The permanent income hypothesis: A new framework based on fractional integration and cointegration

The issue of the Permanent Income Hypothesis (PIH) is revisited in this paper by examining the relationship between U.S. consumption and income through new statistical techniques based on fractional integration and cointegration. Using a procedure by Robinson [1994a] that permits the testing of I(d) statistical models, the results show that both individual series are I(1). However, the differences seem to be I(d), with d being smaller than 1 in some cases. Also, when performing different regressions of consumption on income, the estimated residuals from the cointegrating regressions appear to be mean reverting. This implies that consumption and income may be fractionally cointegrated, so that deviations from equilibrium are highly persistent. Thus, the results provide further evidence regarding the validity of the PIH for the U.S.The author gratefully acknowledges the comments from an anonymous referee. Financial support from the Minsterio de Ciencia y Technologia (SEC2002-01839, Spain) is also acknowledged.     

Tests for cointegration with two unknown regime shifts with an application to financial market integration

It is widely agreed in empirical studies that allowing for potential structural change in economic processes is an important issue. In existing literature, tests for cointegration between time series data allow for one regime shift. This paper extends three residual-based test statistics for cointegration to the cases that take into account two possible regime shifts. The timing of each shift is unknown a priori and it is determined endogenously. The distributions of the tests are non-standard. We generate new critical values via simulation methods. The size and power properties of these test statistics are evaluated through Monte Carlo simulations, which show the tests have small size distortions and very good power properties. The test methods introduced in this paper are applied to determine whether the financial markets in the US and the UK are integrated.      

Instability in cointegration regressions: a brief review with an application to money demand in Portugal

This study addresses some modelling questions related to the possibility of structural change in models with nonstationary variables. Focusing on cointegration issues, some methodological aspects are discussed, attempting to integrate coherently the several steps of the modelling strategy. These range from unit root to cointegration testing and to testing for instability in the cointegration vector. An empirical example with Portuguese data tries to illustrate the usefulness of this approach, where a simple money demand function is estimated using an error-correction model (ECM). If a break is explicitly allowed in the cointegration vector the forecasting performance of the ECM improves.     

Modelling UK house prices using cointegration: an application of the Johansen technique

This paper provides an econometric analysis of the long-term equilibrium determination of UK house prices using the relatively recent Johansen cointegration procedure. This long-term equilibrium specification is then utilized in order to estimate a parsimonious dynamic model for UK house prices.     

Bayesian cost-effectiveness analysis for censored data: an application to antiplatelet therapy

Abstract

Objective:

Cost-effectiveness analysis (CEA) on trial-based data has played an important role in pharmacoeconomics. A regression model can be used to account for patient-level heterogeneity throughout covariates adjustment in CEA. However, the estimates from CEA could be biased if ignoring the censoring issue on effectiveness and costs. This study is to propose a regression model to account for both time-to-event effectiveness and cost.

Methods:

A bivariate regression model was proposed to analyze both effectiveness and cost simultaneously, while censored observations were also taken into account. The regression coefficients were estimated using a Bayesian approach by drawing a random sample from their posterior distribution derived from the Markov chain Monte Carlo (MCMC) method. The proposed method was illustrated using empirical data of anti-platelet therapies to the management of cardiovascular diseases for those patients with high risk of gastrointestinal (GI) bleeding, where cost-effectiveness between different therapies was analyzed under both censored and non-censored circumstances, where the effectiveness was defined as the time to re-hospitalization due to GI complications, and the cost was measured by the total drug expenditure.

Results:

Under censored circumstances, aspirin plus proton-pump inhibitors (PPIs) was considered more cost-effective than clopidogrel with/without PPIs, as shown in the cost-effectiveness acceptability curve, and clopidogrel was preferred to aspirin for a willingness-to-pay of 89 NTD for delaying 1 day to hospitalization due to GI complications.

Conclusions:

Ignoring censoring problems could possibly bias the results in CEA. This study has provided an appropriate method to conduct regression-based CEA to improve the estimation which serves its purpose for CEA concerns.

Limitations:

The normality assumption for the cost and effectiveness in the bivariate normal regression needs to be examined, and the conclusions may be biased if this assumption is violated. However, when sample size is sufficiently large, a slight deviation from normality would not be a serious problem.     

A simple method of estimating interest elasticities from survey data

A technique similar to that used by Carlson and Parkin (1975) is developed to estimate interest rate elasticities of demand for financial assets. A numerical example is given.     

