bank acquisitions and ownership structure theory and evidence abstract in this paper we both theoretically and empirically consider the joint nature of two ownermanager conflict resolution mechanisms insider shareholdings and shareholder concentration we find evidence of a significant entrenchment effect for high low firms moreover bidder returns are found to be positive for high high firms only we utilize a switching of regression regimes model to solve for critical values of and that subdivide the universe of acquiring firms into separate and distinct ownership structure regimes i e that define high vs low levels of or

clearing and pricing for coordinated gas and electricity day ahead markets considering wind power uncertainty natural gas and electricity systems are becoming increasingly strongly coupled gas fired units gfus are replacing retired coal plants and the power systems are more dependent on the flexibilities provided by gfus the gfus power generation capability relies on the availability of gas resources which is jointly determined by the capacity of gas suppliers and pipeline networks however the gas and electricity markets are operated separately consequently the gfus are forced to represent the entire power system to bid on the gas market they must make forecasts regarding future gas consumption and bear the risk of improper contracts or being unable to meet generation schedules due to occasional insufficient gas supply when facing larger shares of renewable energies and more frequent gas network congestions the current market framework is particularly unreliable and inefficient as well as economically unfriendly to the investors of the gfu assets in this paper we try to develop a framework that can combine the two markets by properly pricing the scarce resources e g gas transmission capacity the joint market can help us to allocate the resources more efficiently while satisfying the demands moreover a more forward looking day ahead market clearing framework is presented by considering the uncertainty brought by renewable energies the formulation and algorithm of the proposed joint market model will be presented as are some case studies

delegated portfolio management abstract a problem of screening agents with privately known forecasting abilities and reservation utilities and then eliciting truthful information from these agents once they are employed is considered for the case of risk averse agents and large principals an approximately optimal solution is constructively characterized under the assumption that payoffs are normally distributed a significant extension of the definnetti savage probability elicitation result is developed under this extension knowledge of agent preferences is not required when the underlying conditional distributions are symmetric and this fact is exploited to solve the screening problem in a mean variance formulation

market clearing with stochastic security part i formulation the first of this two paper series formulates a stochastic security constrained multi period electricity market clearing problem with unit commitment the stochastic security criterion accounts for a pre selected set of random generator and line outages with known historical failure rates and involuntary load shedding as optimization variables unlike the classical deterministic reserve constrained unit commitment here the reserve services are determined by economically penalizing the operation of the market by the expected load not served the proposed formulation is a stochastic programming problem that optimizes concurrently with the pre contingency social welfare the expected operating costs associated with the deployment of the reserves following the contingencies this stochastic programming formulation is solved in the second companion paper using mixed integer linear programming methods two cases are presented a small transmission constrained three bus network scheduled over a horizon of four hours and the ieee reliability test system scheduled over 24 h the impact on the resulting generation and reserve schedules of transmission constraints and generation ramp limits of demand side reserve of the value of load not served and of the constitution of the pre selected set of contingencies are assessed

equilibrium of interdependent gas and electricity markets with marginal price based bilateral energy trading the increasing interdependencies between natural gas systems and power systems create new business opportunities in coupled energy distribution markets this paper studies the marginal price based bilateral energy trading on the equilibrium of coupled natural gas and electricity distribution markets convex relaxation is employed to solve a multiperiod optimal power flow problem which is used to clear the electricity market a successive second order cone programming approach is utilized to solve a multiperiod optimal gas flow problem which is used to clear the gas market in addition the line pack effect in the gas network is considered which can offer storage capacity and provide extra operation flexibility for both networks in both problems locational marginal energy prices are recovered from the lagrangian multipliers associated with nodal balancing equations furthermore a best response decomposition algorithm is developed to identify the equilibrium of the coupled energy markets with bilateral gas and electricity trading which leverages the computational superiority of socps cases studies on two test systems validate the proposed methodology

