Consequences of Hodrick–Prescott filtering for parameter estimation in a structural model of inventory behaviour

Much work in macroeconomics relies on detrending a time series prior to analysis. A popular method of detrending has been the Hodrick–Prescott (HP) filter. This filter has been widely applied in the Real Business Cycle literature to isolate the behaviour of economic variables at business cycle frequencies and to look at comovements between series over the business cycle. Prior work has shown that the use of this filter can have serious consequences for such analysis, such as inducing spurious correlations, and that a researcher should proceed with caution when applying the filter. Another use of HP filtering has been to achieve stationarity prior to estimation of structural econometric models. Little work has been done concerning the possible effects this method of detrending may have on parameter estimation from such models. Given the problems with the filter noted in the literature, it is likely these effects may be of some consequence to estimation results. Using a common model of inventory behaviour, a simulation study is conducted to assess the impact of using the HP filter for detrending prior to estimation. A comparison will be made to other methods of handling trend to gauge relative performance.     

A model of trust in quality and North–South trade

Why do some countries produce higher quality goods than other countries? This paper suggests that one reason is self-perpetuating reputations, modelling the idea with a Klein–Leffler reputation model embedded in a general equilibrium model of trade. Reputation differences are particularly interesting because reputation is a form of “social capital”. Like product differentiation, it can explain why countries might trade even if their technologies and endowments are identical, why firms could profit from exports even if the foreign price is no higher than the domestic one, and why governments like to have “high-value” sectors. Ideally, a developing country would shift its own producers to a high-quality equilibrium; if that is not possible, the next best thing is to import experience goods and substitute to home production of goods for which reputation is not important.     

Predicting the competitive relationships of industrial production between Taiwan and China using Lotka–Volterra model

This work is the first to apply Lotka–Volterra model combined with genetic algorithm (GA) to predict the production relationships of high-tech industry among different areas. Previous studies analysed the trade interdependency among various countries, but few studies have highlighted the quantitative evidence of production relationships. Thus, this study utilizes motherboard shipment volumes to predict the competitive relationships of industrial production on both sides of the Taiwan Strait. Specifically, this work uses simultaneous non-linear least square regression in combination with GAs for numerical parameter optimization of the proposed Lotka–Volterra model. The results of parameter estimation reveal that shipment growth in China substantially promotes that in Taiwan, whereas the shipment growth in Taiwan curtails that in China. The standard deviation of the estimated parameters from the 3000 iterated simulations is small, confirming the reliability and stability of our parameter estimations. According to equilibrium analysis, the results of Lyapunov function prove that the shipments of China and Taiwan will reach a stable long-term equilibrium. The potential production from China will ultimately be nearly 16 times as large as that from Taiwan. Finally, the analytical results of forecast accuracy confirm that Lotka–Volterra model performs better than conventional S-curve diffusion model in predicting motherboard shipments.     

A model for measuring and ranking a firm’s patent portfolio

ABSTRACT

Patent quality (PQ) is a critical and complex factor of a firm’s patent strategy. We posit that the existing PQ models and their methodological approaches are limited in their ability to address the multiple priorities of PQ – a firm’s strategic intentions, its stakeholders and balancing technology superiority and legal validity. We advance PQ literature by identifying the fourth generation of strategic PQ indicators and propose a hybrid multi-criteria model, based on AHP–TOPSIS, for patent portfolio measurement. The proposed PQ model provides a simple template that can guide the decisions of patent managers pursuing high quality patent portfolios. We test the PQ model by applying it in two sectors: 3G WCDMA telecommunications and biotechnology.     

Monetary–fiscal policy interaction and fiscal inflation: A tale of three countries

We study the impact of the interaction between fiscal and monetary policy on the low-frequency relationship between the fiscal stance and inflation using cross-country data from 1965 to 1999. In a first step, we contrast the monetary–fiscal narrative for Germany, the U.S., and Italy with evidence obtained from simple regression models and a time-varying VAR. We find that the low-frequency relationship between the fiscal stance and inflation is low during periods of an independent central bank and responsible fiscal policy and more pronounced in times of non-responsible fiscal policy and accommodative monetary authorities. In a second step, we use an estimated DSGE model to interpret the low-frequency measure structurally and to illustrate the mechanisms through which fiscal actions affect inflation in the long run. The findings from the DSGE model suggest that switches in the monetary–fiscal policy interaction and accompanying variations in the propagation of structural shocks can well account for changes in the low-frequency relationship between the fiscal stance and inflation.     

