A statistical physics perspective on criticality in financial markets

Stock markets are complex systems exhibiting collective phenomena and particular features such as synchronization, fluctuations distributed as power-laws, non-random structures and similarity to neural networks. Such specific properties suggest that markets operate at a very special point. Financial markets are believed to be critical by analogy to physical systems but few statistically founded evidence have been given. Through a data-based methodology and comparison to simulations inspired by statistical physics of complex systems, we show that the Dow Jones and indices sets are not rigorously critical. However, financial systems are closer to the criticality in the crash neighborhood.Comment: 23 pages, 19 figure

Fearless Friday: Taylor Bury

This week, SURGE is pleased to feature Taylor Bury ’16 as Gettysburg’s Fearless Leader! Taylor is a senior at Gettysburg College. She is a Biology Major from York, Pennsylvania. She has been involved with Student Senate since her first year on campus, rising through the ranks to serve as its President. [excerpt

Lagrangian and spectral analysis of the forced flow past a circular cylinder using pulsed tangential jets

We numerically investigate the influence of pulsed tangential jets on the flow past a circular cylinder. To this end a spectral-Lagrangian dual approach is completed on the basis of time-series data. The analysis reveals that the flow response to unsteady for- cing is driven by strong interactions between shear layers and pulsed jets. The latter preferentially lead to either the lock-on regime or the quasi-steady vortex feeding regime whether the excitation frequency is of the order of, or significantly greater than the fre- quency of the natural instability. The intensity of the wake vortices is mainly influenced by the momentum coefficient through the introduction of opposite-sign vorticity in the shear layers. This feature is emphasized using a modal-based time reconstruction, i.e. by reconstructing the flow field upon a specific harmonic spectrum associated with a charac- teristic time-scale. The quasi-steady regime exhibits small-scale counter-rotating vortices that circumscribe the separated region. In the lock-on regime, atypical wake patterns as 2P or P+S can be observed, depending on the forcing frequency and the momentum coefficient, highlighting remarkable analogies with oscillating cylinders

The artist speaks: the interview as documentation

Nearly every exhibition catalogue now contains an interview with, or related statement by, the artist. How and why did this become the norm? The increasing popularity of the artist's words is traced back in this article to its roots in Romanticism, the rise of the mass media and the cult of the avant-garde artist. The value and reliability of the transcribed and printed words is questioned and a bibliography of published interviews with artists follows

The Scientist-Practitioner in a Counselling Psychology Setting

The human psyche is influenced by an extraordinary complexity of experiences. Many would therefore maintain that we can never completely understand another human being. As scientist-practitioners, is our purported allegiance to, and reliance upon, ‘official’ sources of knowledge (including theory and scientific evidence) sufficient for us to be confident that we can construct consistently helpful solutions from the myriad clinical data at our fingertips? Should we as psychologists accept that full understanding of causality is simply not an achievable objective? If we adopt the position that we can never fully explain causes, however, what role do we actually play? Can our interventions even be considered valid, let alone scientific? The question of how practitioners reflect upon their activity, and of the scientific assumptions behind their work, has occupied much debate in the field of psychology, and the many different strands of this debate are woven throughout the fabric of this book. In this chapter, we consider some of the many implications of this debate for counselling psychologists. Specifically, we begin by exploring the position of counselling psychology within the profession more broadly, and consider its place in the current controversy about the scientist-practitioner role. Next, we articulate some of our own practice in this regard, attempting not only to make note of the systematic approaches that we employ in counselling psychology but also to incorporate the wide range of expectation and experience that comes to the therapeutic endeavour. Finally, we try to define the type of scientist-practitioner that we envision in a counselling psychology setting

Predicting trend reversals using market instantaneous state

Collective behaviours taking place in financial markets reveal strongly correlated states especially during a crisis period. A natural hypothesis is that trend reversals are also driven by mutual influences between the different stock exchanges. Using a maximum entropy approach, we find coordinated behaviour during trend reversals dominated by the pairwise component. In particular, these events are predicted with high significant accuracy by the ensemble's instantaneous state.Comment: 18 pages, 15 figure

Clemmys

Number of Pages: 2Integrative BiologyEarth and Planetary Science