Ching-Chuan Tsong

Investigating the stationarity of insurance premiums: international evidence

This article explores whether there is support for the stationarity hypotheses of life and non-life insurance premiums during the period 1979–2007 for 40 heterogeneous countries. The stationarity of insurance premiums affects insurance companies’ prediction on their future inflow of premium income, which affects the liquidity of insurance companies and their investment plans and thus is relevant to the insurers’ operation. This article employs the advanced nonlinear panel unit-root test with a sequential panel selection method to classify the entire panel into two groups: stationary countries and non-stationary countries. We apply Monte Carlo simulations to derive empirical distributions of the test, which allows us to correct for the finite-sample bias and to consider the cross-country effects. We find relatively stationary life insurance premiums in countries from the following groups: high-income, Europe, and common law origin; relatively stationary non-life insurance premiums exist in the following groups: low-income, Middle East and Africa, and common law origin. Evidence herein shows that different classifications, including income levels, geographic regions, regionally or economically integrated blocs, and legal system, affect the stationarity of life and non-life insurance premiums.

Covariate selection for testing purchasing power parity

This article employs Hansens (1995) Covariate Augmented Dickey–Fuller (CADF) test to reexamine the issue of Purchasing Power Parity (PPP) using post-Bretton Woods exchange rate data for 20 industrialized countries. Instead of just using a single covariate as in the literature, we implement the test by using Bai and Ngs (2002) method to choose suitable stationary covariates. Our empirical results show that the real exchange rates generally display long-run mean reversion and support PPP, as contrasted with those obtained in Amara and Papell (2006) that less rejections of unit root hypothesis are made with the same test. The panel unit root test suggested by Chang (2004) is also performed to justify our results.

TESTING FOR THE EFFICIENT MARKET HYPOTHESIS IN STOCK PRICES: INTERNATIONAL EVIDENCE FROM NONLINEAR HETEROGENEOUS PANELS

Using international data, this paper explores whether the efficient market hypothesis for real stock prices is supported for different panels. The stationarity of a real stock price has important implications for modeling and forecasting financial activities. On a global scale, we implement the recently developed nonlinear heterogeneous panel unit root test, which allows us to account for possible nonlinearity and cross-section dependence and to identify how many and which countries of the panel contain a unit root. The primary conclusion is that the stationarity of real stock prices varies between regions and levels of economic development. Overall, our empirical results illustrate that real stock prices in these countries are a mixture of stationary (integrated of order zero) and nonstationary (integrated of order one) processes.

A REVISIT TO THE STATIONARITY OF OECD INFLATION: EVIDENCE FROM PANEL UNIT‐ROOT TESTS AND THE COVARIATE POINT OPTIMAL TEST*

This paper re‐examines the stationarity of inflation rates in 19 Organisation for Economic Cooperation and Development countries with the use of cross‐sectional information. We employ the panel unit‐root tests that allow for cross‐sectional dependency and the covariate point optimal test. These tests have high power in common due to the exploitation of cross‐sectional information, and they can assist mutually to draw a concrete conclusion on inflation dynamics for all series in the panel. Our empirical results show that allowing for cross‐sectional dependency rejects the null hypothesis that all series in the panel have a unit root, implying that there is at least one stationary series in the panel. With the help of the results of the covariate test, we can distinguish the panel into a group of stationary and a group of non‐stationary series. For robustness, the two groups of series are re‐confirmed by the panel tests. Our results reveal evidence of mean reversion in inflation for 15 of 19 countries, which is significantly stronger as compared to that obtained by the state‐of‐the‐art univariate unit‐root tests.

Further Evidence on Real Interest Rate Equalization: Panel Information, Non‐Linearities and Structural Changes

Previous studies applying traditional unit root tests generally have difficulty providing widespread evidence supporting the real interest rate parity hypothesis (RIPH). This paper aims to analyse the empirical fulfilment of RIPH for 17 OECD countries by employing many recently developed unit root tests. Power of the tests is raised by taking different approaches, such as using cross‐sectional information, accounting for non‐linear adjustment towards the equilibrium and allowing for structural changes. The combined results of the tests using panel information show that broad evidence in favour of RIPH prevails for 13 of the 17 countries. By contrast, univariate tests fail to make widespread rejections of the unit‐root hypothesis. Our evidence reveals a high degree of market integration for developed countries, and the effect of monetary policies as a stabilization tool might be limited at least in the long run.

