Empirical Economics最新文献

Abstract

In this paper, we consider a fractionally integrated multi-level dynamic factor model (FI-ML-DFM) to represent commonalities in the hourly evolution of realized volatilities of several international exchange rates. The FI-ML-DFM assumes common global factors active during the 24 h of the day, accompanied by intermittent factors, which are active at mutually exclusive times. We propose determining the number of global factors using a distance among the intermittent loadings. We show that although the bulk of common dynamics of exchange rates realized volatilities can be attributed to global factors, there are non-negligible effects of intermittent factors. The effect of the COVID-19 on the realized volatility comovements is stronger on the first global-in-time factor, which shows a permanent increase in the level. The effects on the second global factor and on the intermittent factors active when the EU, UK and US markets are operating are transitory lasting for approximately a year after the pandemic starts. Finally, there seems to be no effect of the pandemic neither on the third global factor nor on the intermittent factor active when the markets in Asia are operating.

This paper proposes a nonlinear fractional unit root approach which is known as the autoregressive neural network–fractional integration (ARNN–FI) test. This new fractional integration test is based on a new multilayer perceptron of a neural network process, proposed in Yaya et al. (Oxf Bull Econ Stat 83(4):960–981, 2021). The asymptotic theory and the properties of the proposed test are given. By setting up a Monte Carlo simulation experiment, the simulation results reveal that as the number of observations increases, size and power distortions would disappear in the test. The empirical application based on this new test reveals that the unemployment rates of three European countries are neither stationary nor mean-reverting in line with the hysteresis hypothesis.

Study objectives: In coronary artery bypass grafting (CABG), abnormal cardiac repolarization is associated with adverse cardiovascular events that can be measured via the QTc interval. We investigated the impact of obstructive sleep apnea on the change in repolarization after CABG and the association of change in repolarization with the occurrence of major adverse cardiac and cerebrovascular events.

Methods: A total of 1,007 patients from 4 hospitals underwent an overnight sleep study prior to a nonemergent CABG. Electrocardiograms of 954 patients (median age: 62 years; male: 86%; mean follow-up: 2.1 years) were acquired prospectively within 48 hours before CABG (T1) and within 24 hours after CABG (T2). QTc intervals were measured using the BRAVO algorithm by Analyzing Medical Parameters for Solutions LLC. The change in T2 from T1 for QTc (ΔQTc) was derived, and Cox regression was performed.

Results: Compared with those without, patients who developed major adverse cardiac and cerebrovascular events (n = 115) were older and had (1) a higher prevalence of smoking, hypertension, diabetes mellitus, and chronic kidney disease; (2) a higher apnea-hypopnea index and oxygen desaturation index; and (3) a smaller ΔQTc. Cox regression analysis demonstrated a smaller ΔQTc to be an independent risk factor for major adverse cardiac and cerebrovascular events (hazard ratio: 0.997; P = .032). In the multivariable regression model, a higher oxygen desaturation index was independently associated with a smaller ΔQTc (correlation coefficient: -0.58; P < .001).

Conclusions: A higher preoperative oxygen desaturation index was an independent predictor of a smaller ΔQTc. ΔQTc within 24 hours after CABG could be a novel predictor of occurrence of major adverse cardiac and cerebrovascular events at medium-term follow-up.

Clinical trial registration: Registry: ClinicalTrials.gov; Name: Undiagnosed Sleep Apnea and Bypass OperaTion (SABOT); URL: https://classic.clinicaltrials.gov/ct2/show/NCT02701504; Identifier: NCT02701504.

Citation: Teo YH, Yong CL, Ou YH, et al. Obstructive sleep apnea and temporal changes in cardiac repolarization in patients undergoing coronary artery bypass grafting. J Clin Sleep Med. 2024;20(1):49-55.

Abstract

We analyze diverse and heterogeneous literature to grasp the general effect size of financial development on economic growth on a world scale. For that, we perform by far the largest available meta-analysis of the finance–growth nexus using 3561 estimates collected from 177 studies. Our meta-synthesis results show that large heterogeneity in empirical evidence is, in fact, driven by only a limited number of variables (moderators). By using advanced techniques, we also document the existence of the publication selection bias that is propagated in the literature in a nonlinear fashion. We account for uncertainty in moderator selection by employing model-averaging techniques. After adjusting for the publication bias, the results of our meta-regression provide evidence of a small but genuine positive effect of the financial development on growth that very mildly declines over time. Finance channeled via capital markets seems to be more beneficial for economic growth than that provided in the form of private credit. Our evidence goes against arguments about the damaging role of financial development and is in line with century-old theoretical foundations that favor the positive role of finance on economic growth.

We explore how the type of global market entry affects wage premia, classifying firms into four categories: domestic only, domestic exporters, non-exporting multinationals, and exporting multinational enterprises. Using firm-level panel data for Bosnia and Herzegovina, Croatia, and Slovenia for the years 2007–2017 and a multivariate endogenous treatment model based on the approach of Wooldridge (J Econom 68(1):115–132, 1995), we find that the multinational wage premia are mainly driven by the export status of multinational firms. Specifically, domestic exporters and exporting multinationals pay on average higher wages than non-exporting firms, whereas non-exporting multinationals tend to pay lower wages than domestic-only firms.

Abstract

The estimated effect of childcare availability on maternal labor supply varies highly in previous single-country estimates. We provide comparable quasi-experimental estimates of the childcare effect for seven countries, using harmonized data and a uniform method based on country-specific childcare eligibility cutoffs. We evaluate the estimates in light of key institutional factors to determine under what conditions childcare expansion is likely to be effective. We propose a measure that captures childcare scarcity and predicts the effectiveness of childcare expansion: the gap between the participation rate of mothers with older children (aged 6–14) and childcare coverage under the age of 3. In countries with a high gap, we find that childcare availability has a significant positive impact on maternal labor supply (Austria, Czech Republic, Hungary, Slovak Republic). No significant impact is found in countries where the gap is low due to either already high childcare coverage (France) or the low participation of mothers with older children (Greece, Italy). We discuss other policies that need to be addressed concurrently for childcare expansion to achieve its goal of increasing mothers’ participation in the labor market.

This study explores house price fluctuations in the USA and shed light on which factor is the main contributor driving house prices. In order to decompose the changes in house prices, structural vector autoregression with sign restrictions for the US housing market is applied. In addition to including housing market-based fundamental variables such as the number of housing permits, housing rent prices, house prices, a measure of credit conditions, and the housing sentiment index are also included to distinguish four different shocks, namely housing supply shocks, shocks to the housing service demand, credit shocks, and speculative demand shocks. Empirical findings show that the main contributors to house price fluctuations are credit shocks and housing supply shocks in the long-run. In addition, while housing supply and credit conditions are the most important contributors during the boom, the contributions of credit conditions and speculative demand become larger after the boom. In fact, credit conditions are the largest contributor during the post-boom period.