In this short note, we prove by an appropriate change of variables that the SVI implied volatility parameterization presented in Gatheral's book and the large-time asymptotic of the Heston implied volatility agree algebraically, thus confirming a conjecture from Gatheral as well as providing a...

We study some measurement issues that arise when analyzing the long run behavior of the jth creative region's time t log output per creative class member (y_j(t)) when this region is part of an aggregate economy of j = 1, …, N creative regions. We focus first (second) on absolute (relative)...

We study some measurement issues that arise when analyzing the long run behavior of the jth creative region's time t log output per creative class member (y_j (t)) when this region is part of an aggregate economy of j=1,…,N creative regions. We focus first (second) on absolute (relative)...

In many applications common in testing for convergence the number of cross-sectional units is large and the number of time periods are few. In these situations asymptotic tests based on an omnibus null hypothesis are characterised by a number of problems. In this paper we propose a multiple...

Since the early 1990s, there has been a renaissance in the study of regional growth, spurred by new models, methods, and data. We survey a range of modeling traditions, and some formal approaches to the hard problem of regional economics; namely, the joint consideration of agglomeration and...

This paper introduces a model of localised competition and technological adoption that produces interesting geographical adoption patterns: Persistent asymmetry, where nobody adopts, Leapfrogging where only followers adopt, Forging ahead where only leaders adopt and Catching up where everybody...

In this paper an attempt is made to assess the hypothesis of re- gional club-convergence, using a spatial panel analysis combined with B-Splines. In this context, a 'convergence-club' is conceived as a group of regions that in the long-run move towards steady-state equilib- rium, approximated in...

A new urban revolution begun in the second half of the XX century and it is going to challenge the relation between the size and economic role of cities: on one side, the last decades have witnessed the emergence and the never seen growth of a number of Mega-cities, with more than 9 million...