[During the recent financial crisis, ABX.HE index credit default swaps (CDS) on baskets of mortgage-backed securities were a benchmark widely used by financial institutions to mark their subprime mortgage portfolios to market. However, we find that prices for the AAA ABX.HE index CDS during the crisis were inconsistent with any reasonable assumption for mortgage default rates, and that these price changes are only weakly correlated with observed changes in the credit performance of the underlying loans in the index, casting serious doubt on the suitability of these CDS as valuation benchmarks. We also find that the AAA ABX. HE index CDS price changes are related to short-sale activity for publicly traded investment banks with significant mortgage market exposure. This suggests that capital constraints, limiting the supply of mortgage-bond insurance, may be playing a role here similar to that identified by Froot (2001) in the market for catastrophe insurance.]

This paper models and provides empirical evidence for the quality of assets that are securitized through bankruptcy remote special purpose vehicles (SPVs). The model predicts that assets sold to SPVs will be of lower quality (“lemons”) compared to assets that are not sold to SPVs. We find strong empirical support for this prediction using a comprehensive data set of sales of mortgage-backed securities (Freddie Mac Participation Certificates, or PCs) to SPVs over the period 1991 through 2002. Valuation estimates based on a structural two-factor model indicate that PCs sold to SPVs are on average valued $0.39 lower per $100 of face value relative to PCs not so sold. For the four largest coupon groups in our full sample of Freddie Mac PCs, we find a “lemons spread” of 4–6 basis points in terms of yield-to-maturity, and this spread accounts for 13–45% of the overall prepayment spread of these securities.

[This paper models and provides empirical evidence for the quality of assets that are securitized through bankruptcy remote special purpose vehicles (SPVs). The model predicts that assets sold to SPVs will be of lower quality ("lemons") compared to assets that are not sold to SPVs. We find strong empirical support for this prediction using a comprehensive data set of sales of mortgage-backed securities (Freddie Mac Participation Certificates, or PCs) to SPVs over the period 1991 through 2002. Valuation estimates based on a structural two-factor model indicate that PCs sold to SPVs are on average valued $0.39 lower per $100 of face value relative to PCs not so sold. For the four largest coupon groups in our full sample of Freddie Mac PCs, we find a "lemons spread" of 4-6 basis points in terms of yield-to-maturity, and this spread accounts for 13-45% of the overall prepayment spread of these securities.]

Two important issues in econometric freight transportation demand analysis are addressed: (1) the simultaneity between quantity shipped and mode/destination choices, and (2) the effect of spatial price competition on the demand for the transportation factor. In the theoretical model, spatial price competition determines the firm's market area and, thus, determines its sales and shipment sizes. The model is estimated using switching regression techniques, since shipment size and mode/destination choice are derived from the same optimization problem. The empirical model provides consistent estimates of unconditional freight demand. These estimates are needed to forecast transportation flows and derive elasticities for policy analysis. Copyright 1989 by MIT Press.

During the recent financial crisis, ABX.HE index credit default swaps (CDS) on baskets of mortgage-backed securities were a benchmark widely used by financial institutions to mark their subprime mortgage portfolios to market. However, we find that prices for the AAA ABX.HE index CDS during the crisis were inconsistent with any reasonable assumption for mortgage default rates, and that these price changes are only weakly correlated with observed changes in the credit performance of the underlying loans in the index, casting serious doubt on the suitability of these CDS as valuation benchmarks. We also find that the AAA ABX.HE index CDS price changes are related to short-sale activity for publicly traded investment banks with significant mortgage market exposure. This suggests that capital constraints, limiting the supply of mortgage-bond insurance, may be playing a role here similar to that identified by Froot (2001) in the market for catastrophe insurance. The Author 2011. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: [email protected]., Oxford University Press.

We develop a theoretical model of a network of intermediaries whose optimal behavior is jointly determined, leading to heterogeneous financial norms and systemic vulnerabilities. We apply the model to the network of U.S. mortgage intermediaries from 2005 to 2007, using a data set containing all private-label, fixed-rate mortgages, with loan flows defining links. Default risk was closely related to network position, evolving predictably among linked nodes, and loan quality estimated from the model was related to independent quality measures, altogether pointing to the vital importance of network effects in this market. Received April 20, 2016; editorial decision July 11, 2017 by Editor Stijn Van Nieuwerburgh.

This paper conducts a comprehensive study of the optimal exercise policy for an executive stock option and its implications for option cost, average life, and alternative valuation concepts. The paper is the first to provide analytical results for an executive with general concave utility. Wealthier or less risk-averse executives exercise later and create greater option cost. However, option cost can decline with volatility. We show when there exists a single exercise boundary, yet demonstrate the possibility of a split continuation region. We also show that, for constant relative risk averse utility, the option value does not converge to the Black and Scholes value as the correlation between the stock and the market portfolio converges to one. We compare our model's option cost with the modified Black and Scholes approximation typically used in practice and show that the approximation error can be large or small, positive or negative, depending on firm characteristics.

ABSTRACT We develop an empirical model of employee stock option exercise that is suitable for valuation and allows for behavioral channels. We estimate exercise rates as functions of option, stock, and employee characteristics using all employee exercises at 88 public firms, 27 of them in the S&P 500. Increasing vesting frequency from annual to monthly reduces option value by 11% to 16%. Men exercise faster, reducing value by 2% to 4%, while top employees exercise slower, increasing value by 2% to 7%. Finally, we develop an analytic valuation approximation that is more accurate than methods used in practice.

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