Utility functions, future consumption targets and subsistence thresholds

If the consumers risk aversion behavior varies intertemporally and if the risk aversion coefficient on future consumption becomes very large, the consumer tends to aim at a fixed future consumption target. A by-product is a reinterpretation of subsistence theories of consumption.Intertemporal Consumer Choice, theories of consumption, risk aversion coefficient

Throughput Maximization for UAV-Aided Backscatter Communication Networks

This paper investigates unmanned aerial vehicle (UAV)-aided backscatter communication (BackCom) networks, where the UAV is leveraged to help the backscatter device (BD) forward signals to the receiver. Based on the presence or absence of a direct link between BD and receiver, two protocols, namely transmit-backscatter (TB) protocol and transmit-backscatter-relay (TBR) protocol, are proposed to utilize the UAV to assist the BD. In particular, we formulate the system throughput maximization problems for the two protocols by jointly optimizing the time allocation, reflection coefficient and UAV trajectory. Different static/dynamic circuit power consumption models for the two protocols are analyzed. The resulting optimization problems are shown to be non-convex, which are challenging to solve. We first consider the dynamic circuit power consumption model, and decompose the original problems into three sub-problems, namely time allocation optimization with fixed UAV trajectory and reflection coefficient, reflection coefficient optimization with fixed UAV trajectory and time allocation, and UAV trajectory optimization with fixed reflection coefficient and time allocation. Then, an efficient iterative algorithm is proposed for both protocols by leveraging the block coordinate descent method and successive convex approximation (SCA) techniques. In addition, for the static circuit power consumption model, we obtain the optimal time allocation with a given reflection coefficient and UAV trajectory and the optimal reflection coefficient with low computational complexity by using the Lagrangian dual method. Simulation results show that the proposed protocols are able to achieve significant throughput gains over the compared benchmarks

Prototype Boiling Ketupat Type of Batch Study of Heat Transfer Coefficient Into Condensor

So far for producing ketupat done using boiling system open by using a regular steamer so much heat loss occurs due to his high consumption of fuel, to reduce the fuel consumption of the writers tried to make a prototype of a batch type boiling ketupat equipped with condenser.Purpose to condensation steam in boiling water so that it does not require the addition of water.Energy consumption in a way traditional ketupat boiling takes time for 4 hours for all processes with the same time as that of 285000 kJ/kg while using a prototype wave energy consumption i.e. batch type of 37341 kJ/kg for cooling fluid flow rate 5 lt/min, 37802 kJ/kg for cooling fluid flow rate 10 lt/min and 46100 Lt/min for the coolant flow rate 15 lt/min. Influence of flow rate of cooling fluid on the heat transfer coefficient is proportional, the greater the flow rate of cooling fluid then the greater the coefficient of heat transfer rates. This is due to the heat lost when still on the way to the condenser and heat lost due to contact between the condenser with outside air

Does Consumer Confidence Forecast Household Spending? The Euro Area Case

The following analysis, based on error correction models, suggests that consumer confidence, together with traditional macroeconomic variables, contains a forecasting and explicative power on consumption. By including consumer confidence in a consumption function, consumer confidence releases a significant coefficient. Such a confidence-augmented consumption model provides good forecasting results.Consumer confidence; consumption function; forecasting; consumer attitudes and behaviour; households

"The Economic Consequences of Weintraub's Consumption Coefficient"

In this paper we show that Weintraub:s consumption coefficient (the ratio of total consumption to wages) can elucidate trends in the sectoral and functional distributions of income We also show that, in a Kaleckian model, it simplifies and add precision to Kaleckian macroeconomics. Using a Kaleckian definition of profits, empirical estimates of the coefficient are presented for the UK 1972-1990. From a level of around 1.1 in the 1970’s, the coefficient rose to around 1.3 in the mid-1980s from which it has started to fall back to its 1970's levels. During the 1980s, the coefficient indicated a marked redistribution of income in favour of profits along with a rise in capitalists' propensity to consume. This confirms the evidence that the economic boom of the 1980s was driven principally by an expansion of demand for luxury goods rather than fixed capital investment. This will have been a factor in the slump after 1990.

