substitution effects
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Energy intensive industries (EIIs) in China are predominantly reliant on fossil fuels. Consequently, such high fossil fuel dependency has amplified carbon emission levels and blocked the low-carbon transition. It is inappropriate to discuss the solution of the dependency before investigating fossil-fuel price distortion and its impact on the industrial energy consumption. Therefore, this paper built a dynamic trans-log cost function model based on provincial panel data of China’s Ells between 2004 and 2016, to investigate inter-fuel substitution effects caused by own price elasticities and cross price elasticities, and analyzed the impact of fossil-fuel price distortions on low-carbon transition. The level of price distortions in coal, gasoline and diesel was evaluated, based on which the CO2 mitigation potentials in China’s EIIs were estimated. Results show that: 1) in each EII sector, the own price elasticities of all fuels were negative while the cross price elasticities among coal, oil and electricity were positive, suggesting substitution effect exists; 2) the average level of price distortions in coal, gasoline and diesel is 7.48, 11.1 and 32.19%, respectively, which means the prices of coal tend to be more market- oriented than the other two fuels; 3) removing coal price distortions can potentially reduce CO2 emissions in China’s EIIs by 905.78 million tons, while the effects of removing oil price distortions were uncertain, unless the substitution of coal for oil was restrained. Therefore, there is still much room for improvement in China’s fossil-fuel market reform. Possible policies are required to improve the production in EIIs and the low-carbon transition by adopting cleaner energy resources to substitute fossil-fuels.

Abstract Background The number of children and adolescents with obesity has increased worldwide. Some studies have found an increase in the intake of n-3 long-chain polyunsaturated fatty acid (LCPUFA) to be beneficial for weight and obesity status. The objectives of this study were to examine if intake of trans-fatty acids (TFA) and n-3 LCPUFA at school start was associated with weight and body fat development in the following 3 and 7 years, and if substituting other fats for n-3 LCPUFA in regression models influenced weight and body fat development. Methods A total of 285 children (boys:130, girls:155) were included in this study. Weight, height and skinfold thickness (SF) of children were measured at age 6, 9 and 13 years by trained research personnel. Multivariate linear regression models were used to investigate the associations between n-3 LCPUFA or TFA intake and subsequent changes in body mass index (BMI) or SF. To investigate substitution effects, we constructed regression models including information on n-3 LCPUFA and all other energy given components of the diet, except for the nutrient to be substituted (all other fats and specific subgroups; saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and other polyunsaturated fatty acids (PUFAs)). Results No significant associations were observed between intake of TFA or n-3 LCPUFA and changes in BMI and SF. Also, results from regression analysis showed substituting other fats for n-3 LCPUFA did not associate with BMI or SF development. Conclusion The lack of associations between n-3 LCPUFA and TFA and adiposity suggests that fat composition in the diet does not play a major role in obesity development among school-aged children.

For complexes involving aromatic species, substitution effects can influence the preferred geometry.

AbstractUsing price quotes and invoices for thousands of full-text databases and single-journal subscriptions, this study confirms that for a typical master’s university, the journals acquired through commercial publishers’ databases cost substantially less than those acquired through the databases of scholarly societies, universities, and other nonprofits. Moreover, the lower prices of commercial publishers’ journals cannot be readily attributed to publisher size (number of journals published) or to any of several other explanatory variables. There is a weak, direct association between publisher size and price among the for-profit journals but a stronger, inverse relationship between publisher size and price among the nonprofit journals. These findings, along with the results of previous research, suggest that resource providers may have incentives to keep prices low due to the collection development strategies adopted by many teaching-oriented colleges and universities. If the library’s goal is to hold a sufficient number of high-quality journals rather than to provide immediate access to every wanted journal, particular journals and databases may be regarded as substitutes even when each product provides unique content. Many U.S. bachelor’s and master’s institutions have goals different from those of the major research universities, and commercial publishers (along with some of the larger nonprofits) seem to recognize this when setting and negotiating prices.