a stochastic electricity market clearing formulation with consistent pricing properties we argue that deterministic market clearing formulations introduce arbitrary distortions between day ahead and expected real time prices that bias economic incentives we extend and analyze a previously proposed stochastic clearing formulation in which the social surplus function induces penalties between day ahead and real time quantities we prove that the formulation yields price bounded price distortions and we show that adding a similar penalty term to transmission flows and phase angles ensures boundedness throughout the network we prove that when the price distortions are zero day ahead quantities equal a quantile of their real time counterparts the undesired effects of price distortions suggest that stochastic settings provide significant benefits over deterministic ones that go beyond social surplus improvements we propose additional metrics to evaluate these benefits

health and work in the family evidence from spouses cancer diagnoses abstract using canadian administrative data from multiple sources we provide the first nationally representative estimates for the effect of spouses cancer diagnoses on individuals employment and earnings and on family income our identification strategy exploits unexpected health shocks and combines matching with individual fixed effects in a generalized difference in differences framework to control for observable and unobservable heterogeneity while the effect of spousal health shocks on labor supply is theoretically ambiguous we find strong evidence for a decline in employment and earnings of individuals whose spouses are diagnosed with cancer we interpret this result as individuals reducing their labor supply to provide care to their sick spouses and to enjoy joint leisure family income substantially declines after spouses cancer diagnoses suggesting that the financial consequences of such health shocks are considerable

interdependency of natural gas network and power system security this paper proposes an integrated model for assessing the impact of interdependency of electricity and natural gas networks on power system security the integrated model incorporates the natural gas network constraints into the optimal solution of security constrained unit commitment the natural gas network is modeled by daily and hourly limits on pipelines sub areas plants and generating units the application of fuel diversity e g generating units with fuel switching capability is presented as an effective peak shaving strategy for natural gas demand which could hedge price volatilities of natural gas and electric power the proposed model can be used by a vertically integrated utility for the commitment and dispatch of generating units and the allocation of natural gas for the next day utilization the proposed model can also be used for measuring the security of social services by modeling the interdependency of natural gas and electric power system infrastructures if the proposed model is used by gencos gas constraints will be submitted to electricity markets as energy constraints illustrative examples show the impact of natural gas supply infrastructure on the economic operation of a vertically integrated utility the examples also discuss the impact of generating units with fuel switching capability on the power system security when the supply of natural gas is limited

the earnings of informal carers wage differentials and opportunity costs a substantial proportion of working age individuals in britain are looking after sick disabled or elderly people often combining their work and caring responsibilities previous research has shown that informal care is linked with substantial opportunity costs for the individual due to forgone wages as a result of non labour market participation in this paper we show that informal carers exhibit further disadvantages even when participating using the british household panel study bhps we decompose wage differentials and show that carers can expect lower returns for a given set of characteristics with this wage penalty varying along the pay distribution and by gender furthermore opportunity costs from forgone wages and wage penalties are estimated and found to be substantial

pricing electricity through a stochastic non convex market clearing model this paper proposes a pricing scheme for the day ahead market in power systems with a large percentage of renewable stochastic production to clear the day ahead market instead of a simplistic deterministic model we use a two stage stochastic programming model that embodies a prognosis of future operating conditions non convexities due to start up costs and the on off status of generators and their minimum power outputs are properly taken into account our goal is to obtain uniform day ahead clearing prices that deviate in the least possible manner from marginal prices and that allow producers to recover their costs without uplifts the proposed methodology is illustrated using a simple example and a realistic case study

gas electricity coordination in competitive markets under renewable energy uncertainty as climate concerns low natural gas prices and renewable technologies increase the electric power sector s dependence on natural gas fired power plants operational and investment models for gas and electric power systems will need to incorporate the interdependencies between these two systems to accurately capture the impacts of one on the other currently few hybrid gas electricity models exist this paper reviews the state of the art for hybrid gas electricity models and presents a new model and case study to illustrate a few potential coupling effects between gas and electric power systems specifically the proposed model analyzes the optimal operation of gas fired power plants in a competitive electricity market taking into consideration gas purchases gas capacity contracting and residual demand uncertainty for the generation company due to renewable energy sources