A two-country dynamic Heckscher–Ohlin model with physical and human capital accumulation

We study a two-country endogenous growth model in which the long-run growth is propelled by the accumulation of physical and human capital. We show that in the integrated world economy, there exists a unique and locally saddlepoint stable balanced growth equilibrium. We also show that the incorporation of adjustment costs in the process of human capital accumulation leads to a lower long-run growth rate. We then show that, in the 2-country world economy with international trade, balanced growth is possible. Finally, we present a dynamic Heckscher–Ohlin theorem concerning the pattern of international trade. We appreciate the constructive comments from an anonymous referee which have improved this paper significantly. We acknowledge also with gratitude the valuable comments of Hideyuki Adachi, Kosuke Aoki, Daniel Bernhofen, Eric Bond, Koichi Futagami, Ronald Jones, Tamotsu Nakamura and Raymond Riezman on earlier versions. We appreciate also the beneficial comments from the participants of the GEP conference on New Directions in International Trade Theory held in the University of Nottingham and of the Adachi OB Workshop in Kobe University.     

The Feldstein–Horioka model re-visited for African countries

We study the relationship between the saving and investment rates for 20 African countries using a long period of data. A high correlation between saving and investment is often taken as evidence of capital immobility. We use the new Ng–Perron unit root tests to examine the stationarity of saving and investment rates. Both Johansen cointegration tests and fractional cointegration tests are used. The results are mixed. The Johansen cointegration tests show that the saving and investment rates are cointegrated only for Rwanda and South Africa. This implies that for the other 18 countries, there is evidence of capital mobility. The fractional cointegration test results are different. The two rates are found to be fractionally cointegrated for the following 12 countries: Algeria, Burundi, Egypt, Morocco, Niger, Rwanda, Senegal, South Africa, Swaziland, Tunisia, Tanzania and Zimbabwe. For Cote d’Ivoire, Kenya, Lesotho and Sierra Leone there is some evidence of capital mobility while the results for Ethiopia, Malawi, Mauritius and Nigeria are mixed.     

Trends in compensation for production workers: 1948–1995

Between 1977 and 1995, real after-tax hourly compensation for production workers fell by almost 14 percent. Both real pre-tax wages and the real value of benefits fell over this period. These estimates were generated using a cost-of-living index that was adjusted for a wide range of upward and downward biases     

A copula–GARCH model for macro asset allocation of a portfolio with commodities

Many authors have suggested that the mean-variance criterion, conceived by Markowitz (The Journal of Finance 7(1):77–91, 1952), is not optimal for asset allocation, because the investor expected utility function is better proxied by a function that uses higher moments and because returns are distributed in a non-Normal way, being asymmetric and/or leptokurtic, so the mean-variance criterion cannot correctly proxy the expected utility with non-Normal returns. In Riccetti (The use of copulas in asset allocation: when and how a copula model can be useful? LAP Lambert, Saarbrücken 2010), a copula–GARCH model is applied and it is found that copulas are not useful for choosing among stock indices, but can be useful in a macro asset allocation model, that is, for choosing stock and bond composition of portfolios. In this paper I apply that copula–GARCH model for the macro asset allocation of portfolios containing a commodity component. I find that the copula model appears to be useful and better than the mean-variance one for the macro asset allocation also in presence of a commodity index, even if it is not better than GARCH models on independent univariate series, probably because of the low correlation of the commodity index returns to the stock, the bond and the exchange rate returns.     

Black–white wage differentials: duration and probability unemployment effects in a multiple of sample selection bias model

The extent to which probability and duration of unemployment affect the black–white wage differentials is examined in this paper. The paper simultaneously incorporates in the wage equation the multiple sample selection bias that occurs as a result of individuals’ propensity to be in the labor force, and the firm’s hiring decisions. The results reveal a substantial contribution of the duration of unemployment variable to the black–white wage differential, but a small portion of the differential is explained by the probability of unemployment. The results also indicate a sizeable difference between the contribution of the duration of unemployment variable to the male’s wage differentials (26%) and to the female’s (35%). The study finds that an individual’s labor force decision as well as a firm’s hiring decision are important in the wage determination process and that failure to account for the sample selectivity bias due to these two decisions will result in either underestimating or overestimating the wage differentials between black and white workers. At the macro level, the results seem to suggest that promotion of racial wage equality should be associated with policies that will minimize blacks’ incidence of unemployment and duration of unemployment spells.     

A model of exchange rate policy: evidence for the US dollar–Greek drachma rate 1975–87

This paper represents an attempt to model movements of the exchange rate between the US dollar and Greek drachma. A stuctural model is set up, and then a reduced-form error correction(EC) speicifcation is derived. On the basis of co-integration test, the results do not support the existence of al long-run equilibrium relationship between the exchange rate and price differential. Furthermore, the instrumental variable estimation of the EC model indicates that the monetary authorities have pursued a short-run anti-inflationary exchange rate poilicy that appreciates the exchange rate in the presence of wage inflation as an attempt to mitigate the depreciating pressures on the domestic currency and thus to ease the adjustment required on Greek producers.     