Abstract:Objective: Examine how socio-economic status (SES) and health outcomes affect binge-drinking demand using a novel approach integrating population health with consumer expenditure data.Design, Setting, and Participants: The study design uses a structural equation model to uncover the association between binge-drinking and SES. I use the 2016 wave of two annually conducted national population surveys in this research: the Behavioral Risk Factor Surveillance (BRFS) and the Consumer Expenditure Survey (CEX), to examine the correlates of binge-drinking. The combined aggregated data integrates alcohol expenditure shares and state-level alcohol prices from the CEX with the BRFS data. The BRFS data partially identifies the at-risk for binge-drinking respondents for our analysis.Main outcome and exposures: Alcohol consumption > 0 in 30 days and binge-drinking is positive (per occasion drinks > 5 male or > 4 female).Results: The binge-drinking prevalence in the BRFS sample, with 457,202 respondents 18 and older, is 17.0% points. Associations with binge-drinking are the same for the poorest and richest income quartiles. Age has the strongest variation. Compared to those over 65, ages 18 ¬– 21 participated in binge-drinking more, and ages 30 – 64 participated much less. Contrasted with those out-of-the-labor-force, the employed participated in binge-drinking more by 3.5% [95% CI, 2.3%, 5.0%] and those unable to work by 4.5% [95% CI, 3.3%, 6.0%] less. The estimated structural models show that, conditional on binge-drinking in a 30-day period, those with high school education or more increased binge-drinking intensity by 3.4% [95% CI, 1.3%, 5.5%] to 5.0% [95% CI, 2.8%, 7.2%] .As people age, expenditure shares on alcohol and cigarettes decrease but healthcare expenditure shares increase proportionately. Furthermore, compared to those without any chronic health conditions alcohol shares decrease by 0.5 [95% CI, -0.57, -0.43] times as number of health conditions increase; this decrease in alcohol consumptions is substituted by increased expenditure shares on food and health care proportionately. Compared to those without high school education alcohol shares decrease with education 0.13 [95% CI, 0.05, 0.23] times for high school graduates and 0.10 [95% CI, 0.3 0.21] times for those with college degrees.Conclusion and Relevance: Bridging the gap between population health and consumer data reveals income effects of binge-drinking are best captured using BRFS because we can characterize a population at risk for binge drinking. CEX best captures income shares and substitution effects between alcohol, smoking, health and food. Alcohol consumption is associated with employment and engaging in other risky behaviors. While this analysis was conducted using 2016 BRFS data the results are generalizable to 2019 BRFS data and extendable to COVID-19 era. Preliminary indications are that alcohol consumption have gone up during COVID-19 thus mobilizing resources to reduce binge-drinking is welfare enhancing. A plausible policy implication from this study is to advertise safe drinking on all alcoholic beverages and provide alcohol-specific education on self-and-other harm.

Abstract We perform path-integral molecular dynamics (PIMD) and classical MD simulations of H2O and D2O using the q-TIP4P/F water model over a wide range of temperatures and pressures. The density ρ(T), isothermal compressibility κT(T), and self-diffusion coefficients D(T) of H2O and D2O are in excellent agreement with available experimental data; the isobaric heat capacity CP(T) obtained from PIMD and MD simulations agree qualitatively well with the experiments. Some of these thermodynamic properties exhibit anomalous maxima upon isobaric cooling, consistent with recent experiments and with the possibility that H2O and D2O exhibit a liquid-liquid critical point (LLCP) at low temperatures and positive pressures. The data from PIMD/MD for H2O and D2O can be fitted remarkably well using the Two-State-Equation-of-State (TSEOS). Using the TSEOS, we estimate that the LLCP for q-TIP4P/F H2O, from PIMD simulations, is located at Pc = 167±9 MPa, Tc = 159±6 K, and ρc = 1.02±0.01 g/cm3. Isotope substitution effects are important; the LLCP location in q-TIP4P/F D2O is estimated to be Pc = 176 ± 4 MPa, Tc = 177 ± 2 K, and ρc = 1.13±0.01 g/cm3. Interestingly, for the water model studied, differences in the LLCP location from PIMD and MD simulations suggest that nuclear quantum effects (i.e., atoms delocalization) play an important role in the thermodynamics of water around the LLCP (from the MD simulations of q-TIP4P/F water, Pc = 203 ± 4 MPa, Tc = 175 ± 2 K, and ρc = 1.03 ± 0.01 g/cm3). Overall, our results strongly support the LLPT scenario to explain water anomalous behavior, independently of the fundamental differences between classical MD and PIMD techniques. The reported values of Tc for D2O and, particularly, H2O suggest that improved water models are needed for the study of supercooled water.

Problem definition: This paper studies pricing and assortment management for cross-category products, a common practice in brick-and-mortar retailing and e-tailing. Academic/practical relevance: We investigate the complementarity effects between the main products and the secondary products, in addition to the substitution effects for products in the same category. Methodology: In this paper, we develop a multistage sequential choice model, under which a consumer first chooses a main product and then selects a secondary product. The new model can alleviate the restriction of the independence of irrelevant alternatives property and allows more flexible substitution patterns and also takes into account complementarity effects. Results: We characterize the impact of the magnitude of complementarity effects on pricing and assortment management. For the problems that are hard to solve optimally, we propose simple heuristics and establish performance guarantee. In addition, we develop easy-to-implement estimation algorithms to calibrate the proposed sequential choice model by using sales data. Managerial implications: We show that ignoring or mis-specifying complementarity effects may lead to substantial losses. The methodologies on modeling, optimization, and estimation have potential to make an impact on cross-category retailing management.

Many retailers are reducing store footprint and downsizing their assortments accordingly to improve store productivity. Some of the revenue for items removed from the assortment may be recouped by substitution, but also some of the revenue for items kept in the assortment may be lost due to basket abandonment. For a practical setting where baskets may contain any subset of items from thousands of products, estimating both substitution and basket effects is a challenge. To address this, we develop a demand model that combines a multinomial logit (MNL) model to estimate substitution within a subcategory and a purchase-incidence model to estimate basket retention. Using transaction and product availability data from 12 stores of an office supplies retail chain that were dramatically downsized from large- to small-format stores, we show that (i) storewide basket effects are substantial (our model with basket effects predicts out-of-sample transactions with mean absolute percent error (MAPE) of only 7% compared with 22% for a model with only substitution effects), (ii) poor service level can significantly exacerbate lost profit due to abandoned baskets at these stores, and (iii) consideration of the basket effect in assortment selection for the small stores can significantly improve basket retention and increase profits (by up to 16%) at these stores. This paper was accepted by Vishal Gaur, operations management.