incentives and supervision in hierarchies abstract this paper describes a simple and therefore limited model for incentives design under imperfect hierarchical supervision in order to explain certain empirical evidence on the relative importance of bonuses and salaries for the compensation of managers some theoretical implications are also derived from the model first we find that improvements in the activity of supervision do not always imply higher salaries and less incentives as is implicitly recognized in certain agency models secondly the introduction of incentives in a hierarchy which is performing imperfect supervision may not be sufficient to remove the limits to the firm s size which is attributed to this imperfection

pricing flexible natural gas supply contracts under uncertainty in hydrothermal markets the worldwide development of the natural gas industry resulted in an integration process between electrical and gas sectors in several countries in brazil this process has been taking place in a consistent manner especially on account of the increase in gas consumption for industrial use and of the installation of thermoelectric plants due to the predominance of hydro plants in electric power generation thermoelectric energy production is basically dependent on hydrology and as a result presents a wide annual variability consequently the investment applied to gas production and transportation infrastructure may become under utilized during a large part of the time thus it is important to find mechanisms apt to improve its utilization in this respect the present work investigates the creation of a flexible market for gas where contracts for flexible gas supply would be offered to industrial users who would receive the gas assigned to thermal power plants when the latter are not dispatched and would resort to an alternate fuel when these plants are dispatched the attractiveness of such a contract would depend of course on its price the purpose of this work is to develop a stochastic model for pricing flexible gas supply contracts taking into account the uncertainty associated to the supply dependent on the dispatch of the thermal power plants which have the priority of use of the gas and the risk profile of potential consumers

a mixed complementarity based equilibrium model of natural gas markets we present a new multiseasonal multiyear natural gas market equilibrium model based on the concept of a competitive equilibrium involving the market participants producers storage reservoir operators peak gas operators pipeline operators marketers and consumers the first three classes are depicted as price takers consistent with perfect competition the pipeline operations are described with regulated tariffs but also involve congestion pricing as a mechanism to allocate scarce pipeline capacity the marketers are price takers in all markets except in sales to consumers in which they compete as nash cournot players finally consumers are described by demand curves for each of the four sectors residential commercial industrial and electric power we show that the equilibrium model is an instance of a mixed nonlinear complementarity problem ncp and provide sufficient detail not generally seen in previous complementarity models of natural gas the ncp formulation is derived from considering the karush kuhn tucker optimality conditions of the optimization problems faced by these participants under mild conditions we show that this ncp has a solution and under additional reasonable conditions we show that the market prices are unique we also validate the model on a representative sample network with nine market participants and three seasons using four scenarios

the effect of informal care on work and wages cross sectional evidence in the united states finds that informal caregivers have less attachment to the labor force the causal mechanism is unclear do children who work less become informal caregivers or are children who become caregivers working less using longitudinal data from the health and retirement study we identify the relationship between informal care and work in the united states both on the intensive and extensive margins and examine wage effects we control for time invariant individual heterogeneity rule out or control for endogeneity examine effects for men and women separately and analyze heterogeneous effects by task and intensity we find modest decreases 2 4 percentage points in the likelihood of working for male caregivers providing personal care female chore caregivers meanwhile are more likely to be retired for female care providers who remain working we find evidence that they decrease work by 3 10hours per week and face a 3 percent lower wage than non caregivers we find little effect of caregiving on working men s hours or wages these estimates suggest that the opportunity costs to informal care providers are important to consider when making policy recommendations about the design and funding of public long term care programs

the chicken or the egg endogeneity in labour market participation of informal carers in england around 14 of the uk labour force has informal care responsibilities and almost everyone in society will be an informal carer in their lifetime a well known fact in the small economic literature on informal care is the apparent negative relation between care responsibilities and labour market participation yet caring and labour market participation may be endogenous using an instrumental variable approach and panel data techniques and employing data from the british household panel study from 1991 to 2002 this paper shows that not accommodating for endogeneity in the labour market participation equation may significantly overestimate the impact care exhibits on the employment decision of informal carers moreover it is shown that a negative impact on employment only applies to some care types policy implications are derived

