A study on the subjective symptoms of the ageing process in middle-aged men: effects of socio-economic status,diet and health care behaviour*

In order to investigate the factors influencing the ageing process of middle-aged men, different environmental variables including socio-economic status, diet, smoking and drinking were studied as possible determinants of the ageing process. Six hundred and forty-seven Korean men over 40 years of age were studied. Frequency, chi-square, t-test, and stepwise multiple regression analyses were employed to identify the significant variables. As a result of the analyses, occupation and smoking were found to be the most influential factors. In short, those who did not refrain from smoking and had professional jobs experienced early symptoms in the ageing process.     

A THREE‐STEP PROCEDURE FOR ESTIMATING AND TESTING COINTEGRATED ARMAX MODELS*

To deal with a variety of inferential problems on non‐stationary cointegrated time series, this paper proposes a computationally feasible method based on the Whittle likelihood and examines its performance. For the empirical application of our method, the paper investigates three sets of Japanese and US monetary and financial time‐series data. To evaluate the p‐value of the likelihood ratio statistic, we propose an approximation procedure based on the gamma distribution and the accompanying Laguerre expansion for reducing the computational burden. We also provide a numerical procedure for the asymptotic covariance matrix of the Whittle estimator.     

TESTING THE ONE‐WAY EFFECT IN THE PRESENCE OF TREND BREAKS*

This paper provides an approach to testing the measures of the one‐way effect for cointegrated vector time‐series in the presence of trend breaks. We propose Wald testing the measures and their computational algorithm, an extension of previous work by Hosoya and Yao and Hosoya, to the case where trend breaks are explicitly taken into account in the cointegration relationship. On the basis of the proposed inferential method and the derived evidence, we present a causal structure characterization of money supply and income as well as interest rates for the last 44 years of the Japanese economy, and contrast it with the results of Yao and Hosoya.