Producer price adjustment to commodity price shocks: An application of threshold cointegration

During the 1980s and 1990s, most developing countries in Sub-Saharan Africa and Latin America implemented structural adjustment reforms, which included the liberalization of export crop markets and the abolition of marketing boards. The emergence of new marketing systems may have altered price transmission mechanisms, especially if collusion behaviors have appeared among domestic stakeholders along the marketing chain. I use threshold cointegration tools to analyze the dynamics of world price transmission to coffee growers in three deregulated markets. The methods I use allow me to test the presence of a threshold in both the cointegrating relationship and its corresponding error correction model. Over the pre-reform period, I detect asymmetric price adjustments that appear favorable to producers - deviations from the long-run equilibrium resulting from largest increases in world prices being eliminated relatively quickly - and disappear in the post-reform period. On the contrary over the post-reform period, the results suggest that largest decreases in world prices may be transmitted relatively quickly to growers. These results can be seen as expressions of a favorable pricing policy over the pre-reform period and an unfavorable influence of new private agents over the post-reform period, meaning that in some cases reforms may have failed to create competitive market structures.     

Remittances and output in Bangladesh: an ARDL bounds testing approach to cointegration

Although the relationship between remittances and output is still inconclusive in literature, most studies find that remittances have a positive effect on output in the long run. Contrary to this conventional direction of causality from remittances to output, our study finds that output alone determined long-run movements in remittances in a positive direction in the Bangladesh economy over the last 35 years from 1976 to 2010. We use the autoregressive distributive lag (ARDL) bounds testing approach to cointegration to explore this long-run relationship. Surprisingly, remittances do not appear to be a long-run forcing variable to the explanation of Bangladesh’s output over the same period. While examining the channels of this output–remittance mechanism remains an area of research for the future, we hypothesize that the rise in remittances in response to increased income occurs through higher import demand and greater investment opportunities. This finding implies that Bangladeshi policymakers can influence remittances through national output in the long run.     

Goodness-of-fit techniques for count data models: an application to the demand for dental care in Spain

This paper compares the practical performance of alternative goodness-of-fit techniques for count data models in the context of a study of the determinants of demand for dental care in Spain. We apply alternative goodness-of-fit techniques to different specifications. In particular, we implement recently proposed specification tests which are consistent in the direction of general nonparametric alternatives. The analysis suggests that a negative binomial model is an appropriate specification for dental care demand. Dental health and income are identified as important predictors of individuals' behavior. First version received: April 2000/Final version received: March 2001     

On the application of the rank tests for nonlinear cointegration to PPP: The case of Papua New Guinea

Much interest has been paid recently to the nonlinear cointegrating relations existing among economic variables. Various testing procedures are already available to test for the existence of nonlinear cointegration. For example, Breitung (2001) proposes rank tests and his testing procedure has been broadly applied. In this study, we warn against a blind application of the rank cointegration tests, particularly to economic variables that evidence certain behavior. As an illustration, we employ the nominal exchange rates and relative prices of Papua New Guinea against her major trading partners with the objective of testing the validity of purchasing power parity for the country. Our simulation results also confirm our warnings. Additionally, we provide some simple solutions to the problem we encounter herein.     

Demand for cigarettes in Turkey: an application of count data models

Household cigarette demand in Turkey is examined using the zero-inflated negative binomial model to account for a large portion of households not reporting cigarette smoking or purchase and estimated using the data from the national household survey implemented in 2003. Data were divided into two main groups: families with and without teenagers. Results identify relevant household head and household characteristics needed to develop effective public policy to prevent the decision to begin to smoke and to reduce cigarette purchase to lower the future growth of government healthcare expenditures. Specifically, healthcare expenditure share, income, and cigarette-price elasticities are relevant in lowering cigarette purchases. The calculated price elasticities for cigarette demand falls within the range determined by studies conducted for developed countries including the member states of the European Union. An estimate of the effect of an increase in the excise tax lowering demand is provided.     

Spatial shift-share analysis versus spatial filtering: an application to Spanish employment data

The aim of this work is to analyse the influence of spatial effects in the evolution of regional employment, thus improving the explanation of the existing differences. With this aim, two non-parametric techniques are proposed: spatial shift-share analysis and spatial filtering. Spatial shift-share models based on previously defined spatial weights matrix allow the identification and estimation of the spatial effects. Furthermore, spatial filtering techniques can be used in order to remove the effects of spatial correlation, thus allowing the decomposition of the employment variation into two components, respectively related to the spatial and structural effects. The application of both techniques to the spatial analysis of regional employment in Spain leads to some interesting findings and shows the main advantages and limitations of each of the considered procedures, together with the quantification of their sensitivity with regard to the considered weights matrix.     

Nontradable goods prices and per-caita income: an application to regional Korean data

A system of demand equations (given oligopolistic interdependence amon firms) is derived and estimated for two four-digit SIC code industries to explain firms' R&D behaviour through time. The two industries chosen are the perfume, cosmetic and toiletries (PCT) industry, and the drug industry. The industries chosen belong to the same two-digit SIC code classification called the Cchemical and Allied Products industry but not in the drug industry. The introduction of the R&D tax credit in 1981, however, reduced the tendency to free-ride in both industries.     