participation and hours of work two stages in the life cycle of married women abstract a 1979 cross section of dutch households is used to estimate an integrated labor force participation and hours of work labor supply model for women young women and older women are found to behave differently wage and income elasticities are always higher for older than for younger women in absolute terms and the relative importance of participation and hours elasticities is reversed as the average woman grows older thereby implying that younger women tend to be more preoccupied with the participation decision whereas older women are more concerned with the hours decision econometrically the paper builds on heckman s 1974 participation cum hours model by adapting the estimation method to allow for the fact that hours worked are only observed in intervals a maximum likelihood model in which we integrate over parts of the hours distribution is used this technique though computationally involved gave satisfying results we compare the results with estimates of a similar but much simpler probit model to identify the possible biases in the simpler approach

health time allocation and work empirical evidence from turkey abstractthis article investigates the relationship between health status and time allocation decisions of individuals although many studies address impacts of health on labour supply few studies

the opportunity costs of informal care does gender matter in this paper we investigate the costs borne by both male and female carers in terms of their forgone formal employment opportunities traditionally informal care was supplied by women but nowadays women are not only more likely to work but also likely to be significant contributors to family finances for women this implies that the size of any forgone earnings cost of informal care is increasing at the same time population ageing is making for increasing numbers requiring care from a policy perspective it is therefore helpful to consider a less traditional but nevertheless important source of informal care men we find that both male and female carers bear indirect costs in that they are less likely to be in paid work than otherwise similar non carers and when they are in paid work they earn significantly less however we find that the motivation for lower employment participation is not the same for men as it is for women

the labour market costs of community care this paper reports an empirical investigation into the influence of informal care responsibilities on the labour supply of women the objective is to examine the argument that the uk policy of caring for the chronic sick in the community involves a nontrivial opportunity cost in the form of the forgone labour supply of the informal carers upon which it relies we find that informal carers who care for less than 20 h per week are in fact more likely to participate in the labour market but tend to work for fewer hours per week than otherwise similar noncarers informal carers who care for 20 h or more a week are less likely to participate but only slightly however when they do undertake formal employment they tend to earn less per hour and work for fewer hours per week

strategic management of multi year natural gas contracts in electricity markets combined cycle gas turbine ccgt plants show some advantages such as better economies of scale or lower co2 emission rates in comparison to other technologies in addition due to their flexible operation ccgt plants are a useful support for the integration of the growing renewable energy installed capacity consequently during the last years ccgt plants have proliferated in electricity systems increasing the global demand of natural gas ng in order to guarantee the ng supply and to hedge the price volatility electricity generation companies gencos sign supply contracts with ng producers typically ng producers force long term contracts in order to recover their huge capital investments therefore gencos should optimize the exercise of the supply contracts in the long term scope in order to maximize their profits in the electricity market however the optimal exercise of the supply contracts on behalf of the gencos could be impeded because of possible bottlenecks in the ng system accordingly this paper proposes a methodology to incorporate both the characteristics of ng supply contracts and the congestions in the ng system in an electricity market model that could support the decision making process on behalf of the gencos a study case illustrates the methodology

security constrained unit commitment with ac constraints in a restructured power market the independent system operator iso executes the security constrained unit commitment scuc program to plan a secure and economical hourly generation schedule for the day ahead market this paper introduces an efficient scuc approach with ac constraints that obtains the minimum system operating cost while maintaining the security of power systems the proposed approach applies the benders decomposition for separating the unit commitment uc in the master problem from the network security check in subproblems the master problem applies the augmented lagrangian relaxation lr method and dynamic programming dp to solve uc the subproblem checks ac network security constraints for the uc solution to determine whether a converged and secure ac power flow can be obtained if any network violations arise corresponding benders cuts will be formed and added to the master problem for solving the next iteration of uc the iterative process will continue until ac violations are eliminated and a converged optimal solution is found in this paper a six bus system and the ieee 118 bus system with 54 units are analyzed to exhibit the effectiveness of the proposed approach

bidding strategies with fuel supply uncertainty in auctions of long term energy call options this work develops a stochastic optimization model for the creation of a bidding strategy for a generator in an energy call option auction similar to brazil s i e where the bidder can offer both the premium and the strike price the objective of the model is to maximize the bidder s competitiveness while ensuring that the project s target rate of return is achieved with a given probability for example 95 the problem s complexity is compounded by uncertainties in fuel supply and the need to switch between fuels the generators face the conundrum of bidding a single strike price to cover the expenses generated by using multiple types of fuels we address the problem of finding bidding strategies which taking into account uncertainty in fuel supply and risk constraints set the combination of strike price and option premium that ensure a desired risk adjusted return for greenfield dual fuel thermal plants

