Wilson study cycles: Research relative to ocean geodynamic cycles

The effects of conversion of Atlantic (rifted) margins to convergent plate boundaries; oceanic plateaus at subduction zones; continental collision and tectonic escape; southern Africa rifts; and global hot spot distribution on long term development of the continental lithosphere were studied

Evidence and Ideology in Macroeconomics: The Case of Investment Cycles

The paper reports the principal findings of a long term research project on the description and explanation of business cycles. The research strongly confirmed the older view that business cycles have large systematic components that take the form of investment cycles. These quasi-periodic movements can be represented as low order, stochastic, dynamic processes with complex eigenvalues. Specifically, there is a fixed investment cycle of about 8 years and an inventory cycle of about 4 years. Maximum entropy spectral analysis was employed for the description of the cycles and continuous time econometrics for the explanatory models. The central explanatory mechanism is the second order accelerator, which incorporates adjustment costs both in relation to the capital stock and the rate of investment. By means of parametric resonance it was possible to show, both theoretically and empirically how cycles aggregate from the micro to the macro level. The same mathematical tool was also used to explain the international convergence of cycles. I argue that the theory of investment cycles was abandoned for ideological, not for evidential reasons. Methodological issues are also discussed

Life Cycle and Cohort Productivity in Economic Research: The Case of Germany

We examine the research productivity of German academic economists over their life cycles. It turns out that the career-patterns of research productivity as measured by journal publications are characterized by marked cohort effects. Moreover, the life-cycles of younger German economists are hump-shaped and closely resemble the life cycles identified for U.S. economists, whereas the life-cycles of older German economists are much flatter. Finally, we find that not only productivity, but also research quality follows distinct life cycles. Our study employs econometric techniques that are likely to produce estimates that are more trustworthy than previous estimates.research productivity, life cycles, cohort effects

INTERNATIONAL TRANSMISSION OF BUSINESS CYCLES. ESRI Research Bulletin 2010/3/2

Increased international economic integration over the past two decades has stimulated a growing academic and policy interest in the analysis of the international transmission of business cycles. There has been renewed interest recently in this research topic notably in relation to the current global financial and economic crisis. In an increasingly integrated world economy, understanding the extent to which business cycles propagate across countries and regions and their underlying factors is highly important to investors and policy makers. Furthermore, in the case of monetary unions, business cycle synchronisation is taken as an indication of a low probability of asymmetric shocks and so of a low cost of losing independence over monetary and exchange rate policies

'But I thought we were friends?' Life cycles and research relationships

This chapter is concerned with a relatively under-explored aspect of ‘engaged research’ – the nature of friendship relations between researchers and practitioners, and the ethical dilemmas that arise in such relationships. Attention has been paid to the relational aspects of research in the methodology literature, but this chapter focuses more closely on friendship in particular. The chapter is framed around two guiding concerns: how do friendships, formed in and around research, change over time; and in view of friendship conceived in this dynamic fashion, what ethical questions and dilemmas arise for the ‘friends’

A Comment on "Cycles and Instability in a Rock-Paper-Scissors Population Game: A Continuous Time Experiment"

The authors (Cason, Friedman and Hopkins, Reviews of Economics Studies, 2014) claimed a result that the treatments (using simultaneous matching in discrete time) replicate previous results that exhibit weak or no cycles. After correct two mathematical mistakes in their cycles tripwire algorithm, we research the cycles by scanning the tripwire in the full strategy space of the games and we find significant cycles missed by the authors. So we suggest that, all of the treatments (using simultaneous matching in discrete time) exhibit significant cycles.Comment: 2 pages, Keywords: experiments, cycles, mixed equilibrium, discrete time. JEL numbers: C72, C73, C92, D8

Temporal relations between mineral deposits and global tectonic cycles

Natural Environment Research Council (grant NE/J021822/1) supported this research.Mineral deposits are heterogeneously distributed in both space and time, with variations reflecting tectonic setting, evolving environmental conditions, as in the atmosphere and hydrosphere, and secular changes in the Earth’s thermal history. The distribution of deposit types whose settings are tied to plate margin processes (e.g. orogenic gold, volcanic-hosted massive sulphide, Mississippi valley type Pb–Zn deposits) correlates well with the supercontinent cycle, whereas deposits related to intra-cratonic settings and mantle-driven igneous events, such as Ni–Cu–PGE deposits, lack a clear association. The episodic distribution of deposits tied to the supercontinent cycle is accentuated by selective preservation and biasing of rock units and events during supercontinent assembly, a process that encases the deposit within the assembled supercontinent and isolates it from subsequent removal and recycling at plate margins.Publisher PD

Convex Cycle Bases

Convex cycles play a role e.g. in the context of product graphs. We introduce convex cycle bases and describe a polynomial-time algorithm that recognizes whether a given graph has a convex cycle basis and provides an explicit construction in the positive case. Relations between convex cycles bases and other types of cycles bases are discussed. In particular we show that if G has a unique minimal cycle bases, this basis is convex. Furthermore, we characterize a class of graphs with convex cycles bases that includes partial cubes and hence median graphs. (authors' abstract)Series: Research Report Series / Department of Statistics and Mathematic