| Before COVID-19 | During COVID-19 | |
| Difference | -1747000 | -2025000 |
| Ratio | 0.8347 | 0.7746 |
Consider the optimal allocation between money market account and corporate bond fund. While the money market account is free of credit risk, corporate bonds are defaultable and exhibit long-range dependence (LRD) in credit risk. We propose a Volterra default intensity model to capture the LRD in credit risk. Using utility maximization, we derive the novel optimal investment strategy for a corporate bond fund. As empirical study shows that the COVID-19 pandemic has lowered the level of LRD in credit risk, we conduct sensitivity analysis and empirically investigate the changes in demand for corporate bonds before and during the pandemic period.
| Citation: |
Table 1. Comparison of the demand between before COVID-19 and during COVID-19 for Deutsche Bank corporate bond by indicators. Difference denotes disparity of trading volume on rising and declining days, and ratio is the relative value
| Before COVID-19 | During COVID-19 | |
| Difference | -1747000 | -2025000 |
| Ratio | 0.8347 | 0.7746 |
Table 2.
Calibrated parameters for the default intensity
| $ \delta=0.4 $ | $ \delta=0.5 $ | ||||
| Parameters | Before COVID-19 | During COVID-19 | Before COVID-19 | During COVID-19 | |
| $ \hat{\kappa} $ | 0.1565 | 0.0405 | 0.1714 | 0.2383 | |
| $ \hat{\sigma} $ | 0.5945 | 0.6179 | 0.5060 | 0.7089 | |
| $ \hat{\theta} $ | 0.2652 | 0.6673 | 0.3463 | 0.4717 | |
| $ \hat{H} $ | 0.5970 | 0.4888 | 0.5994 | 0.4070 | |
| $ \delta=0.7 $ | $ \delta=0.8 $ | ||||
| Parameters | Before COVID-19 | During COVID-19 | Before COVID-19 | During COVID-19 | |
| $ \hat{\kappa} $ | 0.1627 | 0.1713 | 0.1334 | 0.0356 | |
| $ \hat{\sigma} $ | 0.3328 | 0.4098 | 0.3087 | 0.3253 | |
| $ \hat{\theta} $ | 0.2269 | 0.2677 | 0.4380 | 0.7664 | |
| $ \hat{H} $ | 0.6471 | 0.4803 | 0.6324 | 0.4766 | |
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Deutsche Bank corporate bond (zero coupon, maturity: 04/22/26) before COVID-19
Deutsche Bank corporate bond (zero coupon, maturity: 04/22/26) under COVID-19