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This paper presents an econometric estimation of the "rebound effect" for household vehicle travel in the United States based on analysis of survey data collected by the Energy Information Administration (EIA) at approximately three-year intervals over a 15-year period. The rebound effect measures the tendency to "take back" potential energy savings from fuel economy improvements as increased travel. Vehicle use models were estimated for one-, two-, three-, four-, and five-vehicle households. The results confirm recent estimates based on national or state-level data: a long-run "take back" of about 20 percent of potential energy savings. Consumer responses to changes in fuel economy or fuel price per gallon appear to be equal and opposite in sign. Recognizing the interdependencies among miles of travel, fuel economy and price is key to obtaining meaningful results. AbstractThis paper reports on an analysis of productivity growth and input trends in six energy intensive sectors of the Indian economy, using growth accounting and econometric methods. The econometric work estimates rates and factor price biases of technological change using a translog production model with an explicit relationship defined for technological change. Estimates of own-price responses indicate that raising energy prices would be an effective carbon abatement policy for India. At the same time, our results suggest that, as with previous findings on the U.S. economy, such policies in India could have negative long-run effects on productivity in these sectors. Inter-input substitution possibilities are relatively weak, so that such policies might have negative short-and medium-term effects on sectoral growth. Our study provides information relevant for the analysis of costs and benefits of carbon abatement policies applied to India and thus contributes to the emerging body of modeling and analysis of global climate policy. AbstractIn China, between 1978 and 1995, energy use per unit of GDP fell by 55 percent. There has been considerable debate about the major factors responsible for this dramatic decline in the energy-output ratio. In this paper we use the two most recent input-output tables to decompose the reduction in energy use into technical change and various types of structural change, including changes in the quantity and composition of imports and exports. In performing our analysis we are forced to deal with a number of problems with the relevant Chinese data and introduce some simple adjustments to improve the consistency of the input-output tables. Our mail conclusion is that between 1987 and 1992, technical change within sectors accounted for most of the fall in the energy-output ratio. Structural change actually increased the use of energy. An increase in the import of some energy-intensive products also contributed to the decline in energy intensity. Pages 93-121Abstract Technological progress, energy use, energy intensity, and carbon mitigation are tightly intertwined concepts within the worldwide climate change debate. The s...

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By reducing the fuel costs of travel, motor vehicle efficiency improvements tend to increase the demand for travel, thereby offsetting some of the energy-saving benefit of the efficiency improvement and creating a “rebound” effect. The key factor is the elasticity of vehicle travel with respect to fuel cost per mile. Past studies offer a wide range of estimates depending on model formulation and time period, with more recent analyses indicating that travel is insensitive to fuel costs and efficiency. This paper analyzes U.S. light-duty vehicle miles travelled from 1966-89, examining a variety of statistical issues that bear on the size of the “rebound” effect, including error structure, functional form, and possible lagged effects. The results consistently confirm that the “rebound” effect has been quite small, about 5-15%, or less; and that short-run (one year) adjustments accounted for essentially all of the change in travel due to fuel price and fuel economy changes. The findings imply that the energy savings of technical fuel economy improvements to cars and light trucks will be only slightly reduced by increased vehicle travel. They also imply that gasoline taxes would need to be very large in order to stimulate significant reductions in travel.

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Medial displacement osteotomy of the calcaneous is commonly performed for stage II posterior tibial tendon insufficiency in an effort to improve the valgus deformity of the hindfoot. We performed an anatomic study examining the medial neurovascular anatomy and its relation to the osteotomy in an attempt to determine which structures may be at risk during the procedure. Calcaneal osteotomies were performed through a lateral approach on 22 fresh-frozen cadaver below-knee specimens. Dissection was then performed medially to identify the Medial Plantar Nerve (MPN), the Lateral Plantar Nerve (LPN), the Posterior Tibial Artery (PTA), and their respective branches. Measurements determined either 1) where the structure crossed the osteotomy or 2) if the structure did not cross, the closest perpendicular distance from the osteotomy and at which point along its length this occurred. Perpendicular distances were recorded in millimeters and position along the osteotomy as a percentage of the total length from the posterosuperior aspect. An average of four neurovascular structures crossed each osteotomy site (range 2 to 6), most of which were branches of the LPN or the PTA. The MPN did not cross in any of the specimens studied, the LPN crossed in one specimen, and the PTA crossed in two specimens. The MPN distributed no crossing branches. The calcaneal sensory branch of the LPN was identified and crossed in 86% of the cadavers at 19% (+/- 15%) along the osteotomy length. A more distal second branch of the LPN (Baxter's nerve) was identified and crossed in 95% of the specimens at 61% (+/ 20%) along the osteotomy length. A third crossing branch existed in one specimen. Each PTA distributed from zero to three branches which variably crossed the osteotomy at a point from 2% to 100% along its length. The PTA bifurcated in 77% of the specimens at 49% (+/- 9%) along the osteotomy length. A consistent finding in every specimen was the presence of two veins accompanying the PTA with one on either side. A number of medial neurovascular structures may be at risk when perfoming a calcaneal osteotomy through a lateral approach. A minimum of two structures crossed the osteotomy site at variable positions in this study, although most of these structures represented branches off of the LPN or the PTA, with the LPN and the PTA themselves crossing only infrequently. The authors recommend that the completion of the osteotomy through the medial calcaneal cortex be performed in a carefully controlled manner to reduce the risk of post-operative complications including pain, numbness, and hematoma formation.