INEQUALITY AND AGGREGATE DEMAND IN THE IS‐LM AND IS‐MP MODELS

This paper presents an extension to the textbook IS‐LM and IS‐MP models that allows the short run effects of an increase in household income inequality to be studied in a simple manner. The income distribution is assumed to be log‐normal, and the coefficient of variation of income is assumed to be exogenous. The latter is used as the measure of income inequality, and enters otherwise standard IS and LM curves in a straightforward manner. While the models are highly stylised, they can easily be extended to more complicated variants.     

Econometric diagnostics to distinguish between the IS curve and the Ricardian equivalence

In this article two different specifications of a macroeconomic model are analysed. The first model is the Keynesian IS (Investments–savings) curve. The second is derived from the New Classical Ricardian equivalence. Since the two specifications are observationally equivalent, including the same set of variables, the econometric diagnostics of the regression equations are used to differentiate between the two of them. Six statistical criteria are compared: serial correlation, heteroscedasticity, specification tests, fit, randomness, and normality. The results support much better Ricardian equivalence than the Keynesian IS model.     

A new route to cyclical strategies in two-dimensional optimal control models

This paper proposes a new route to rationalize cyclical policies in concave two-state variable, economic control problems. The essential ingredients are: positive growth; a (positive) externality of the stock; and sluggish control, such that actual control is the sum over historical changes. Given these conditions, it is amazingly simple to generate stable limit cycles, even for separable models. A simple renewable resource model is used to verify this claim.     

A Comparison of Four Macroeconometric Models of the Australian Economy*

For more than a decade, macroeconometric models have been used in Australia as tools in policy analysis and as aids in the task of forecasting major economic variables. Until recently, however, not much work had been done in comparing these models. Challen and Hagger (1979a, 1979b) provide a useful introduction to existing Australian models which includes a summary of simulation studies previously undertaken with these models. In the current paper, the economic content of four of these models is summarized in a simple theoretical framework. Simulation analysis is also used to examine the dynamic adjustment mechanisms associated with the theoretical structure of each model. A general conclusion of this paper is that more work is needed on model evaluation in Australia, based on a wider range of criteria than have been used in the past.     

Financial constraints and the balance sheet channel: a re-interpretation

Aggregate demand models extending IS/LM fixed price framework yield an enhancement mechanism of the traditional monetary transmission mechanism, the credit channel, which, according to the credit view, works through the ‘balance sheet channel’ and the ‘bank lending channel’. In this paper the augmented IS/LM model is modified assuming that investments may be financed by both internal and external sources of funds. The inclusion of internal funds in the augmented IS/LM fixed price model suggests a different interpretation of the ‘balance sheet channel’ as an enhancement mechanism amplifying monetary policy effects through the quantity rather than the cost of borrowing. Thus, changes in borrowers’ net worth over the cycle can amplify and propagate output fluctuations directly rather than indirectly as in the traditional interpretation of the balance sheet channel. The empirical analysis of the monetary transmission mechanism for Italy in the last decade accords with the interpretation of the balance sheet channel proposed in this paper.     

Innovation strategies and firm performance: Simple or complex strategies?

This paper analyzes the effect of various innovation strategies (ISs) of firms on their future performance, captured by labor productivity. Using five waves of the Community Innovation Survey in Sweden, we have traced the innovative behavior of firms over a decade, that is, from 2002 to 2012. We defined ISs to be either simple or complex (in various degrees). We call an IS a simple IS when firms engage in only one of the four types of Schumpeterian innovations, that is, product, process, marketing, or organizational, while a complex IS is when firms simultaneously engage in more than one type. The main findings indicate that those firms that choose and afford to have complex ISs are better off in terms of their future productivity in comparison with those firms that choose not to innovative (base group) and also in comparison with those firms that choose simple ISs. The results are mostly robust for those complex innovators that have a higher degree of complexity and also keep the balance between technological (product and process) and non-technological (organizational and marketing) innovations.     

On interpreting probability distributions fitted to times of first adoption

This paper attempts to interpret the standard statistical distributions in the innovation diffusion context. A simple rule is provided for classifying a statistical distribution as being an internal, an external, or a mixed influence model. Two distributions, suitable as flexible mixed influence models, are used to analyze several well-known data sets.     