impact of natural gas system on risk constrained midterm hydrothermal scheduling this paper studies the impact of natural gas ng contracts and constraints on a genco s midterm risk constrained hydrothermal scheduling problem the ng contracts and constraints are modeled as a set of linear equations the proposed model utilizes the stochastic price based unit commitment pbuc the pbuc hourly solution considers uncertainties of market prices for energy and ancillary services uncertainties of natural water inflows and random ng infrastructure interruptions in monte carlo scenarios illustrative examples analyze the genco s risk levels when considering midterm schedules for generating units target payoffs and usages of water inflow ng and other thermal resources simulation results show that a genco s midterm schedules and financial risks could be impacted significantly with the consideration of ng contracts and constraints

the emergence of the working wife in holland the rate of participation in the labor force by married women is lower in the netherlands than in similar industrialized countries however since the end of the second world war the participation rate increased from almost zero to almost one fourth in less than 35 years using estimation results obtained with a probit model on a 1979 nationwide cross section this paper tries to reconstruct the postwar growth in this participation rate it is found in particular that the increase in the real wage for female workers contributes substantially to the explanation of the observed long run change given the relatively high own wage elasticity one would also expect dutch wives to catch up in the future with the level of participation observed in neighboring countries

social security income and the utilization of home care evidence from the social security notch this paper exploits social security law changes to identify the effect of social security income on the use of formal and informal home care by the elderly results from an instrumental variables estimation strategy show that as retirement income increases elderly individuals increase their use of formal home care and become less likely to rely on informal home care provided to them by their children this negative effect on informal home care is most likely driven by male children withdrawing from their caregiving roles the empirical results also suggest that higher social security benefits would encourage the use of formal home care by those who would not have otherwise used any type of home care and would also encourage the use of both types of home care services among elderly individuals

gas generation and wind power a review of unlikely allies in the united kingdom and ireland no single solution currently exists to achieve the utopian desire of zero fossil fuel electricity generation until such time it is evident that the energy mix will contain a large variation in stochastic and intermittent sources of renewable energy such as wind power the increasing prominence of wind power in pursuit of legally binding european energy targets enables policy makers and conventional generating companies to plan for the unique challenges such a natural resource presents this drive for wind has been highly beneficial in terms of security of energy supply and reducing greenhouse gas emissions however it has created an unusual ally in natural gas this paper outlines the suitability and challenges faced by gas generating units in their utilisation as key assets for renewable energy integration and the transition to a low carbon future the single electricity market of the republic of ireland and northern ireland and the british electricity transmission trading agreement market are the backdrop to this analysis both of these energy markets have a reliance on gas generation matching the proliferation of wind power the unlikely and mostly ignored relationship between natural gas generation and wind power due to policy decisions and market forces is the necessity of gas to act as a bridging fuel this review finds gas generation to be crucially important to the continued growth of renewable energy additionally it is suggested that power market design should adequately reward the flexibility required to securely operate a power system with high penetrations of renewable energy which in most cases is provided by gas generation

strategic orientations incentive plan adoptions and firm performance evidence from electric utility firms this study examines the performance implications of the fit between strategic orientations and incentive plan characteristics research hypotheses are based on a framework that draws upon managerial discretion and agency theories to identify the links between firm strategy managerial motivation and control managerial risk bearing and incentive plan characteristics a pooled cross sectional time series research design is used to test hypotheses in a sample of 50 electric utility firms consistent with theory results indicate that annual bonus plans that use cash incentives and accounting measures of performance lead to better performance among firms with defender strategic orientations in contrast firms with prospector strategic orientations realize performance benefits when they adopt stock based incentive plans and use market measures to evaluate managerial performance 1997 john wiley sons ltd

