Constructing Krinsky and Robb Confidence Interval for Mean and Median WTP Using Stata

The ultimate goal of most non-market valuation studies is to obtain welfare measures i.e. mean and/or median willingness to pay (WTP) and confidence intervals. While the delta (nlcom) and bootstrap (bs) methods can be used for constructing such confidence intervals in Stata, they are not recommended because WTP measures are non-linear functions of random parameters (Creel and Loomis, 1991). The best and widely used approach, which is not available in Stata, consists in simulating the confidence intervals using the Krinsky and Robb procedure (Haab and McConnell, 2002). Hole (2007) has recently introduced a useful command, wtp, which implements the Krinsky and Robb procedure in Stata, but does not feature mean and median WTP estimates and their confidence intervals. I present a Stata command, wtpcikr, which computes mean and median WTP, confidence intervals using the Krinsky and Robb procedure, achieved significance level (ASL) for testing the null hypothesis that WTP equals zero, and a relative efficiency measure (Loomis and Ekstrand, 1998). The command supports both linear and exponential contingent valuation models estimated with or without covariates using the Stata commands probit, logit, biprobit, and xtprobit. I will illustrate the use of wtpcikr by replicating empirical results in Haab and McConnell (2002).

Demand for Electricity Connection in Rural Areas : The Case of Kenya

A modern form of energy, in particular electricity for household use, is an important vehicle in alleviating poverty in developing countries. However, access and costs of connecting to this service for most poor in these countries is inconceivable. Policies promoting electricity connection in rural areas are known to be beneficial in improving the socio-economic and health well-being for households. This paper examines willingness to pay (WTP) for rural electrification connection in Kisumu district, Kenya, using the contingent valuation method (CVM). A nonparametric and a parametric model are employed to estimate WTP values for two electricity products: grid electricity (GE) and photovoltaic (PV) electricity. The results indicate that respondents are willing to pay more for GE services than PV and households favoured monthly connection payments over a lump sum amount. Some of the policies suggested in this paper include: subsidizing the connection costs for both sources of electricity, adjusting the payment periods, and restructuring the market ownership of providing rural electricity services.double bounded; contingent valuation; electricity connection; rural; willingness to pay (wtp)

Poverty rate and government income transfers: A spatial simultaneous equations approach

The poverty rate and income transfer are clearly correlated. However, not much research has attempted to determine the causal linkage between the two. Previous research has primarily focused on the poverty-reducing impact of income transfer. In this paper, we apply a simultaneous equation system of spatial regressions to uncover the spatial pattern of the relationship between the poverty rate and income transfer, using a sample of 3,001 U.S. counties. The results are in line with theoretical expectations; they provide evidence of a significant simultaneity effect between the poverty rate and income transfer. Our findings also confirm the presence of significant spatial autocorrelation. Contrary to previous studies, we find that more generous counties tend to do a better job of reducing poverty and that counties with more poor tend to be less generous, creating incentive for the poor to participate in the labor force. Furthermore, counties located in devolution states perform better in both poverty reduction and income transfer. These findings are missing from extant literature that focuses only on the poverty-reducing impact of welfare payments.endogeneity, income transfer, Poverty, SHAC, spatial econometrics,

Using stated preferences to estimate the environmental benefits of using biodiesel fuel in diesel engines

Using biodiesel fuel to reduce emissions from diesel engines is an area of increasing interest. Many environmental benefits associated with biodiesel are not traded in markets and their estimation requires economic valuation methods applied to non-market goods and services. This paper presents the results of a contingent valuation survey conducted in 2006 in two Ohio regions to estimate willingness to pay for air pollution reduction arising from using biodiesel fuel in diesel engines. The double bounded parametric formulation was used to estimate mean WTP ranging from $157 to$457. These results yield estimated aggregate benefits ranging from $123 to$429 million and can be used as a starting point for cost-benefit analysis.Biodiesel, diesel, air pollution, environmental benefits, contingent valuation, willingness to pay, double bounded model, Environmental Economics and Policy, Resource /Energy Economics and Policy, I18, L91, Q42, Q51, Q53,

