We study the ambiguity-adjusted return distribution induced by an investor with smooth ambiguity preferences 'a la Klibano! et al. (2005), who faces uncertainty about the variance of asset returns. The variance uncertainty is modeled using a gamma distribution, a second-order prior over the...

The stability of global energy markets is fundamental to effective energy strategy, influencing national policy and corporate investment decisions. Extreme volatility, such as during the COVID-19 pandemic, exposes the limitations of conventional risk assessment tools and undermines strategic...

This research explores the application of extreme value theory in modelling and quantifying tail risks across different economic equity markets, with focus on the Nairobi Securities Exchange (NSE20), the South African Equity Market (FTSE/JSE Top40) and the US Equity Index (S&P500). The study...

We propose a robust semi-parametric framework for persistent time-varying extreme tail behavior, including extreme Value-at-Risk (VaR) and Expected Shortfall (ES). The framework builds on Extreme Value Theory and uses a conditional version of the Generalized Pareto Distribution (GPD) for...

We investigate the impact of structural shocks on the joint distribution of future real GDP growth and inflation in the euro area. We model the conditional mean of these variables, along with selected financial indicators, using a VAR and perform quantile regressions on the VAR residuals to...

Effective monetary policy requires maintaining the short-term interbank rate close to the policy rate while limiting its volatility, ensuring smooth transmission, and reducing banks' liquidity and interest rate risks. This paper seeks to identify and explain the drivers of volatility in...

This paper investigates persistence in the MINT (Mexico, Indonesia, Nigeria, Turkey) stock markets applying fractional integration methods to daily data from 1 January 2022 to 31 October 2025. Different model specifications are estimated for prices, log prices and log returns under the...

Statistical inference-both estimation and testing-for stochastic volatility (SV) models is known to be challenging and computationally demanding. We propose simple and efficient estimators for SV models with conditionally heavy-tailed error distributions, particularly the Student's t and...

We derive an admissible parameter space for vector Multiplicative Error Models (vMEMs), explicitly formulating it in terms of the model's matrix parameters through a set of matrix inequalities. Another key contribution is the adoption of constrained maximum likelihood estimation for the...

This paper evaluates an Adaptive LASSO-MGARCH model for multivariate volatility forecasting, with an application to green and conventional bonds, equities, energy commodities, and EU carbon allowances. By introducing coefficient-specific adaptive penalisation directly into the multivariate GARCH...

We uncover momentum and reversal patterns in half-day option returns that persist for up to at least 20 business days, with economic magnitudes of 0.22% to 0.45% per half-day. Specifically, returns show strong momentum within the same period (e.g., intraday-to-intraday) but reverse sharply...

Der Green Startup Report 2026, herausgegeben vom Borderstep Institut für Innovation und Nachhaltigkeit, analysiert die aktuelle Entwicklung der grünen Gründungslandschaft in Deutschland und setzt die seit 2013 kontinuierlich durchgeführte wissenschaftliche Beobachtung der Szene fort. Die...

Recent studies have focused on the detrimental effects of global economic policy uncertainty (EPU) on firm profitability. Nevertheless, none of these studies has focused on a developing economy like Nigeria. To understand this, the study conducted a host of regression analyses using the Driscoll...

This paper investigates how external shocks propagate through fiscal transmission mechanisms in a commodity-dependent economy within a dynamic macroeconomic framework. The study contributes to the literature on macroeconomic fluctuations by examining the interaction between external revenue...

This study explores how the volatility spillover mechanism and dynamic dependence among the founding BRICS equity markets, namely IBOVESPA, MICEX, Nifty 50, SSE, and JSE, have evolved over time using a multivariate DCC-GARCH model. The analysis is conducted across three distinct regimes: the...

Inequality of wealth or liquid finance in a system with credit market imperfection adversely affects investment by poor investors. This is well known in the literature. In this paper we prove that the aggregate credit demand function would be relatively inelastic with unequal wealth distribution...

This study investigates the long-memory properties of the prices of three Kenyan commodities (tea, coffee and horticultural products) by applying fractional integration methods to monthly data spanning the period from August 1998 to December 2024. The empirical results provide evidence of...

This study investigates the volatility spillover dynamics between the VIX fear index and the Magnificent Seven technology stocks - namely Microsoft, Apple, Nvidia, Amazon, Alphabet, Meta Platforms, and Tesla - over the period of June 2012 to March 2024. To achieve this objective, the variance...

Hirschman's Exit, Voice, and Loyalty (1970) proposed that organizations persist when loyalty tempers incentives to exit after adverse shocks. We test this argument using newly digitized individual-level voting records from 28 English constituencies (1832-1868), covering 134,000 real votes....

The worldwide move toward renewable energy indicates a fundamental change that is particularly important in the MENA region, which has abundant renewable resources and has depended on hydrocarbon economies. This study presents an empirical examination of key macroeconomic determinants-inflation,...

This paper examines the asymmetric impact of economic policy uncertainty (EPU) on exchange rate volatility across a sample of developed and emerging economies. Using an asymmetric GARCH-MIDAS model, volatility is decomposed into short-term and long-term components, with the latter associated...

This study applies a multiple threshold nonlinear autoregressive distributed lag (MTNARDL) model to examine the asymmetric impact of real exchange rate volatility on Vietnam's exports and imports with its three leading trading partners: China, the United States, and South Korea. By allowing...

We argue that negative skew and positive mean of the distribution of stock returns are largely due to the broken symmetry of stochastic volatility governing gains and losses. Starting with stochastic differential equations for stock returns and for stochastic volatility, we argue that the...

This study examines the role of volatility mean reversion in option pricing and evaluates the performance of commonly used volatility estimators within a broad market context. Using a comprehensive dataset of end-of-day option chains for the 100 most actively traded U.S. equities from 2018 to...