大规模定制系统结构与成功要素研究

在深入研究大规模定制（MC）与信息系统管理的相关文献的基础上,本文构建了大规模定制系统结构模型、信息化过程模型、MC业务流程与企业信息系统关系模型、信息化要素分析模型、信息化成功要素模型,以作为深入研究大规模定制模式和大规模定制企业信息化模式,构建大规模定制企业信息管理体系的理论指导。     

Monetary Stabilisation Policy in a Monetary Union: Some Simple Analytics

We do two things in this paper. First, we look at some simple models of monetary decision making in a monetary union and ask how much more variable a country's output and inflation is likely to be if it joins the union. We answer this analytically and then go on to 'calibrate' the simple model. The model has few structural equations, but it is useful in allowing us to examine how the variability of output and inflation are likely to change as key parameters change. Our conclusions on this front are likely to be sensitive to model specification. However, we also identify a second best issue concerning the optimal make–up of the monetary union which is likely to be more robust: namely that only when all members of the union have the same structural parameter values (and shocks are perfectly correlated) will it be optimal for a new member to have these same structural parameter values.     

Banking and the role of money in the business cycle

This paper enriches a standard New Keynesian model with a simple banking sector to investigate the role of money in the business cycle. Maximum likelihood estimation of the model suggests that money balances play a significant role in explaining the intertemporal allocation of consumption and the dynamics of inflation as described by the forward-looking IS and Phillips curves. Nonetheless, the responses of the model’s variables to shocks remain qualitatively similar to a model without money, suggesting that the omission of money balances leaves the model’s transmission mechanism unaffected.     

Simulated Non-Parametric Estimation of Dynamic Models

This paper introduces a new class of parameter estimators for dynamic models, called simulated non-parametric estimators (SNEs). The SNE minimizes appropriate distances between non-parametric conditional (or joint) densities estimated from sample data and non-parametric conditional (or joint) densities estimated from data simulated out of the model of interest. Sample data and model-simulated data are smoothed with the same kernel, which considerably simplifies bandwidth selection for the purpose of implementing the estimator. Furthermore, the SNE displays the same asymptotic efficiency properties as the maximum-likelihood estimator as soon as the model is Markov in the observable variables. The methods introduced in this paper are fairly simple to implement, and possess finite sample properties that are well approximated by the asymptotic theory. We illustrate these features within typical estimation problems that arise in financial economics.     

Shocks,learning, and persistence

A simple model of the process of learning in a diverse economy is presented. This model produces a stylized business cycle with shocks which precipitate the learning process. All agents have the same information, which implies that this business cycle cannot be reduced by improved information flow, counter to many models of output and employment fluctuation.     

A clarification of the IS curve and the aggregate demand curve

This paper clarifies the current textbook interpretations of the IS curve and the aggregate demand (AD) curve. Most macroeconomic textbooks portray the IS curve as representing equilibrium in the product, goods, or commodity market. This paper illustrates that in flexible-price models the IS curve does not necessarily portray equilibrium in the goods market because the textbooks introduce two contradictory notions of equilibrium. Furthermore, it will be shown that, contrary to popular textbook usage, the AD curve, which is derived from the IS-LM framework, is not the economy's effective demand curve for goods.     

A new estimator for trade costs and its small sample properties

This paper discusses the estimation of parameters of a traditional transportation model, as it is typically present in so-called Takayama–Judge type spatial price equilibrium models. In contrast to previously used estimation methods, observations of regional prices as well as of trade costs are used in a direct estimation of the first order conditions. The proposed method uses bi-level programming techniques to minimize a weighted least squares criterion under the restriction that the estimated parameters satisfy the Kuhn–Tucker conditions for an optimal solution of the transport model. A penalty function and a smooth reformulation are used to iteratively approximate the complementary slackness conditions. Monte-Carlo simulations are used to trace out some properties of the estimator and compare it with a traditional calibration method. The analysis shows that the proposed technique estimates prices as well as trade costs more precisely than the traditional calibration method. It is suggested to apply the same method to a range of linear and quadratic models.     