Assessing Ohio's Biomass Resources for Energy Potential Using GIS

This recently completed AEDE study funded by Ohio DOD involves a geo-referenced inventory by county of Ohio biomass resources for energy. Categories include forest and crop residues, livestock manure, municipal solid waste and food processing waste. This is an update and expansion of an earlier (1982) inventory of biomass by Hitzhusen et al. It also disaggregates and expands a study by Walsh et al. in 2000 which ranked Ohio 11th among the 50 states in total biomass availability. By estimating and geo-referencing the sustainable quantities of various categories of biomass for energy by county, it is possible to identify the spatial concentrations of various biomass renewable energy feedstocks that may be economically viable for various processes for conversion. These conversion processes in turn have implications for environmental improvement and reduced dependence on foreign oil imports. A better understanding of the technical and economic pros and cons of the most promising conversion processes will be required along with further data collection and refinements of this inventory (particularly the food processing waste subset) before detailed policy recommendations can be made. However, this study is hopefully a good start toward that goal and should provide direction and focus for future analysis and recommendations for a more renewable and sustainable energy and environmental future for Ohio.Availability, Biomass energy, Crop residues, Livestock manure, Wood wastes, Municipal solid wastes.

Willingness to Pay for Biodiesel in Diesel Engines: A Stochastic Double Bounded Contingent Valuation Survey

The double bounded dichotomous choice format has been proven to improve efficiency in contingent valuation models. However, this format has been criticized due to lack of behavioral and statistical consistencies between the first and the second responses. In this study a split sampling methodology was used to determine whether allowing respondents to express uncertainty in the follow-up question would alleviate such inconsistencies. Results indicate that allowing respondents to express uncertainty in the follow-up question was effective at reducing both types of inconsistencies while efficiency gain is maintained.Biodiesel, diesel, environmental benefits, contingent valuation, willingness to pay, double bounded model, and statistical and behavioral inconsistencies, Demand and Price Analysis, Resource /Energy Economics and Policy, I18, L91, Q42, Q51, Q53,

Dealing with Internal Inconsistency in Double-Bounded Dichotomous Choice: An Application to Community-Based Health Insurance

Contingent valuation method is commonly used in the field of health economics in an attempt to help policy maker in taking decisions. The use of the double-bounded dichotomous choice format results in a substantial gain in statistical efficiency over the single bounded dichotomous choice format. Yet, this efficiency gain comes at the cost of biasness known as internal inconsistency. This paper aims at reducing this internal inconsistency in double-bounded dichotomous choice by using the certainty calibration technique in a community-based health insurance study. Findings confirm the internal inconsistency between the initial and the follow-up responses and the statistical efficiency gains of the double-bounded dichotomous choice over the single-bounded dichotomous choice. Furthermore, the use of certainty calibration reduces this internal inconsistent pattern in responses and still maintains efficiency gain. We further discuss the policy implications.Contingent valuation; internal inconsistency; certainty calibration; community-based health insurance

Development of a gel content analysis protocol for ultra high molecular weight polyethylene

A modified procedure based upon ASTM (D 2765 - 90) to determine the gel content of crosslinked polyethylene plastics was developed. The new procedure was applied to ram extruded Ultra High Molecular Weight (UHMWPE) implant components processed under different manufacturing conditions. This new evaluation tool provides consistent results with greater accuracy and consistency compared to the American Society for the Testing of Materials (ASTM) method. Using the same tool, several relationships between the UHMWPE processing conditions and gel content were established. The amount of gel content is related to the crosslinked material. It has been shown that the more crosslinking present in a material, the befter its resistance is to wear. This new development is very useful in the comparison of various UHMWPE raw materials and the development of new UHMWPE materials

Search for lepton flavour violation in the eμ continuum with the ATLAS detector in √s = 7 TeV pp collisions at the LHC

This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark (t) in the e^± μ^∓ continuum using 2.1 fb^(−1) of data collected by the ATLAS detector in √s = 7 TeV pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 % C.L. are calculated as a function of the scalar top mass (mt). The upper limits on the production cross section for pp → eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for m_t=95 GeV to 30 fb for m_t=1000 GeV

Optimal use of Charge Information for the HL-LHC Pixel Detector Readout

The pixel detectors for the High Luminosity upgrades of the ATLAS and CMS detectors will preserve digitized charge information in spite of extremely high hit rates. Both circuit physical size and output bandwidth will limit the number of bits to which charge can be digitized and stored. We therefore study the effect of the number of bits used for digitization and storage on single and multi-particle cluster resolution, efficiency, classification, and particle identification. We show how performance degrades as fewer bits are used to digitize and to store charge. We find that with limited charge information (4 bits), one can achieve near optimal performance on a variety of tasks.Comment: 27 pages, 20 figure