Optimal Consumption Decisions Research Articles

Estimating sentiment and risk in a consumption model: a factor analysis approach

Abstract This empirical paper deals with the impacts of sentiment about the future, short-run risk, and long-run risk in a dynamic economic model of optimal consumption decisions with Schroder and Skiadas [(1999) Journal of Economic Theory 89, 68–126.] continuous-time stochastic recursive preferences. The empirical strategy combines both a latent factor method and a democratic orthogonalization technique. The latent factor method is applied to a large database of macroeconomic indicators, and a democratic orthogonalization technique is used to separate the relative importance of sentiment about the future and long-run risk channels in shaping optimal consumption decisions. The empirical results suggest that consumers with recursive preferences are not indifferent to long-run uncertainty shocks to future consumption prospects. Endogenous consumption variations are driven by a multicomponent mechanism, where on average, the sentiment component accounts for 15.33%, the short-run risk accounts for 16.89%, and the long-run risk pertains to 34.51%.

Optimal consumption and portfolios with the hyperbolic absolute risk aversion preference under the CEV model

This paper studies the optimal investment-consumption decision under the constant elasticity of variance (CEV) model for an individual seeking to maximize the expected utility from cumulative consumption plus the expected utility from terminal wealth. Due to the fact that different individuals may have different risk preferences, we assume that the risk preference of an individual satisfies a hyperbolic absolute risk aversion (HARA) utility function. Generally speaking, power utility function, logarithmic utility function and exponential utility function widely used in investment theory are usually special cases of HARA utility function. By using the principle of dynamic programming and Legendre transform-dual technique, we obtain the explicit expression of the optimal investment-consumption decision. In addition, we derive the results under other utility functions as well and analyze some characteristics of the optimal portfolios and the optimal consumption decisions. A numerical simulation is presented to illustrate our results. Research results suggest that the optimal investment decisions between with consumption behavior and without it have considerable differences.

Consumer default and optimal consumption decisions

PurposeThe authors examine the optimal consumption decisions of households in a micro-founded framework that introduces endogenous default. They study default in the context of a two-period process, assuming three non-overlapping steps of non-payment: delinquency, non-performing loans and bankruptcy (default).Design/methodology/approachIn their model, the authors extend the analysis of loan default to two periods and include agent heterogeneity by considering also saving households. In the optimization problem, the authors obtain first-order conditions for borrowers who do not repay all of their loans (comparing them to those who fully repay them) and also for savers. In addition, by using nonlinear Generalized Method of Moments (GMM), they obtain consistent estimates of the household preference parameters and present the impulse responses of borrowers' consumption to demand shocks.FindingsThe authors derive an augmented consumption Euler equation for borrowers, which is a function inter alia of an expected default factor. They estimate this equation and find non-negligible differences in preference parameters relative to values reported in the literature. Further, an ordering by size of the household discount factors is provided empirically. Finally, the impulse responses of borrowers' consumption to a demand shock are found to last more for borrowers who do not fully repay their debts.Originality/valueThis work represents a promising line of research by introducing default in one of the basic components of DSGE models, making the latter more appropriate for analyzing monetary and macro-prudential policies.

Optimal consumption decisions of family networks with similar felicity functions

Family networks have increased at an accelerated pace through social networking through social networking services, online platforms, and social media clubs. This paper develops a model of an economy populated by networks of families with similar preferences (the same functional form of the felicity or utility function) but family members differ in their deep parameters (compulsion for consumption and risk tolerance), which, in turn, leads to some kind o heterogeneity among the families. In this context, the problem of felicity (utility) maximization of the average family in the network is solved. The optimal path of consumption is obtained for the average family and graphical comparative static exercises are performed. Finally, the economic welfare of the typical family in a network is calculated and comparative static experiments are carried out. This approach improves the understanding of the consumption decision making of families interacting in social networking services.

Fiscal Policy and Urban and Rural Residents’ Marginal Propensity to Consume

Based on the optimal consumption decisions of representative households and the relationship between their decisions and fiscal policy, we evaluate the impact of China’s fiscal policy on urban and rural residents’ marginal propensity to consume. The result shows that since 1998 marginal propensity to consume has decreased by more than 20 percent, and the decrease is not only due to income distribution, economic development level, expectations, consumption structure and other factors, but also closely related to the application of fiscal policy. Among these factors, the overall impact of unanticipated fiscal policy shocks is significant and negative. The policy option of using unforeseen increases in tax revenue as a financing instrument greatly diminishes the positive effects of structural adjustment. Therefore, to increase household consumption, it is necessary not only to raise residents’ capacity for consumption by increasing fiscal revenue but also to stabilize consumer expectations and promote the marginal propensity to consume through adjusting fiscal revenue and expenditure policies.

Revisiting the effect of household size on consumption over the life-cycle

Although the link between household size and consumption has strong empirical support, there is no consistent way in which demographics are dealt with in standard life-cycle models. We study the relationship between the predictions of the Single Agent model (the standard in the literature) versus a simple model extension (the Demographics model) where deterministic changes in household size and composition affect optimal consumption decisions. We show theoretically that the Demographics model is conceptually preferable to the Single Agent model as it captures economic mechanisms ignored by the latter. However, our quantitative analysis demonstrates that differences in predictions for consumption are negligible across models, when using standard calibration strategies. This suggests that it is largely irrelevant which model specification is used.

A CONCISE CHARACTERIZATION OF OPTIMAL CONSUMPTION WITH LOGARITHMIC PREFERENCES

In a general semi-martingale financial market with possibly nonlinear wealth dynamics, incomplete information, and ambiguity, we show that the optimal consumption decision of an agent with logarithmic preferences can be separated from the agent's investment decisions. Using minimal assumptions and mathematical machinery, we demonstrate that the optimal consumption/wealth ratio is deterministic, and we derive an explicit formula for it.

