**Preface to "Financial Statistics and Data Analytics"**

This book brings state-of-art knowledge in the field of financial statistics and data analytics to the fore.

The paper by Carolina Prihandinisari et al. reviews research and theory on the important topic of labor turnover resulting from issues related to job performance and/or job satisfaction which have, in turn, been initiated by changes in work motivation.

Bahadır Yuzba and Ejaz Ahmed's paper suggests improved estimation strategies based on ¨ preliminarily test and shrinkage principles in a seemingly unrelated regression model when explanatory variables are affected by multicollinearity.

The paper by Manuel Galea et al. considers asset pricing models under the multivariate t-distribution with finite second moment. Chuxuan Jiang et al. test for multifractal scaling across several financial time series including Bitcoin and find that multifractal scaling cannot be ruled out for Bitcoin or the Nasdaq Composite Index, both technology-driven assets.

Eduardo Mineo et al. propose DCOBS with no-arbitrage restrictions, a dynamic constrained smoothing B-splines yield curve model. Maria Karadima and Helen Louri examine the evolution of competition (through market power and concentration) and credit risk (through non-performing loans) in 2005–2017 across all euro area countries (EA-19), as well as core (EA-Co) and periphery (EA-Pe) countries separately. In their second paper, they provide detailed answers to the remarks made by Tsionas on the use of stochastic frontier-based measures of market power in part of an empirical study, which examines the fragmentation and convergence dynamics of market power, concentration, and credit risk in the euro area banking sector during 2005–2017.

Danubia R. Cunha et al. examine a general family of Birnbaum–Saunders autoregressive ´ conditional duration (BS-ACD) models based on generalized Birnbaum–Saunders (GBS) distributions, denoted by GBS-ACD. Tronzano focuses on three "safe haven" assets (gold, oil, and the Swiss Franc) and examines the impact of recent financial crises and some macroeconomic variables on their return co-movements during the last two decades.

Juan Carlos Ruilova and Pedro Alberto Morettin study a variant of the GARCH model when we consider the arrival of heterogeneous information in high-frequency data. Ashis SenGupta and Moumita Roy obtain a simple and efficient estimator of the index parameter of symmetric stable distribution that holds universally, i.e., over the entire range of the parameter. They appeal to directional statistics on the classical result on the wrapping of a distribution in obtaining the wrapped stable family of distributions.

This book will be useful for graduate students and researchers working in any area related to financial statistics and data analytics.

Finally, we would like to thank all the authors and reviewers for their contributions, and our colleagues at the Editorial Office for their support and assistance.

> **Shuangzhe Liu, Milind Sathye** *Editors*
