The Non-Superneutrality of Money and its Distributional Effects when Agents are Heterogeneous and Capital Markets are Imperfect

In this paper we develop an OLG model with heterogeneous agents, money and bequests, introducing occupational choice and financing constraints when capital markets are imperfect. We show how, under appropriate conditions, all the moments of the distribution are affected by changes in money growth. More precisely, if capital markets are imperfect and heterogeneous agents are liquidity constrained, investment in fixed capital is not efficient and aggregate wages and profits depend on the availability of loanable funds. An increase in money growth may imply a more efficient aggregate investment. Therefore aggregate product and wealth positively depend on an acceleration in money growth.

Was Bernanke Right? Targeting Asset Prices may not be a Good Idea after all

Should the central bank prevent “excessive” asset price dynamics or should it wait until the boom spontaneously turns into a crash and intervene only afterwards? The debate over this issue goes back at least to the exchange between Bernanke-Gertler (BG) and Cecchetti but has not settled yet. In their 1999 paper BG claimed that price stability and financial stability are ‘highly complementary and mutually consistent objectives’ in a flexible inflation targeting regime which ‘dictates that central banks ... should not respond to changes in asset prices, except insofar as they signal changes in expected inflation.’ (BG, 1999, p.18). This conclusion is straightforward within the variant of the NK-DSGE framework used by BG in which asset inflation shows up as a factor ‘augmenting’ the IS curve. In the present paper, we pursue a different modelling strategy so that, in the end, asset price dynamics will be incorporated into the NK Phillips curve. In our context it is not true anymore that by focusing on inflation the central bank is also checking an asset price boom. We put ourselves, therefore, in the best position to obtain a significant stabilizing role for asset price targeting. It turns out, however, that inflation volatility is higher in the asset price targeting case. After all, therefore, targeting asset prices may not be a good idea.cost channel, asset prices, Taylor rules

A look at the relationship between industrial dynamics and aggregate fluctuations

The firmly established evidence of right-skewness of the firms’ size distribution is generally modelled recurring to some variant of the Gibrat’s Law of Proportional Effects. In spite of its empirical success, this approach has been harshly criticized on a theoretical ground due to its lack of economic contents and its unpleasant long-run implications. In this chapter we show that a right-skewed firms’ size distribution, with its upper tail scaling down as a power law, arises naturally from a simple choice-theoretic model based on financial market imperfections and a wage setting relationship. Our results rest on a multi-agent generalization of the prey-predator model, firstly introduced into economics by Richard Goodwin forty years ago.Firm size; Prey-predator model; Business Fluctuations

Credit Cycles in a OLG Economy with Money and Bequest

In this paper we develop an extended version of the original Kiyotaki and Moore's model ("Credit Cycles" Journal of Political Economy, vol. 105, no 2, April 1997)(hereafter KM) using an overlapping generation structure instead of the assumption of infinitely lived agents adopted by the authors. In each period the population consists of two classes of heterogeneous interacting agents, in particular: a financially constrained young agent (young farmer), a financially constrained old agent (old farmer), an unconstrained young agent (young gatherer), an unconstrained old agent (old gatherer). By assumption each young agent is endowed with one unit of labour. Heterogeneity is introduced in the model by assuming that each class of agents use different technologies to pro- duce the same non durable good. If we study the effect of a technological shock it is possible to demonstrate that its effects are persistent over time in fact the mechanism that it induces is the reallocation the durable asset ("land")among agents. As in KM we develop a dynamic model in which the durable asset is not only an input for production processes but also collateralizable wealth to secure lenders from the risk of borrowers'default. In a context of intergenerational altruism, old agents leave a bequest to their offspring. Money is a means of payment and a reserve of value because it enables to access consumption in old age. For simplicity we assume that preferences are defined over consumption and bequest of the agent when old. Money plays two different and contrasting roles with respect to landholding. On the one hand, given the bequest, the higher the amount of money the young wants to hold, the lower landholding. On the other hand the higher the money of the old, the higher the resources available to him and the higher bequest and landholding. We study the complex dynamics of the allocation of land to farmers and gatherers - which determines aggregate output - and of the price of the durable asset. If a policy move does not change the ratio of money of the farmer and of the gatherer, i.e. if the central bank changes the rates of growth of the two monetary aggregates by the same amount, monetary policy is superneutral, i.e. the allocation of land to the farmer and to the gatherer does not change, real variables are unaffected and the only e¤ect of the policy move is an increase in the rate of inflation, which is pinned down to the (uniform) rate of change of money, and of the nominal interest rate. If, on the other hand, the move is differentiated, i.e. the central bank changes the rates of growth of the two monetary aggregates by different amounts so that the rates of growth are heterogeneous, money is not superneutral, i.e. the allocation of land changes and real variables are permanently affected, even if the rates of growth of the two aggregates go back to the original value afterwardsCredit Cycles, monetary policy

