Life Insurance Settlement and the Monopolistic Insurance Market Jimin Hong Business School Seoul National University 1 Gwanak Ro, Gwanak Gu, Seoul, 151-916, Korea [email protected] S. Hun Seog1 Business School Seoul National University 1 Gwanak Ro, Gwanak Gu, Seoul, 151-916, Korea [email protected] 1 Seog is grateful for the financial support from the Management Research Institute of the Seoul National University. Life Insurance Settlement and the Monopolistic Insurance Market 2014.6. Abstract: We analyze the effects of life insurance settlement on the insurer’s profit and the consumer and social welfare. We consider a one-period model in which the insurance market is monopolistic and the settlement market is competitive. Policyholders face heterogeneous liquidity risks in addition to mortality risks. Liquidity risks are introduced to address the case in which policyholders need urgent cash, leading them to surrender or settle the policies. It is assumed that the insurer cannot observe the liquidity risks nor discriminate among policyholders based on liquidity risk. It is further assumed that no costs are incurred in policy surrender or settlement. We find that introduction of the life settlement market lowers monopolistic rent and insurer’s profit, and raises the insurance premium. The effects on consumer welfare and social welfare are mixed. Consumer welfare increases only when demand increases sufficiently. This finding implies that social welfare, as measured by the sum of consumer welfare and the insurer's profit, can increase if the increase in consumer welfare is greater than the decrease in insurer's profit. This finding contrasts with the existing literature, in which the settlement market lowers consumer and social welfare. Keywords: life insurance, settlement market, consumer welfare, monopoly, social welfare Life Insurance Settlement and the Monopolistic Insurance Market I. Introduction Life settlement is a transaction such that a policyholder sells her insurance policy to a third party investor, a so-called settlement provider. As a result of the transaction, the policyholder receives the settlement price, while the investor becomes the beneficiary of the life insurance. Life settlement has been used by policyholders as a means of securing cash. Without the settlement market, the policyholder can surrender the policy to receive cash, called the surrender value. Therefore, the life settlement market provides the policyholder with an alternative to policy surrender. Given that surrender value is generally lower than the actuarial value of the insurance contract, a policyholder may opt to settle the policy rather than surrendering it when the settlement price is higher than the surrender value. Life settlement also benefits financial investors in several ways. First, since the settlement price is lower than the actuarial value, investors may earn profits. Profits can be greater when policyholders settle policies when there is an urgent need for cash. Second, policy settlement can provide investors with investment opportunities that are not correlated with existing portfolios. The inclusion of life settlement in investment portfolios will lower portfolio risks. According to Gatzert (2010), settlement transactions are allowed in Germany, the U.K. and the U.S. For example, terminally-ill AIDS patients are allowed to sell their policies in the settlement market in the U.S. Conning Research & Consulting (2008) reported that the size of the U.S. settlement market was 120 billion dollars in 2007 and that it may reach one trillion dollars in 2016. Several economic studies address life settlement. Doherty and Singer (2002) argue that the settlement market may enhance consumer welfare, since it can reduce the monopsony power of the insurer. They observe that, without the settlement market, the policyholder would surrender the policy to the insurer, where the insurer plays a role similar to a monopsonistic firm. The introduction of a settlement market effectively increases competition among buyers, which lowers the monopsony rent of the insurer. Based on Hendel and Lizzeri (2003), Daily, Hendel and Lizzeri (2008, DHL hereafter), consider a dynamic insurance contract in a competitive insurance market. The insurance contract is a one-sided commitment which means only the insurer’s commitment is binding. They assume that the policyholder’s income is growing and that the insurer can observe the policyholder’s health risk (symmetric learning). DHL focused on the zero cash surrender value (CSV) and the “front-loaded” contracts, in which policyholders pay front-loaded premiums. Front loading allows the policyholder to avoid reclassification risk in the following period. When a policyholder surrenders her policy, the insurer can get the surrender profit from the prepaid front loaded premium. DHL argues that the introduction of a settlement market lowers consumer welfare, because the premium increases and the policyholder is unable to hedge the reclassification risk. They, however, conjecture that the settlement market may improve consumer welfare if the income stream is reversed. Fang and Kung (2008, FK hereafter) extend the discrete model of DHL into the continuous model. Unlike DHL, FK allow a non-zero CSV whose value is dependent on the policyholder’s health condition. FK's findings are in line with DHL. FK shows that the optimal CSV is equal to zero and that the settlement deteriorates consumer welfare because consumers lose the hedging opportunity as well. On the other hand, Hong and Seog (2012) analyze the case in which the income stream is reverse in the DHL model. They refute the conjecture of DHL. That is, even if the income stream decreases from high to low, the introduction of a settlement market still lowers consumer welfare because policyholders lose the opportunity to hedge the reclassification risk. Seog and Hong (2012) investigate the effects of a settlement market on the monopolistic insurance market, where death benefits as well as the CSV and premiums are determined endogenously. These authors find that the monopolistic insurer can fully extract the consumer surplus through adjustment of premiums, and the policyholder can fully hedge the risk. Unlike DHL and FK, the CSV can be positive. The CSV is less than or equal to the actuarial value of insurance. When a settlement market is introduced, social welfare tends to decrease, as the monopoly rent of the insurer decreases, while consumer welfare remains zero. Gatzert, Hoermann and Schmeiser (2008) argue that the introduction of a settlement market may worsen the insurer’s profit using a simulation based on actuarial assumptions. The profit is reduced because the insurer needs to pay a higher benefit instead of a lower surrender value. The profit reduction also leads to a rise in premiums. Along a similar line of thinking, this paper investigates the effects of the settlement market on the design of insurance contracts, consumer welfare and social welfare. We consider a monopolistic insurer and a competitive settlement market. The focus of this paper is on the liquidity risk of policyholders, which reflects the fact that the settlement market has been often used by policyholders who need cash for medical treatment or urgent care. Facing liquidity needs, policyholders should decide whether to surrender or settle the policy. We assume that policyholders face heterogeneous liquidity risks and that the insurer cannot observe the liquidity risks. We further assume that the insurer cannot offer contracts that discriminate against policyholders based on the liquidity risks. This assumption reflects the observation that insurers are often disallowed from discriminating against policyholders based on non-insurance risks. Policyholders are homogeneous except for their liquidity risks. We find that the introduction of the settlement market lowers monopolistic rent of the insurer, while increasing insurance premiums. As a result, the insurer's profit decreases. The effects on welfare are mixed, depending on the distribution of liquidity risks and the utility shapes of policyholders. Consumer and social welfare can be improved when the changes in insurance contracts attract a sufficient number of potential policyholders. This finding contrasts with published studies that claim that the settlement market deteriorates welfare. The remainder of the paper is proceeds as follows. Section II provides the model description. Section III investigates the basic model with no settlement market. Section IV studies the model with a settlement market. Sections V and VI study the effects of the settlement market on the insurance contract, and on the consumer and social welfare, respectively. Sections VII and VIII deal with the example and compare it with the competitive insurance market. Section IX discusses the implications of the findings. Section X set forth the conclusions. II. Model description We consider a monopolistic insurance market in a one period model. Time is denoted by t = 0 and t = 1. A potential policyholder purchases life insurance in t = 0, and the death event occurs with probability p1 in t = 1. The insurance premium is denoted by Q and the death benefit of insurance is fixed as D. The premium is composed of pure premium and the monopolistic rent which is denoted by R. We assume that policyholders are homogeneous except for liquidity risk. Liquidity risk is measured by the probability that the policyholder needs urgent cash, which is denoted by q which is distributed on [0, 1]. It is assumed that the event of cash need occurs immediately prior to death event in t = 1. When the policyholder needs cash, the policyholder has to surrender the policy to the insurer and receive surrender value S, if there is no settlement market. However, the policyholder can choose between surrender and settlement, if a settlement market exists. The population of potential policyholders is distributed over the liquidity risk. The population density function (p.d.f.) and the cumulative density function (c.d.f.) of q are denoted by f(q) and F(q), respectively. The monopolistic insurer cannot observe the liquidity risk nor offer contracts that discriminate among policyholders based on their liquidity risk. The discount factor is denoted