Bubble contagion effect between the main precious metals

Purpose: This study examines the extent to which gold and silver bubbles are correlated and which metal's bubble spills over to the other. In addition, the overlap in bubble-like episodes for the two metals is demonstrated and the influence of crises (global financial crises, European debt crisis and the COVID-19 pandemic) on the development of these episodes is compared. Design/methodology/approach: This study proposes a two-step approach. In the first step, price bubbles are identified based on the backward sup augmented Dickey–Fuller of Phillips et al. (2015a, 2015b) and modified by Phillips and Shi (2018). In the second step, the correlation in the contagion effect of the bubbles between the two precious metal prices is measured using a nonparametric regression with a time-varying coefficient approach developed by Greenaway-McGrevy and Phillips (2016). Findings: The findings suggest that the safe-haven property of gold and silver during financial market turbulence induces excessive price increases beyond their fundamental values. Furthermore, the results indicate that bubbles are contagious among precious metal markets and flow mainly from gold to silver;these findings are associated with the period after 2005, particularly during the global financial crisis. A contagious bubble effect is not found between gold and silver during the coronavirus disease 2020 pandemic. Practical implications: The results suggest that financial market participants should consider portfolio weights in precious markets in light of the bubble correlation between gold and silver, especially during crises. Originality/value: To the best of the authors' knowledge, this is the first study that explores the correlation of bubble-like episodes between gold and silver. © 2022, Emerald Publishing Limited.

COVID-19 vaccine humoral response and treatment effect in patients with hematologic malignancy

Background: Patients with hematologic malignancies have a lower vaccine response and higher rates for SARS CoV-2 morbidity and mortality. We present preliminary data focusing on humoral vaccine responses and correlates with disease subtype and treatment exposure. Methods: We analyzed data from 332 patients with a hematologic malignancy from May 1, 2021 - Jan 31, 2022 who received SARSCoV-2 vaccination and performed a prospective cohort serologic study with the Elecsys®Anti-SARSCoV-2-S test. Patients received homologous or heterologous vaccine combination of BNT162b2, mRNA1273, ChAdOx1 nCoV-19, and/or Ad26.COV2.S. Blood samples were obtained before any vaccination, 2-6 weeks after the second vaccine (2V), before third vaccine (3V), and 2-6 weeks after 3V. Results: The median age was 67 years (range 18-91years) with 41.9% female. At 2V, 11.5% and at 3V, 23.8% received heterologous vaccines. Treatment status at first vaccine dose significantly affected peak 2V antibody response (p < 0.05). Seropositive rate and median antibody titer after 2V for previously untreated patients were higher compared to patients on active therapy or had previously been treated. Treatment naïve (n = 60;seropositivity 85.1%;median titer 1306 U/mL;[Q1-Q3:11.4-> 2499]);first-line (1L) active therapy (n = 127;65.4%;41.25 U/mL;[ < 0.8-592.5]);second-line and beyond (2L+) active therapy (n = 56;60.7%;2.6U/mL;[ < 0.8-154]);previous treatment with 1L (n = 66;64.8%;118 U/mL;[ < 0.8-> 2499]);previous treatment with 2L+ (n = 23;59.1%;4U/mL;[ < 0.8-229.5]). Of 61 patients that were seronegative at 2V, 17 (27.9%) seroconverted after 3V. Anti-CD20 monoclonal antibody (mAb) containing therapy as the most recent treatment from 2V had the greatest impact on humoral response. Exposure to anti-CD20 mAb based regimens or as monotherapy revealed low antibody responses (n = 84;seropositivity 22.6%;median titer < 0.8 U/mL;Q1-Q3 [ < 0.8-< 0.8]). On analysis of indolent B-cell Non-Hodgkin Lymphomas whereby antiCD-20 mAb are often incorporated, treatment proximity to 2V impacted responses: < 3 months (n = 33;22%;< 0.8 U/ mL;[ < 0.8-< 0.8]) vs. 12-24 months (n = 4;60%;228 U/mL;[ < 0.8-232]). In contrast, tyrosine kinase inhibitor (n = 38;100%;858 U/mL;[221-> 2499]), proteosome inhibitor monotherapy (n = 4;100%;median titer 1520 U/mL;[462-> 2499]) were among the subgroups with the highest numerical responses, however, the addition of corticosteroids impacted vaccine response as seen in proteosome inhibitor with corticosteroids (n = 7;85.7%;6.6 U/mL;[1.8-115.2]). Conclusions: The humoral response from our single institution cohort identifies diminished responses depending on treatment status and the type of treatment including the proximity of treatment exposure to receipt of vaccination. Furthermore, vaccine boosters can induce antibody responses in patients who were previously seronegative.

Bubble contagion effect between the main precious metals

Purpose: This study examines the extent to which gold and silver bubbles are correlated and which metal’s bubble spills over to the other. In addition, the overlap in bubble-like episodes for the two metals is demonstrated and the influence of crises (global financial crises, European debt crisis and the COVID-19 pandemic) on the development of these episodes is compared. Design/methodology/approach: This study proposes a two-step approach. In the first step, price bubbles are identified based on the backward sup augmented Dickey–Fuller of Phillips et al. (2015a, 2015b) and modified by Phillips and Shi (2018). In the second step, the correlation in the contagion effect of the bubbles between the two precious metal prices is measured using a nonparametric regression with a time-varying coefficient approach developed by Greenaway-McGrevy and Phillips (2016). Findings: The findings suggest that the safe-haven property of gold and silver during financial market turbulence induces excessive price increases beyond their fundamental values. Furthermore, the results indicate that bubbles are contagious among precious metal markets and flow mainly from gold to silver;these findings are associated with the period after 2005, particularly during the global financial crisis. A contagious bubble effect is not found between gold and silver during the coronavirus disease 2020 pandemic. Practical implications: The results suggest that financial market participants should consider portfolio weights in precious markets in light of the bubble correlation between gold and silver, especially during crises. Originality/value: To the best of the authors’ knowledge, this is the first study that explores the correlation of bubble-like episodes between gold and silver. © 2022, Emerald Publishing Limited.

Have returns and volatilities for financial assets responded to implied volatility during the COVID-19 pandemic?

This paper uses transfer entropy measures to analyze the information sharing between the option implied volatility, the realized volatility and the returns of six financial assets during the COVID-19 pandemic. The measures indicate increases in the information transmissions during the pandemic which are uniform across the volatilities and the returns of all assets. In these transmissions, the option implied volatilities are found to play the central role, particularly in the returns of the assets as opposed to its realized volatilities. Thus, we may conclude that the predictability of the volatilities derived from option pricing models has improved during the pandemic and that this improvement has reduced the uncertainty of the future returns and the volatilities, albeit to a lower extent. These findings bear implications for constructing models that predict volatilities and returns during crises periods. © 2021 Elsevier B.V.