"Willingness to Pay for Electric Vehicles and their Attributes"

This article presents a stated preference study of electric vehicle choice using data from a national survey. We used a choice experiment wherein 3029 respondents were asked to choose between their preferred gasoline vehicle and two electric versions of that preferred vehicle. We estimated a latent class random utility model and used the results to estimate the willingness to pay for five electric vehicle attributes: driving range, charging time, fuel cost saving, pollution reduction, and performance. Driving range, fuel cost savings, and charging time led in importance to respondents. Individuals were willing to pay (wtp) from $35 to$75 for a mile of added driving range, with incremental wtp per mile decreasing at higher distances. They were willing to pay from $425 to$3250 per hour reduction in charging time (for a 50 mile charge). Respondents capitalized about 5 years of fuel saving into the purchase price of an electric vehicle. We simulated our model over a range of electric vehicle configurations and found that people with the highest values for electric vehicles were willing to pay a premium above their wtp for a gasoline vehicle that ranged from $6000 to$16,000 for electric vehicles with the most desirable attributes. At the same time, our results suggest that battery cost must drop significantly before electric vehicles will find a mass market without subsidy.Electric Vehicles, Stated Preference, Discrete Choice

"Can Vehicle-to-Grid Revenue Help Electric Vehicles on the Market?"

Vehicle-to-grid (V2G) electric vehicles can return power stored in their batteries back to the power grid and be programmed to do so at times when power prices are high. Since providing this service can lead to payments to owners of vehicles, it effectively reduces the cost of electric vehicles. Using data from a national stated preference survey (n = 3029), this paper presents the first study of the potential consumer demand for V2G electric vehicles. In our choice experiment, 3029 respondents compared their preferred gasoline vehicle with two V2G electric vehicles. The V2G vehicles were described by a set of electric vehicle attributes and V2G contract requirements such as “required plug-in time” and “guaranteed minimum driving range”. The contract requirements specify a contract between drivers and a power aggregator for providing reserve power to the grid. Our findings suggest the V2G concept is mostly likely to help EVs on the market if power aggregators operate on pay-as-you-go-basis or provide consumers with advanced cash payment (upfront discounts on the price of EVs) in exchange for V2G restrictions.electric vehicles, vehicle-to-grid, stated preference, latent-class model

Isolation, via 454 Sequencing, and Characterization of Microsatellites for Vachellia farnesiana (Fabaceae: Mimosoideae)

This work is licensed under a Creative Commons Attribution License (CC-BY-NC-SA) (http://creativecommons.org/licenses/by-nc-sa/4.0).Premise of the study: We isolated 15 polymorphic microsatellite markers from Vachellia farnesiana for use in population genetic studies to determine the native range of the species. Methods and Results: Initially, 454 shotgun sequencing was used to identify and design primers for 68 microsatellite loci. Of these, we trialed 47 loci in the target species, and 42 (89%) amplified a product of expected size. Fifteen of the 47 loci were screened for variation in 21 individuals from the native range of V. farnesiana in southern Mexico and 20 from northwestern Australia. Fourteen loci were polymorphic, with observed heterozygosity ranging from 0.026 to 1.00 (mean = 0.515) and two to 12 alleles per locus (average = 5.2). Cross-amplification was successful in four to 11 loci in three other Vachellia species. Conclusions: The new microsatellite loci will be useful in understanding genetic variation and investigating the role of human-mediated dispersal in the current distribution of V. farnesiana

A Two-Player Game of Life

We present a new extension of Conway's game of life for two players, which we call p2life. P2life allows one of two types of token, black or white, to inhabit a cell, and adds competitive elements into the birth and survival rules of the original game. We solve the mean-field equation for p2life and determine by simulation that the asymptotic density of p2life approaches 0.0362.Comment: 7 pages, 3 figure

Assumptions behind grammatical approaches to code-switching: when the blueprint is a red herring

Many of the so-called ‘grammars’ of code-switching are based on various underlying assumptions, e.g. that informal speech can be adequately or appropriately described in terms of ‘‘grammar’’; that deep, rather than surface, structures are involved in code-switching; that one ‘language’ is the ‘base’ or ‘matrix’; and that constraints derived from existing data are universal and predictive. We question these assumptions on several grounds. First, ‘grammar’ is arguably distinct from the processes driving speech production. Second, the role of grammar is mediated by the variable, poly-idiolectal repertoires of bilingual speakers. Third, in many instances of CS the notion of a ‘base’ system is either irrelevant, or fails to explain the facts. Fourth, sociolinguistic factors frequently override ‘grammatical’ factors, as evidence from the same language pairs in different settings has shown. No principles proposed to date account for all the facts, and it seems unlikely that ‘grammar’, as conventionally conceived, can provide definitive answers. We conclude that rather than seeking universal, predictive grammatical rules, research on CS should focus on the variability of bilingual grammars