by ρ. The time line of the model is depicted in Figure 1. Suppose that there is no settlement market. When the insurer sells insurance to a policyholder with liquidity risk q, the pure premium becomes qS + (1 – q)p1D. With rent R, premium Q can be denoted as follows. Q qS (1 q) p1D R (1) Let us denote the endowment income of policyholders as W at t = 0. In t = 1, the policyholder experiences a liquidity crisis, so the income flow would be W - y with probability q or the income would be W1 with probability 1- q. We suppose that the policyholder considers two sources of utility. If the policyholder is alive and her consumption is W, then the utility is denoted as u(W ) . However, if the policyholder is dead and a dependent spends W, then the utility becomes v(W ) . This assumption is in accordance with DHL and FK. The policyholder incorporates the dependent’s consumption into her expected utility, reflecting a bequest motive. Utility functions are strictly concave and twice differentiable. That is, u '(W ) 0, u ''(W ) 0 and v '(W ) 0, v ''(W ) 0 . The policyholder’s expected utility with no insurance can be written as u(W ) qu(W y) (1 q)(1 p1 )u(W1 ) . The expected utility with insurance is as follows: u(W Q) qu(W y S ) (1 q) p1v(D) (1 p1 )(1 q)u(W1 ) The difference between the two expected utilities with and without insurance is called the net benefit of the policyholder, or NB(q). NB(q) can be expressed as follows. NB(q) u(W Q) qu(W y S ) (1 q) p1v(D) (1 p1 )(1 q)u(W1 ) [u(W ) qu(W y) (1 q)(1 p1 )u(W1 )] We suppose that u(W y S ) [ p1v( D) u(W y)] . That is, the utility to hold the insurance is higher than the utility to lapse the insurance. This assumption allows us to avoid the case that the insured chooses the surrender strategically to obtain the cash when surrender value is high. III. The basic model : no settlement market 1. Demand given target liquidity risk The monopolistic insurer determines the premium and the surrender value to maximize the (expected) profit. Since policyholders have different liquidity risks and the insurer cannot offer a contract conditional on liquidity risk, policyholders may have different preferences over the insurance contract terms. Only those who obtain nonnegative net benefits will purchase insurance. Let us refer to the marginal policyholder (liquidity risk) with zero net benefit as a target policyholder (liquidity risk). Technically, a target policyholder’s net benefit is as follows. NB(q) u(W Q) qu(W y S ) (1 q) p1v(D) (1 p1 )(1 q)u(W1 ) (2) [u(W ) qu(W y) (1 q)(1 p1 )u(W1 )] 0 Now, Lemma 1 is obtained. Lemma 1. Potential policyholders with lower liquidity risk than the target liquidity risk purchase insurance. Proof. See the Appendix.// In this case, potential policyholders with lower liquidity risk than the target obtain positive net benefits such that they prefer to purchase insurance. This result also implies that the insurer cannot fully extract rents from policyholder, allowing policyholders to enjoy positive net benefits. 2. Surrender value and target liquidity risk The insurer will determine optimal premium Q and optimal surrender value S for profit maximization. From (1) and (2), the problem is equivalent to finding optimal surrender value S* and target liquidity risk q* in ( R(S , q), S , q) . Note that rent R, and thus premium Q, follow from (2). The problem for target risk q’, R’,S’ and Q’ can be written as: Max ( R '( S ', q '), S ', q ') S ', q ', R Q ' F (q ') S ' qf (q)dq p1D (1 q) f (q)dq q' q' 0 0 [ S ' p1D][q ' F (q ') qf (q)dq] R ' F (q ') q' 0 s.t. u(W Q) q ' u(W y S ') (1 q ') p1v(D) (1 q ')(1 p1 )u(W1 ) [u(W ) q ' u(W y) (1 q ')(1 p1 )u(W1 )] 0 where Q ' q ' S (1 q ') p1D R ' (3) Note that monopolistic profit is composed of the difference between the surrender value and the fair value of the death benefit and rent. If the fair value is greater than the surrender value, the difference term is negative. That is, the insurer paid a higher benefit than the benefit for which it set the price. Now, we obtain Proposition 1 by solving (3). Proposition 1. The optimal surrender value S *, R * and q * satisfy (4) and (5). q' u '(W Q) qf (q)dq qF (q)u '(W y S ) (4) 0 Rf (q) [ p1v( D) u (W y) u (W y S )] u '(W Q ') F (q ) (5) where Q ' q ' S (1 q ') p1D R ' Proof. See the Appendix. // The LHS of (4) measures the sum of the policyholders’ net benefit decrease following the premium increase due to the increase in S. Since the insurer needs to compensate the target policyholder for the net benefit decrease, the LHS also indicates the marginal cost for the insurer. The RHS of (4) measures the sum of the net benefits increase following the surrender value increase. It indicates the marginal revenue of the insurer. As a result, (4) requires marginal revenue to equal marginal cost at the optimal surrender value. On the other hand, (5) indicates the condition that in optimum, revenue change is equal to cost change following the premium decrease due to the increase in q, and the increase in q itself. That is, the marginal revenue of the insurer is equivalent to the marginal cost to the insurer. We prove a detailed proof process in the Appendix. 