Life-Cycle Consumption: Can Single Agent Models Get it Right?

Although the link between household size and consumption has strong empirical support, there is no consistent way in which demographics are dealt with in standard life-cycle models. We study the relationship between the predictions of the Single Agent model (the standard in the literature) versus a simple model extension (the Demographics model) where deterministic changes in household size and composition affect optimal consumption decisions. We show theoretically that the Demographics model is conceptually preferable to the Single Agent model as it captures economic mechanisms ignored by the latter. However, our quantitative analysis demonstrates that differences in predictions for consumption are negligible across models, when using standard calibration strategies. This suggests that it is largely irrelevant which model specification is used.

Can Fuzzy Decision-Making Explain Growing Consumption During Eras of Negative Real Interest Rates?

Treatment of fuzziness as a distinct source of uncertainty in intertemporal consumption models allows for explicit modeling of the eect of consumers' optimism-pessimism on optimal consumption decisions. By exploring the use- fulness of this particular feature in uncovering the 'excessive consumption growth'puzzle we demonstrate in simple two-period life-cycle settings that there are some reasonable ranges of individuals'optimism-pessimism and risk- aversion for which the optimal consumption is expected to grow 'excessively' despite negative real interest rate

Life-cycle consumption under social interactions

Abstract In this paper we examine how social interactions affect consumption decisions at various levels of aggregation in a life-cycle economy made up of peer groups. For this purpose, we consider two analytically solvable life-cycle models, one under certainty equivalent behavior and one under prudence, and explicitly allow for three different forms of social interactions in peer groups, namely conformism, altruism, and jealousy. We show that whether social interactions have any effects on individuals’ optimal consumption decisions critically depends on intertemporal rather than static considerations. This is true regardless of whether individuals’ preferences are time separable or exhibit habit formation, and whether information within peer groups is homogeneous or disparate. It implies that analyzing the effects of social interactions in static rather than intertemporal settings is likely to be misleading. We also show that social interactions, when coupled with either habit formation or prudence, can significantly strengthen the effects of habit formation or prudence in the direction of resolving two well-known puzzles in the literature on the permanent income hypothesis, namely excess smoothness and excess sensitivity.

Do Addicts Behave Rationally?

The theory of rational addiction assumes that addicts' behavior is fully rational. Common sense and psychological introspection suggest, however, that addictive behavior is irrational. Without knowledge of the addicts' preferences this dispute cannot be resolved. This paper reports the results of an experiment in which addictive preferences were induced. It turns out that ‘addicts’ consume systematically too much compared to the optimal consumption decision. We explain this systematic excess consumption in terms of the psychologically salient features of addictive goods.

Optimal intertemporal consumption decisions under the threat of starvation

This paper studies consumption and saving decisions over time in a life cycle model in which survival from one period to the next is endogenous. Survival probabilities depend on health, which is a capital stock subject to depreciation and which can be augmented by consumption (nutrition). Borrowing is ruled out in our model and we investigate optimal consumption decisions when income fluctuates at seasonal frequencies and when income follows a stochastic process. Among other results, we show that understanding the pattern of income is necessary for understanding consumption decisions when survival is probabilistic and endogenous.

Savings and Consumption with an Uncertain Horizon

This paper studies the effect of lifetime uncertainty on optimal consumption decisions. It is shown that for risk averters changing the distribution of lifetime uncertainty decreases consumption due to the higher probability of having a longer life and increases consumption due to the desire for sure consumption in the present. The stronger of these effects determines the effect of lifetime uncertainty on optimal consumption decisions. The major result is that if the utility function is Cobb-Douglas and the rate of return is not too large relative to the amount of future discounting then lifetime uncertainty will always increase consumption.

Uncertainty and Optimal Consumption Decisions

linear production function, that for some utility functions the optimal initial consumption in the random case decreases for all values of initial wealth as compared with the initial consumption in the deterministic case. For other utility functions the optimal consumption always increases. Hence it seems, from these examples, that two divergent forces are at work. The first is the desire to consume more initially as a hedge against the uncertain future. The second force is the desire to consume less initially so as to increase the future consumption prospects. (It is assumed, of course, that increased inputs increase outputs for all possible random events, or states of the world). The relative strength of each of these forces, as implied by the utility function, is the key to the relationship between random consumption and deterministic consumption in this model. The major conclusion of this paper is that the qualitative difference between optimal consumption decisions in the two different models is very strongly influenced by the shape of the utility function. In particular the third derivative of the utility function plays a rather large role. It is this derivative that determines the attitude toward the skewness of a distribution in the theory of portfolio choices, as may be seen from the analysis of Pratt [7] and Tobin [10]. Even in these models, however, the third derivative cannot be ignored, since ignoring skewness distorts the results. Moreover, there does not seem to be any intuitive economic reason to make any assumptions concerning the third derivative of the utility function. The extent to which the utility function influences savings and consumption decisions is exhibited in a precise manner. It may be shown that the qualitative relationship between random and deterministic consumption depends in general on the initial wealth. It is not true, as one would infer from the papers cited above, that random consumption is always either greater than or less than deterministic consumption independently of the initial wealth. In other words, for many utility functions the initial wealth turns out to be a decisive factor in the qualitative relationship between the random and deterministic case. Naturally this relationship will also normally depend on -the probabilistic structure of the model. The key result of this paper is a theorem which gives a necessary and sufficient condition for determining the qualitative relationship between random consumption and deterministic consumption. This condition, which is both necessary and sufficient, is in a particularly simple form in that it depends only on the known parameters of the model (i.e., the production function, the utility function, and the distribution of the random variable) and also on the optimal deterministic policy which, in general, is much simpler to exhibit than its counterpart in the random case.