Intertemporal consumption choices, transaction costs and limited participation to financial markets: reconciling data and theory

This paper builds a unifying framework that, within the theory of intertemporal consumption choices, brings together the limited participation -based explanation of the poor empirical performance of the C-CAPM and the transaction costs-based explanation of incomplete portfolios. Using the implications of the consumption model and observed household consumption and portfolio choices, we identify the preference parameters of interest and a lower bound for the costs rationalizing non-participation in financial markets, in the presence of unobserved heterogeneity in tastes for consumption and portfolio allocation. Using the US Consumer Expenditure Survey and assuming isoelastic preferences, we estimate the coefficient of relative risk aversion at 1.7 and a cost bound of 0.4 percent of non-durable consumption. Our estimate of the preference parameter is theoretically plausible and the bound sufficiently small to be likely to be exceeded by the actual total (observable and unobservable) costs of participating to financial markets

Utility-based Pricing of the Weather Derivatives

Since the underlying of the weather derivatives is not a traded asset, these contracts cannot be evaluated by the traditional financial theory. Cao and Wei (2004) price them by using the consumption-based asset pricing model of Lucas (1978) and by assuming different values for the constant relative risk aversion coefficient. Instead of taking this coefficient as given, we suggest in this paper to estimate it by using the consumption data and the quotations of one of the most transacted weather contracts which is the New York weather futures on the Chicago Mercantile Exchange (CME). We apply the well-known generalized method of moments (GMM) introduced by Hansen (1982) to estimate it as well as the simulated method of moments (SMM) attributed to Lee and Ingram (1991) and Duffie and Singleton (1993). This last method is studied since it is presumed to give satisfactory results in the case of the weather derivatives for which the prices are simulated. We find that the estimated coefficient from the SMM approach must have improbably high values in order to have the calculated weather futures prices matching the observations.weather derivatives; consumption-based asset pricing model; constant relative risk aversion utility function; generalized method of moments; simulated method of moments; HAC matrix; Monte-Carlo simulations; periodic variance; GARCH

Demographic Trends and Consumption Inequality in Australia 1975-1993

We examine trends in consumption inequality among Australian households using the Australian Bureau of Statistics Household Expenditures Surveys collected over the period 1975 to 1993. We find that consumption is much more equal than income and that both income and consumption inequality rose by significant amounts over the period. However, consumption inequality rose by much less (the Gini coefficient for income inequality rose by 17% while that for nondurable consumption rose by 9%). We then examine the effects of demographic trends, specifically population ageing and changing family structures, and find they account for only a minor fraction in the overall growth in economic inequality.

Relative wage movements and the distribution of consumption

We analyze how relative wage movements across birth cohorts and education groups during the 1980s affected the distribution of household consumption. The analysis integrates the labor economics literature on time variation in the wage structure with the consumption insurance literature. In contrast to previous tests of consumption insurance, we examine the impact of systematic, publicly observable shifts in the hourly wage structure. To circumvent the extreme scarcity of longitudinal data with high quality information on both consumption and labor market outcomes, we draw upon the best available cross-sectional data sources to construct synthetic panel data on consumption, labor supply and wages. We find that low-frequency movements in the cohort-education structure of pre-tax hourly wages drove large changes in the distribution of household consumption. The results constitute a spectacular failure of the consumption insurance hypothesis, and one that is not explained by existing theories of informationally constrained optimal consumption allocations. We also develop a procedure for assessing the welfare consequences of deviations from full consumption insurance and, in particular, from the failure to insulate the consumption distribution from relative wage shifts across cohort-education groups. For a coefficient of relative risk aversion equal to two, fully insulating households from group-specific endowment variation would raise welfare by an amount equivalent to a uniform 2.7% consumption increase

Intertemporal Asset Pricing Without Consumption Data

This paper proposes a new way to generalize the insights of static asset pricing theory to a multi-period setting. The paper uses a loglinear approximation to the budget constraint to substitute out consumption from a standard intertemporal asset pricing model. In a homoskedastic lognormal selling, the consumption-wealth ratio is shown to depend on the elasticity of intertemporal substitution in consumption, while asset risk premia are determined by the coefficient of relative risk aversion. Risk premia are related to the covariances of asset returns with the market return and with news about the discounted value of all future market returns.