Adaptive microfoundations for emergent macroeconomics

In this paper we present the basics of a research program aimed at providing microfoundations to macroeconomic theory on the basis of computational agentbased adaptive descriptions of individual behavior. To exemplify our proposal, a simple prototype model of decentralized multi-market transactions is offered. We show that a very simple agent-based computational laboratory can challenge more structured dynamic stochastic general equilibrium models in mimicking comovements over the business cycle.Microfoundations of macroeconomics, Agent-based economics, Adaptive behavior

Weird Ties? Growth, Cycles and Firm Dynamics in an Agent-Based Model with Financial-Market Imperfections

This paper studies how the interplay between technological shocks and financial variables shapes the properties of macroeconomic dynamics. Most of the existing literature has based the analysis of aggregate macroeconomic regularities on the representative agent hypothesis (RAH). However, recent empirical research on longitudinal micro data sets has revealed a picture of business cycles and growth dynamics that is very far from the homogeneous one postulated in models based on the RAH. In this work, we make a preliminary step in bridging this empirical evidence with theoretical explanations. We propose an agent-based model with heterogeneous firms, which interact in an economy characterized by financial-market imperfections and costly adoption of new technologies. Monte-Carlo simulations show that the model is able jointly to replicate a wide range of stylised facts characterizing both macroeconomic time-series (e.g. output and investment) and firms' microeconomic dynamics (e.g. size, growth, and productivity).Financial Market Imperfections, Business Fluctuations, Economic Growth, Firm Size, Firm Growth, Productivity Growth, Agent-Based Models.

Heterogeneous Firms and International Trade: The Role of Productivity and Financial Fragility

Starting from the premise that productivity is heterogeneous across firms, Melitz (2003) explains why individual productivity is key in determining the capability of a firm to export. In this paper we build a model along Melitz’s lines to show that also financial capacity, captured by the level of individual net worth, affects the behaviour of firms on international markets. We show that firms with low productivity may still be able to penetrate foreign markets provided they have enough net worth to incur the cost of exporting. In this setting, we explore the effects of changes in transport costs, fixed costs for exporters and of financial constraints

Weird ties? Growth, cycles and firm dynamics in an agent-based model with financial-market imperfections

This paper studies how the interplay between technological shocks and financial variables shapes the properties of macroeconomic dynamics. Most of the existing literature has based the analysis of aggregate macroeconomic regularities on the representative agent hypothesis (RAH). However, recent empirical research on longitudinal micro data sets has revealed a picture of business cycles and growth dynamics that is very far from the homogeneous one postulated in models based on the RAH. In this work, we make a preliminary step in bridging this empirical evidence with theoretical explanations. We propose an agent-based model with heterogeneous firms, which interact in an economy characterized by financial-market imperfections and costly adoption of new technologies. Monte-Carlo simulations show that the model is able jointly to replicate a wide range of stylised facts characterizing both macroeconomic time-series (e.g. output and investment) and firms' microeconomic dynamics (e.g. size, growth, and productivity)