3. Consumer welfare and social welfare Let us define consumer welfare (CW) as the sum of the net benefit of all consumers. Given S*, R*, and q*, CW can be expressed as: CW u (W Q*) F (q*) u (W y S *) qf (q)dq p1v( D) (1 q) f (q)dq q* q* 0 0 u(W ) F (q*) u(W y) qf (q)dq q* 0 (6) We transform (6) using (2): CW [q * F (q*) qf (q)dq][ p1v( D) u (W y ) u (W y S *)] q* 0 (7) From (7), we know that the consumer welfare comprises the difference in utility between holding the insurance and surrender the insurance. The insurer can extract the utility difference as qf (q)dq . However, policyholders enjoy the utility difference as q * F (q*) , q* 0 because the insurer cannot discriminate among policyholders depending on liquidity risk q . Similarly, let us define social welfare (SW) as the sum of the consumer welfare and the insurer’s profit. Thus,; SW CW [q * F (q*) qf (q)dq][ p1v( D) u (W y) u (W y S *) ( p1D S *)] q* R * F (q*) IV. 0 (8) The model with a settlement market 1. Demand given target liquidity risk Suppose that a competitive settlement market exists. We assume that the market is perfect, so there is no transaction cost and the investors (settlement providers) are risk neutral. As a result, a policyholder can sell her policy at an actuarially fair price, p1 D , in the settlement market. Our task is to seek the equilibrium outcome for the insurance contract when the settlement market exists. For notational clarity, we add script s to indicate the existence of the settlement market: for example, liquidity risk qs, surrender value Ss and so on. Applying the same logic as Lemma 1, we easily obtain the result that potential policyholders with lower liquidity risks than the target risk prefer to purchase insurance. 2. Surrender value First, note that if S* as determined in (5) is greater than or equal to p1 D , then the settlement market cannot exist because policyholders opt to surrender rather than settle. Therefore, if the settlement market is to be meaningful, S* should be lower than p1 D . The condition that settlement investors cannot enter the market is written as Lemma 2. Lemma 2. The settlement market cannot exist, if the following condition is satisfied u '(W Q*) q * F (q*) q* u '(W y p1 D ) qf (q)dq 0 where Q* p1D R * Proof. (9) By Proposition 1, S* p1D when (9) is satisfied. // Lemma 2 indicates that if condition (9) is satisfied, then the marginal benefit is still greater than the marginal cost at p1 D . As a result, the optimal surrender value is greater than the settlement price. Based on this observation, we hereafter focus on the case in which S* < p1 D . Now, suppose that the settlement market exists. If the insurer sets the surrender value below p1 D , then no policyholder will surrender the policy. Once the policy is settled, the insurance contract is alive and its actuarial value is p1 D . Therefore, the insurer’s profit is the same as the case in which no policyholders choose surrender. On the other hand, the insurer can set the surrender value higher than the settlement price to block the entry of settlement investors strategically. However, the following lemma shows that the optimal surrender value should be equal to the settlement price p1 D . Lemma 3. Suppose a competitive settlement market. less than the settlement price. Then, the optimal surrender value is Proof. See the Appendix.// When no settlement market exists, a low surrender value is needed to smooth the income stream, which allows the insurer to extract a rent. The introduction of a settlement market restricts the insurer’s extraction. To cope with investors, the insurer has to increase the surrender value up to the settlement price. 3. Target liquidity risk By Lemma 3, the premium can be expressed as follows. Qs p1D Rs (10) As in Section III, the net benefit of the policyholder with target risk qs equals zero. obtain the following expression. We NBqs u(W Qs ) qu(W y p1D) (1 qs ) p1v(D) (1 p1 )(1 qs )u(W1 ) [u(W ) qsu(W y) (1 p1 )(1 qs )u(W1 )] 0 (11) We also have the following result from (11) and (2). u(W Qs ) qsu(W y p1D) qs p1v(D) qsu(W y) u(W Q*) q * u(W y S*) q * p1v(D) q * u(W y) (12) As in Proposition 1, the optimal target risk qs* solves the following problem. Max s ( Rs (qs ), qs ) qs Rs F (qs ) s.t. u(W Qs ) qsu(W y p1D) (1 qs ) p1v(D) (1 qs )(1 p1 )u(W1 ) [u(W ) qsu(W y) (1 p1 )(1 qs )u(W1 )] 0 where Qs p1D Rs (13) Proposition 2. The optimal target liquidity risk qs * and Rs * are determined as follows. Rs f (qs ) [ p1v( D) u (W y ) u (W y p1D)] u '(W Qs ) Proof. See the Appendix.// F ( qs ) (14) Note that (14) is the same as (5) with the additional constraint that the surrender value is equal to p1 D . The interpretation of (14) is similar to (5). The insurer determines qs * where marginal revenue equals marginal cost. As a result, the existence of a settlement market leads the insurer to choose ( Ss * p1D, qs *, Rs * ), instead of the original optimal contract ( S*, q*, R * ). 