Forecast performance of exchange rate models revisited

This paper re-evaluates the performance of reduced form exchange rate models by updating the Messe-Rogoff study (1983). This paper confirms earlier tests showing that simple monetary models do not perform well, but it finds more positive results for other monetary models that incorporate more dynamic econometric specifications. A simple error correction monetary model out-forecasts a random walk almost half of the time.     

Forecasting economic activity by Bayesian bridge model averaging

This paper proposes the use of Bayesian model averaging (BMA) as an alternative tool to forecast GDP relative to simple bridge models and factor models. BMA is a computationally feasible method that allows us to explore the model space even in the presence of a large set of candidate predictors. We test the performance of BMA in now-casting by means of a recursive experiment for the euro area and the three largest countries. This method allows flexibility in selecting the information set month by month. We find that BMA-based forecasts produce smaller forecast errors than standard bridge model when forecasting GDP in Germany, France and Italy. At the same time, it also performs as well as medium-scale factor models when forecasting Eurozone GDP.     

Empirical determination of aggregate demand and supply curves: The example of the RWI Business Cycle Model

Macroeconometric models are often criticised for being too complex and difficult to read in theoretical terms. To overcome these difficulties, Hickman suggested the calculation of a model's implicit aggregate demand/supply (AD/AS) structure. The method helps to understand models and their main properties in theoretical terms and facilitates detailed model comparisons. This paper uses the AD/AS–IS/LM apparatus to analyse the simulation properties of the RWI (Rheinisch-Westfälisches Institut für Wirtschaftsforschung) Business Cycle Model, a medium-sized short-term macroeconometric model for Germany. The results confirm theoretical expectations for AD and AS elasticities and reveal particular reactions linked to peculiar model specifications such as an endogenous government sector. The results are also much in line with a previous study in a multi-country model context.     

The BMW Model: A New Framework for Teaching Monetary Economics

Abstract: Although the IS/LM-AS/AD model is still the central tool of macroeconomic teaching in most macroeconomic textbooks, it has been criticized by several economists. Colander (1995) demonstrated that the framework is logically inconsistent, Romer (2000) showed that it is unable to deal with a monetary policy that uses the interest rate as its operating target, and Walsh criticized that it is not well suited for an analysis of inflation targeting. The authors present a framework that develops the Romer approach into a very simple but, at the same time, comprehensive macroeconomic model. In spite of its simplicity, it can carry the main insights of the New Keynesian macroeconomics to an intermediate level and deal with issues like inflation targeting, monetary policy rules, and central bank credibility.     

DSGE models,detrending, and the method of moments

One important question in the DSGE literature is whether we should detrend data when estimating the parameters of a DSGE model using the moment method. It has been common in the literature to detrend data in the same way the model is detrended. Doing so works relatively well with linear models, in part because in such cases the information that disappears from the data is usually related to the parameters that also disappear from the detrended model. Unfortunately, in heavy non‐linear DSGE models, parameters rarely disappear from detrended models, but information does disappear from the detrended data. Using a simple real business cycle model, we show that both the moment method estimators of parameters and the estimated responses of endogenous variables to a technological shock can be seriously inaccurate when detrended data are used in the estimation process. Using a dynamic stochastic general equilibrium model and U.S. data, we show that detrending the data before estimating the parameters may result in a seriously misleading response of endogenous variables to monetary shocks. We suggest building the moment conditions using raw data, irrespective of the trend observed in the data.     

Vertical Relationships between Manufacturers and Retailers: Inference with Limited Data

In this paper, different models of vertical relationships between manufacturers and retailers in the supermarket industry are compared. Demand estimates are used to compute price-cost margins for retailers and manufacturers under different supply models when wholesale prices are not observed. The purpose is to identify the set of margins compatible with the margins obtained from estimates of cost and to select the model most consistent with the data among non-nested competing models. The models considered are (1) a simple linear pricing model; (2) a vertically integrated model; and (3) a variety of alternative (strategic) supply scenarios that allow for collusion, non-linear pricing, and strategic behaviour with respect to private label products. Using data on yogurt sold in several stores in a large urban area of the U.S. the results imply that wholesale prices are close to marginal cost and that retailers have pricing power in the vertical chain. This is consistent with non-linear pricing by the manufacturers or high bargaining power of the retailers.