A model of techno-economic evaluation for eco-industrial park project

An eco-industrial park or estate is a community of manufactaring and service businesses located together on a common property. The goat of ElP is to create a win-win harmonious development aspect of ecooomic development and environmental protection. This paper emphasizes that the external .effect of an EIP is its main characteristic of technoeconomic evaluation for eco-industrial park project. From the view of the property, rights, the EIP＇s product is typicalty public-private. The government should take some inca.rares for the quantitative analysis on ecological positive externalities of the enterprises in EIP, and also should adopt Coase＇s Theorem, which supports that the market transaction is the best way to deal with positive externalities （external economics or diseconoraics）, or Pigou＇s Theorem, which holds that the government anti-positive externalities programs are the best way to cope with positive externalities, to internalize the EIP＇s external effects, which is also a fundamental tool to encourage investors to actively invest in EIP projects, Furthermore. this paper thinks that the EIP ＇s income should be equal to the income of staple products of the private property, and that of its by-products of the public property. According to this principle, this paper has put forward three major indicators, net present value （NPV）, internal rate of renan （IRR）, and investment repayment period （IRP）, which are also extensively used indicators in ardinary project techno-economic evaluation model to evaluate EIP technoeconomic effects. Theoretically, the indicatory not only can be used in EIP project evaluation, but also can provide a quantitative measure toot for the government to support EIP＇s construction to the maximum. In the end. a case is analyzed.     

Industrial invention: a supply and demand model for the UK, 1961–1989

A supply and demand model of industrial invention is presented paying particular attention to the impact of past advances on present advances in knowledge. The model is estimated using a recent span of UK data: a good fitting specification is found, which passes a battery of diagnostic tests, and possesses sensible long-run properties and an interpretable lag structure. The specific results found should be of potential interest to governments wishing to encourage the flow of inventions by fiscal means.     

A monetary model of China–US trade relations

This paper develops a general equilibrium monetary model to study China–US trade relations. The model captures two main features of China–US trade: China's fixed exchange rate regime and the use of the US dollar as the international medium of exchange. The main conclusions of this paper are threefold. First, an improvement in the productivity of China's tradable sector would benefit both China and the US. Second, a RMB appreciation would reduce consumption in the US and increase consumption in China, and would likely reduce China's trade surplus. It would also lead to a contraction in China's tradable sector and an expansion in US's tradable sector. Third, a monetary expansion in the US would hurt China because it would lead to a transfer of wealth from China to the US, a fall in China's relative wage rate and terms of trade, and an artificial expansion in China's tradable sector. A US monetary expansion would also increase China's trade surplus.     

A characterization of the coskewness–cokurtosis pricing model

The coskewness–cokurtosis pricing model is equivalent to absence of any positive-alpha return for which the residual risk has positive coskewness and negative cokurtosis with the market. This parallels the CAPM and also the fundamental theorem of asset pricing.     

A grey dynamic model for the evaluation of regional sustainable development and its empirical study

Currently, traditional development issues, such as economic stagnation, as well as new challenges like environmental degradation and globalization, need attention. Sustainable development, including economic, environmental, and social elements, is a main goal of decision-makers. The key to sustainable decision-making is to evaluate and forecast the status quo of sustainable development. Policy makers need a tool based on scientific information to forecast the effects of future actions on sustainability and make policies for sustainable development. This paper analyzes the relation of the economy, environment and social welfare by the grey dynamic model. The proposed method uses time series and basic indicators of ecological system, including economic, environmental and social sub-systems. It is applied to Heilongjiang Province and Jiangsu Province. The results have proved different status quo of sustainable development in these two regions, and suggestions are proposed, such as optimization of industrial structure and eco-industrial development. The conclusion is that there is no unique sustainable path, and accordingly, policy makers should choose different criteria and strategies to make efficient sustainable decisions for each region.     

A generalization of the Cairns–Krautkraemer model and the optimality of the mining rule

There exists a rule of thumb of mines, which decides how the cut-off grade (the lowest grade of extracted ore) should change in response to a change in the price of the metal. It requires that the cut-off grade should decrease (increase) when the present value price of metal increases (decreases). In this paper, the optimality of the rule will be examined by generalizing the Cairns–Krautkraemer model under the perfect foresight assumption.     

Evolutionary competition between prediction rules and the emergence of business cycles within Metzler’s inventory model

We revise Metzler??s well-known inventory model by developing a framework in which producers can either apply a simple but cheap extrapolative or a more sophisticated but expensive regressive forecasting rule to predict future sales. Producers are boundedly rational in the sense that they tend to select forecasting rules with a high evolutionary fitness. Using a mixture of analytical and numerical tools, we attempt to describe the characteristics of our model??s dynamical system. Our results suggest that the evolutionary competition between heterogeneous predictors may lead to irregular fluctuations in economic activity.