Decomposition analysis of consumers' demand changes: an application to Greek consumption data

A decomposition analysis for consumer demand functions is developed. Changes in Marshallian demand or expenditure shares functions over time are decomposed into a total substitution effect, an income effect, and a habit effect. This framework is applied to post-war Greek consumption patterns through a habit persistence version of the Quadratic Almost Ideal Demand System (QUAIDS). It is found that for all commodity categories (i.e., food, beverages and tobacco, footwear and clothing, settling and housing, and others) the income effect was the main driving force in explaining changes in both quantity demanded and expenditure shares, followed by habit and total substitution effects.     

The U.S. trade imbalance and real exchange rate: An application of the heterogeneous panel cointegration method

The United States economy suffers from persistent trade deficits, arising from the so-called ‘global external imbalance’. Can the depreciation of the US dollar improve this phenomenon? This study for the first time applies the heterogeneous panel cointegration method to examine the long-run relationship between the real exchange rate and bilateral trade balance of the U.S. and her 97 trading partners for the period 1973–2006. Using new annual data, the empirical results indicate that the devaluation of the US dollar deteriorates her bilateral trade balance with 13 trading partners, but improves it with 37 trading partners, especially for China. In the panel cointegrated framework, a long-run negative relationship between the real exchange rate and the bilateral trade balance exists for the U.S.     

Non-linear cointegration and adjustment: an asymmetric exponential smooth-transition model for US interest rates

This paper seeks to extend the extant empirical evidence regarding asymmetric adjustment to equilibrium of short and long interest rates. Using an adaptation of the exponential smooth transition model to allow for sign asymmetry in the transition function, we show that equilibrium reversion exhibits two broad characteristics. First, small deviations are random, while large deviations are reverting. Second, deviations that arise when the long rate exceeds the short rate are characterised by quicker reversion than the opposite case. These results are consistent with the effects of arbitrage and central bank intervention. Finally, forecasting exercises support this model over alternate linear and non-linear specifications.      

A new test for deficit sustainability and its application to US data

In this paper, we define deficit sustainability by requiring formally that both the discounted debt vanish asymptotically and the undiscounted debt be bounded. Thus, a new necessary condition and a new testing procedure emerge. We propose a new test statistic and prove that its limiting distribution is standard normal, N(0, 1). Its finite- sample distribution differs from N(0, 1), however, mainly because it has fat tails, so we derive empirical critical values using simulations. Using the new test and United States (US) quarterly data, the conclusions of three earlier papers that fail to reject the sustainability of the US budget or current-account deficit are reversed.     

Estimating exchange rate dynamics with diffusion processes: an application to Greek EMU data

Recently various exchange rate models capturing the dynamics during the transition from an exchange rate arrangement of floating rates into a currency union have been derived. Technically, these stochastic equilibrium models are diffusion processes which have to be estimated by discretely sampled observations. Using daily exchange rate data prior to the Greek EMU-entrance on 1 January 2001, we develop a rigorous estimation procedure. Our estimates point to an increasing interventionist economic policy in the run-up to the Greek EMU entrance. A comparison of this econometric indication with policy information provided (ex-post) by the Bank of Greece (BoG) in its Annual Report 2000 reveals that the BoG indeed pursued such an active policy stance (so-called institutional frontloading strategies).      

Using real-time electricity data to estimate response to time-of-use and flat rates: an application to emissions

Using a generalized McFadden specification, we estimate the determinants of hourly response for the years 2006 through 2010 for all 16 standard retail customers who were on an optional real-time electricity rate offered by Duke Energy as of 2010, and provide a method to estimate how these customers would respond to time-of-use (TOU) and flat rates. We generalize the model to allow for inter-day response, as well as threshold prices, above which individual customer response may increase or decrease. With these inclusions, we find hourly elasticity for the group of customers to be as large as ?0.7, larger than previous studies. We apply the method to examine a recent finding that time-differentiated rates could increase electric utility emissions. However, that result did not differentiate between real-time and TOU rates, and furthermore held energy use constant in comparing flat rates and time-differentiated rates. We perform a case study to examine emissions of SO₂, NOx, Hg, and CO₂ based on predicted energy use changes as well as for an energy-neutral case for real-time, TOU and flat rates. Employing energy use predictions from the model, increased energy use results in increased emissions in almost all cases. For the energy-neutral case, time-differentiated rates increase CO₂ as compared to flat rates, and the TOU rate causes a larger increase than does real-time pricing. But both rates decrease other emissions in the majority of years, particularly SO₂ In addition, time-differentiated rates reduce NOx potency by shifting it to non-daylight hours when conditions for the formation of smog are less favorable. Our application leads to the conclusion that the effect of the rates on emissions must consider total energy use as well as the shift from peak to off-peak. Furthermore, the predictions require consideration of the generating mix at a more detailed level than was contained in previous studies.