Logarithmic spirals are abundantly observed in nature. Gastropods (such as nautilus, cowie, grove snail, thatcher, etc.) in the mollusca phylum have spiral shells, mostly exhibiting logarithmic spirals vividly. Spider webs show a similar pattern. The low-pressure area over Iceland and the...

Theoretical and empirical literature have focused on supply factors when studying economic growth determinants. The present work analyzes demand factors as determinants of the Bolivian economic growth between 1953-2002 using framework introduced by Thirlwall (1979). According to cointegration...

This paper presents an alternative method to the portfolio selection problem. The central hypothesis is that the historical performance of the market can not be ignored. Consequently, we suppose that the price dynamics of any asset will be described by a stochastic differential delay equation:...

This paper reports several entirely new results on financial market dynamics and option pricing We observe that empirical distributions of returns are much better approximated by an exponential distribution than by a Gaussian. This exponential distribution of asset prices can be used to develop...

We investigate the effects of outlier treatment on the estimation of the seasonal component and stochastic models in electricity markets. Typically, electricity spot prices exhibit features like seasonality, mean-reverting behavior, extreme volatility and the occurrence of jumps and spikes....

We study the distributions of the LASSO, SCAD, and thresholding estimators, in finite samples and in the large-sample limit. The asymptotic distributions are derived for both the case where the estimators are tuned to perform consistent model selection and for the case where the estimators are...

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with...

Markov processes are used in a wide range of disciplines, including finance. The transition densities of these processes are often unknown. However, the conditional characteristic functions are more likely to be available, especially for Lévy-driven processes. We propose an empirical likelihood...

This paper proposes a unifying theory of forecasting in the form of a Golden Rule of Forecasting. The Golden Rule is to be conservative. A conservative forecast is consistent with cumulative knowledge about the present and the past. To be conservative, forecasters must seek all knowledge...

A persistent increase in the unemployment rate ignites speculations about whether the changes to unemployment are structural or cyclical. The New Zealand economy has been through major restructuring since the mid-1980s. The labour market’s institutional changes were the last in the sequence of...