered plantations provide a slight facilitative effect when compared to the evenly spaced plantations. I also found high variability in tree stocking, highlighting the intense shrub competition these young plantations face. I also forecasted growth and fire behavior 100 years into the future using the Forest Vegetation Simulation (FVS) and its Fire and Fuels Extension (FFE). In these simulations I tested combinations of different fuels treatments (mastication only, mastication with prescribed burning, and no fuels treatments) with different overstory thinning intensities (residual densities of 370SDI (stand density index), 495SDI, 618SDI (TPH), and no overstory thinning) on stand growth and potential fire behavior using three way analysis of variance. I compared growth and crowning index at the end of the simulation and the simulation age when the flame length, basal area mortality, and fire type reached low severity between fuel treatment, thinning intensity, and original management of stands (plantation with PCT, plantation without PCT, and natural regenerating stands). I found an overall pattern of decreasing crown fire occurrence and fire induced mortality across all simulations due to increasing canopy base height and decreasing canopy bulk density. Mastication with prescribed burning was the most effective treatment for quickly reducing fire behavior by consuming surface fuels, thus drastically lowing flame length. My results highlight the different stressor that post fire plantations experience and how different silvicultrual treatments interact with stand development over time to reduce fire risk. They also demonstrate the importance of treating stands early and the effectiveness of surface fuel treatments

Can Performance of Indigenous Factors Influence Growth and Globalization?

This paper employs a total of thirty four openness factors and indigenous factors to construct two indicators for 62 world economies for the period 1998-2002. While most globalization studies concentrated on openness factors, regression estimates and simulation studies show that sound performance in indigenous factors are crucial to an economy’s growth and globalization. Empirical evidence shows that an optimal performance in indigenous factors can be identified, and that successful globalized economies are equipped with strong performance in their indigenous factors.Globalization, indigenous factors, openness, world economies

Transport of dissolved inorganic carbon from a tidal freshwater marsh to the York River estuary

The cycling of dissolved inorganic carbon (DIC) and the role of tidal marshes in estuarine DIC dynamics were studied in a Virginia tidal freshwater marsh and adjacent estuary. DIC was measured over diurnal cycles in different seasons in a marsh tidal creek and at the junction of the creek with the adjacent Pamunkey River. In the creek, DIC concentrations around high tide were controlled by the same processes affecting whole-estuary DIC gradients. Near low tide, DIC concentrations were 1.5-5-fold enriched relative to high tide concentrations, indicating an input of DIC from the marsh. Similar patterns (although dampened in magnitude) were observed at the creek mouth and indicated that DIC was exported from the marsh. Marsh pore-water DIC concentrations were up to 5 mmol L-1 greater than those in the creek and suggested a significant input of sediment pore water to the creek. A model of tidal marsh DIC export showed that, on a seasonal basis, DIC export rates were influenced by water temperature. The composition of exported DIC averaged 19% dissolved CO2 and 81% HCO3- and CO32-. Although CO2 can be lost to the atmosphere during transit through the estuary DIC in the form of carbonate alkalinity is subject to export from the estuary to the coastal ocean. When extrapolated to an estuarywide scale, the export of marsh-derived DIC to the York River estuary explained a significant portion (47 +/- 23%) of excess DIC production (i.e., DIC in excess of that expected from conservative mixing between seawater and freshwater and equilibrium with the atmosphere) in this system. Therefore, CO2 supersaturation, by itself, does not indicate that an estuary is net heterotrophic

Environmental Policy à la Carte: Letting Firms Choose their Regulation

Environmental policy often has to be devised under informational constraints, like uncertainty and asymmetric information. We consider an environmental policy that aims at reducing the welfare losses caused by asymmetric information while being sufficiently simple for implementation. In this policy, firms can choose between being regulated with an emission tax or a permit market. This serves as a screening device; the firms reveal private information by choosing an instrument. We show that such a menu of policy options improves upon conventional environmental policy. Furthermore, the optimal policy is simple and thus easily implementable. The approach is also theoretically interesting, because the simultaneous use of price- and quantity-based instruments induces an asymmetry into the pricesversus-quantities decision compared to Weitzman’s criterion. Especially, there can be an optimal pooling equilibrium where all firms choose the tax, but it is never optimal that all firms participate in permit trading

Can We Unmask the Phonemic Masking Effect? The Problem of Methodological Divergence

In studying cognition, we infer the presence of mental structures in an idealized setting from performance in various experimental settings. Although experimental settings are believed to tap the mental structure of interest, they also always reflect idiosyncratic task-pecific properties. Indeed, distinct methods often diverge in their outcomes. How can we assess the presence of the mental structure in the idealized setting given divergent outcomes of distinct methods? We illustrate this problem in a specific example concerning the contribution of phonology in reading. Evidence for the role of phonology in the "idealized" reading setting is assessed by different methods. Methods of masked and unmasked display disagree in their outcomes. The contribution of phonology appears robust under masking, but limited under unmasked display. We outline two alternative explanations for the robustness of phonological effects under masking. On one view, phonemic masking effects are a true reflection of early reading stages (Berent & Perfetti, 1995). Conversely, Verstaen et al. (1995) argue (1) that masking overestimates the contribution of phonology and (2) that phonemic masking effects are eliminated by a manipulation that discourages reliance on phonology. We demonstrate that (2) is incorrect, but (1) cannot be resolved empirically