your next of kin or your own career caring and working among the 50 of europe an increasing demand for both formal and informal care is likely to result from the ongoing demographic transition at the same time as there is a further move away from the traditional domestic division of labour public policy making that aims at increasing the supply of informal care necessitates knowledge about the relative importance of various incentives for individual care providers this paper takes as a point of departure that the willingness to supply informal care is partly explained by the extent to which it adversely affects labour market outcomes and analyses the effect on labour market outcomes of providing informal care to one s elderly parent s among the 50 of europe data from share survey of health ageing and retirement in europe was used to examine the association between on the one hand hours of informal care provided and on the other 1 the probability of employment 2 hours worked and 3 wages respectively the results suggest that giving informal care to one s elderly parents is associated with significant costs in terms of foregone labour market opportunities and that these adverse effects vary between countries

do they care too much to work the influence of caregiving intensity on the labour force participation of unpaid caregivers in canada the recent growth of the home care sector combined with societal and demographic changes have given rise to concerns about the adequacy of the supply of family and friend caregivers potential caregivers face competing time pressures that pull them in the direction of the labour market on one hand and towards unpaid caregiving duties on the other this paper examines the influence of unpaid caregiving on the labour supply of a cohort of working aged caregivers in canada with particular emphasis on caregiving intensity results suggest that caregivers are heterogeneous in both their caregiving inputs and associated labour market responses thereby underscoring the importance of controlling for caregiving intensity when measuring labour supply the negative influence of primary caregiving on labour supply appears to be at the level of labour force participation rather than on hours of work or wages

electricity and natural gas interdependency comparison of two methodologies for coupling large market models within the european regulatory framework power generation growth based on natural gas fired power plants ngfpps has lead to increasing interactions between electric power and natural gas industries more companies are progressively and simultaneously participating as big players in both markets however each company has traditionally been settled in one side holding a particular competitive advantage electric power generation companies mainly know how to operate their generation assets whereas gas companies mainly know how to manage their gas supply contracts and make use of often regulated gas assets multi product energy companies have even created independent departments which decisions are usually taken uncoordinatedly in any case companies or departments usually support their decision making process in mathematical tools which represent each market with detail this paper presents two methodologies for coupling two interdependent electricity and gas market models formulated as optimization problems each methodology fulfills different department wishes the electricity perspective methodology maximizes electricity market profits after calculating equivalent gas contracts with the gas market model in contrast the gas perspective methodology minimizes gas operation costs after obtaining the relationship between the marginal revenue and the gas consumption with the electricity market model this coordinated solution would allow companies to obtain synergies resulting in a competitive advantage over other companies that operate uncoordinatedly in both markets

dynamic wage and employment effects of elder parent care this article formulates and estimates a dynamic discrete choice model of elder parent care and work to analyze how caregiving affects a woman s current and future labor force participation and wages the model incorporates parental health changes human capital accumulation and job offer availability the estimates indicate that women face low probabilities of returning to work or increasing work hours after a caregiving spell i use the estimated model to simulate the caregiving employment and welfare effects of a longer unpaid work leave than currently available under the family and medical leave act a paid leave and a caregiver allowance

coordination between medium term generation planning and short term operation in electricity markets this paper analyzes the coordination between medium term generation planning and short term operation in electricity markets this coordination is particularly important from a practical point of view in order to guarantee that certain aspects of the operation that arise in the medium term level are explicitly taken into account limited energy resources and obligatory use resources three different approaches are proposed in order to guarantee that short term decisions made by a generation company are consistent with its operation objectives formulated from a medium term perspective these approaches make use of technical and economic signals to coordinate both time scopes primal information dual information and resource valuation functions this paper presents the main advantages and drawbacks of the three approaches and applies them to a case study that uses a conjectural variation based representation of the market

optimizing short term natural gas supply portfolio for electric utility companies natural gas fired power plants ngfpp are important electricity generation resources in the united states optimizing the natural gas supply portfolio especially the short term portfolio is critical for the day to day operations and the financial performance of ngfpps traditionally such optimization problems are solved using cost minimization based frameworks however such frameworks are facing challenges due to the lack of consideration of associated financial risks in the current deregulated electricity markets which the electric utility companies eucs who own and operate ngfpps now bear this paper presents a utility maximization based framework to optimize the short term natural gas supply portfolio for the euc it considers the financial risks associated with the portfolio and incorporates the risk preferences of the eucs as decision maker dm in the portfolio optimization process an application of the proposed framework is provided and its results show that the proposed framework is more desirable in terms of risk cost trade off optimization