Do Real Interest Rates Really Contain a Unit Root? More Evidence from a Bootstrap Covariate Unit Root Test

This paper re‐examines the empirical finding that international real interest rates usually have a unit root. This conclusion is put forth in Rapach and Weber (2004), using the Ng and Perron (2001) tests. We use Rudebuschs (1993) approach to construct the small sample distributions of the Ng and Perron tests, and calculate their asymptotic sizes, size‐adjusted powers and rejection rates. These numbers show that the lack of power in the Ng and Perron tests might account for the findings of Rapach and Weber (2004): that the unit root null cannot be rejected for most OECD countries. Size distortions are mild in the case of Ng and Perron tests for two series, but are serious for the Phillips and Perron Z‐test on inflation rates. We then apply a powerful covariate augmented Dickey–Fuller unit root test to examine the series for which stationarity cannot be determined with the Ng and Perron tests. The bootstrap technique is also used to control possible size distortions. In contrast to the results of Rapach and Weber (2004), the bootstrap covariate augmented Dickey–Fuller test yields striking evidence that real interest rates are stationary for 14 of 16 OECD countries, because nominal interest rates are stationary for the 14 countries, while inflation rates are stationary for all countries.

Exchange Rate Pass-Through and Monetary Policy: A Cross-Commodity Analysis

This paper investigates how a change in monetary policy affects the degree and the speed of exchange rate pass-through to import prices in the emerging market economy, using a newly constructed data set from Taiwans trading commodities. First, the analytical framework is set up following Goldberg and Knetter (1997) and Campa and Goldberg (2005). Next, the period-by-period and the multiple-period cumulative effects of monetary policy on the degree of exchange rate pass-through can be traced out. The dynamic panel data model is then estimated by Bun and Carrees (2005) bias-corrected approach, which enjoys easy calculation and robust testing performances, leading to more reliable empirical results. Our cross-commodity evidence strongly supports the partial pass-through in the short run and the complete pass-through in the long run. Moreover, following a change in monetary policy, this pass-through effect increases during several initial periods and declines to zero over time.

BOOTSTRAPPING COVARIATE UNIT ROOT TESTS: AN APPLICATION TO INFLATION RATES

This paper proposes a bootstrap procedure for the covariate point optimal tests (CP) of Elliott and Jansson. Although the covariate tests enjoy large power gains over the traditional univariate unit root tests, our simulations show that they still suffer from severe size distortions at finite samples. Through simulations, we demonstrate the superiority of the bootstrap procedure in the sense that it can yield desirable size and power properties for the CP tests when the Akaikes information criterion is used. Moreover, we show the empirical relevance of the bootstrap tests by applying them to inflation in the G‐10 countries, and then obtain strong evidence against the unit root hypothesis for most countries at the 5% significance level.

Re-examining the Fisher Effect: An Application of Small Sample Distributions of the Covariate Unit Root Test

Abstract This article employs the covariate unit root test proposed by Elliott and Jansson to investigate the stationarity properties of real interest rates. Instead of blindly trusting the asymptotic distribution of the test, we extend Rudebuschs method to estimate its finite sample distributions under the null and alternative hypotheses. With these distributions, we can obtain the probabilities that the test statistic comes from the null and alternative hypotheses, and quantify the asymptotic size as well as the test power for each specific series. Our simulation experiments show that first, due to the higher power raised by the inclusion of covariates, the test can overwhelmingly reject the unit root null for the 16 industrialized countries; secondly, the Ng and Perron tests deliver lower powers in most countries, and thus lead to the false conclusion of non-stationary real interest rates. Finally, allowing for multiple endogenous breaks in the real interest rates provides only stationary evidence in half of the 16 countries.

A revisit on real interest rate parity hypothesis – simulation evidence from efficient unit root tests

A set of unit root tests are applied to test the existence of long-run real interest rate parity among the G-10 countries over the period 1971M1 to 2007M2. Rather than trusting the asymptotic distributions, this article uses simulation techniques to establish the small sample distributions of these tests, conditional on the stationary and nonstationary processes. The empirical results indicate that the tests have stable finite-sample sizes and higher size-adjusted powers such that the two estimated processes can be distinguished from each other. Thus, for six of the nine countries, their series are more likely to come from the estimated Autoregressive (AR) stationary process than from the nonstationary process. Noticeably, the testing results are rather different from those using the asymptotic distributions, in which only three countries support the real interest rate parity.