hourly electricity demand response in the stochastic day ahead scheduling of coordinated electricity and natural gas networks this paper studies the role of hourly economic demand response in the optimization of the stochastic day ahead scheduling of electric power systems with natural gas transmission constraints the proposed coordinated stochastic model referred to as egtran considers random outages of generating units and transmission lines and random errors in forecasting the day ahead hourly loads the monte carlo simulation is applied to create multiple scenarios for representing the coordinated system uncertainties the nonlinear natural gas network constraints are linearized and incorporated into the stochastic model numerical results demonstrate the benefits of applying the hourly economic demand response for enhancing the scheduling coordination of natural gas and electricity networks it is demonstrated that electricity demand response would offer a less volatile hourly load profile and locational marginal prices and less dependence on natural gas constraints for the optimal operation of electric power systems the proposed model for egtran could be applied by grid operators for the hourly commitment and dispatch of power system units

informal care and long term labor market outcomes in this paper we estimate long run effects of informal care provision on female caregivers labor market outcomes up to eight years after care provision we compare a static version where average effects of care provision in a certain year on later labor market outcomes are estimated to a partly dynamic version where the effects of up to three consecutive years of care provision are analyzed our results suggest that there are significant initial negative effects of informal care provision on the probability to work full time the reduction in the probability to work full time by 4 percentage points or 2 4 5 0 if we move from point to partial identification is persistent over time short run effects on hourly wages are zero but we find considerable long run wage penalties

the political economy of long term care we build a two dimensional political economy model to explain the provision and financing of long term care and income redistribution voting agents differ in need and income opening up two conflicts one sets families with disabled parents who are in favor of a public long term care program against the ones without such parents who oppose public financing the other sets the poor against the rich with the former preferring heavier income taxation than the latter we show that a structure induced equilibrium always exists and that it is unique if informal care is provided in equilibrium the equilibrium not only explains the negative association of income inequality and long term care financing but also allows predictions about how demographic change might impact long term care arrangements and expenses

linear complementarity models of nash cournot competition in bilateral and poolco power markets two cournot models of imperfect competition among electricity producers are formulated as mixed linear complementarity problems lcps and a simple example is presented to illustrate their application the two models simulate bilateral markets the models include a congestion pricing scheme for transmission but other transmission pricing approaches can also be represented in this framework the two models differ from each other in that one has no arbitrage between nodes of the network while in the other model arbitragers erase any noncost based differences in price the latter bilateral model turns out to be equivalent to a cournot model of a poolco the models differ from other cournot market models in that they include both of kirchhoff s laws via a dc approximation can include arbitragers possess unique solutions and are readily solved by efficient lcp algorithms the key assumption that permits their formulation as lcps is that each producer naively assumes that its output will not affect transmission prices

multi stage flexible expansion co planning under uncertainties in a combined electricity and gas market natural gas is an important fuel source in the power industry electricity and natural gas are both energy that can be directly consumed to improve the overall efficiency of the energy infrastructure it is imperative that the expansion of gas power plants electricity transmission lines and gas pipelines can be co planned the co planning process is modeled as a mixed integer nonlinear programming problem to handle conflicting objectives simultaneously we propose a novel model to identify the optimal co expansion plan in terms of social welfare to evaluate the robustness of plans under different scenarios the flexibility criterion is used to identify each plan s adaptation cost to uncertainties such as demand growth fuel cost and financial constraints etc we developed a systematic and comprehensive planning model to understand develop and optimize energy grids in order to reach higher social welfare and is therefore of great importance in terms of supporting and guiding investment decisions for the power and gas industry meanwhile we use the sequential importance sampling sis to perform scenario reduction for achieving a higher computational efficiency a comprehensive case study on the integrated ieee 14 bus and a test gas system is conducted to validate our approach