4. Consumer welfare and social welfare Now, consumer welfare CWs and social welfare SWs can be expressed as follows: CWs u(W Qs *) F (qs *) u (W y p1D) qf (q)dq p1v( D) (1 q) f (q)dq qs * qs * 0 0 u(W ) F (qs *) u(W ) (1 q) f (q)dq qs * 0 [qs * F (qs *) qs * SWs [qs * F (qs *) qs * 0 0 qf (q)dq][ p1v( D) u(W y) u(W y p1D)] (15) qf (q)dq][ p1v( D) u (W y) u (W y p1D)] Rs * F (qs *) (16) As in the basic model, the policyholder with liquidity risk lower than target risk qs* enjoys the positive net benefit. This implies that consumer welfare is positive. V. Effects of the life settlement market Let us analyze the effects of the settlement market on the insurance contract. By comparing cases with and without the settlement market, we obtain the following results. Proposition 3. The monopolistic insurer's profit is lower when the settlement market exists. Proof. The existence of the settlement market effectively imposes additional constraint (S = p1D) on the insurer. That is, the insurer should solve the profit maximization problem under an additional constraint. Therefore, the profit should be smaller when a settlement market exists. We have: ( R(S (q*), q*), S (q*), q*) s s ( Rs (qs *), qs *) (17) Equality holds only when S* equals p1D. // Comparative statics analyses are performed to investigate the effects of the settlement market on the insurance contract. To examine the effects on the contract, we take the total differentiation of the first order conditions when there is no settlement market. With Proposition 3, we can show that the rent is lower when the settlement market exists, which implies that the monopsony power of the insurer is reduced. We also find that the premium is higher. These observations are summarized in Proposition 4. Proposition 4. Suppose that the settlement market exists. Comparing with the case with no settlement market, we have the following results. (1) The premium is higher. (2) The insurer’s rent per premium is lower. (3) The target liquidity risk can be increased even though the premium is higher. Proof. See the Appendix.// From Propositions 3 and 4, we know that the insurer’s profit and monopoly power are lowered when the settlement market is introduced. This can be interpreted as resulting from competition between the insurer and the settlement market. While the rent is lower, the premium is always increased. This is because the insurer adjusts the premium to reflect the higher surrender value as well as to compensate for the loss. When the premium increases, the income gap between t=0 and t=1 is higher, so the net benefit of a consumer who has low liquidity risk is decreased. However, the increase in the surrender value leads the improvement in net benefit for the consumer who has high liquidity risk. As a result, even though the premium increases, more policyholders can buy insurance. Demand can decrease as well when the premium is too high. The sign of demand change depends on the utility shape and the wealth level of the policyholders. These factors affect the insurer’s profit. In this case, the population distribution is also important since it affects the revenue of the insurer. Since the insurer selects the target risk to maximize its profit, the target risk can be greater or smaller according to the premium change compared with the case where there is no settlement market. VI. Welfare comparison By comparing welfare with and without the settlement market, we have proposition 5. Proposition 5. Suppose that the settlement market exists. Comparing with the case with no settlement market, (1) consumer welfare is higher if the the following condition is satisfied: [qs * F (qs *) qs * 0 q* qf (q)dq] [q * F (q*) qf (q)dq] [ p1v( D) u (W y ) u (W y S *)] [ p1v( D) u (W y ) u (W y p1D)] (18) 0 (2) social welfare can be higher when the increase in consumer welfare is greater than the decrease in the insurer’s profit. Proof. See the Appendix.// From Proposition 5, it is evident that the introduction of settlement market can increase consumer welfare. Consumer welfare is improved when the target risk sufficiently increases, even if the premium is increased. This result is illustrated in Figure 2. On the other hand, if qs* is smaller than q*, then consumer welfare can decrease. This result is depicted in Figure 3. The effect on social welfare is not clear. While the insurer’s profit always decreases, consumer welfare can increase or decrease. If consumer welfare decreases, then social welfare decreases as well. However, if consumer welfare increases enough to offset the profit decrease, then it is possible that social welfare increases. VII. Numerical example Let us suppose that the population of policyholders over liquidity risk has uniform distribution with [0,1]. In addition, we assume that the utility function is u(W ) 1000exp(aW ) and v(W ) 1,000[1 exp(aW )] . We impose the initial value as W 20, D 12, a 0.3, y 20, p1 0.2 and find the optimal contract. We first identify that there are cases where a settlement market can exist and cannot exist when parameters a, y and p1 change2. These results are illustrated in Figures 4, 5, and 6, and Table 1,2, and 3. These results can be explained intuitively. At first, if the policyholders are more risk averse, they gain more benefit when the premium is lower due to the lower surrender value, because the income at t = 0 and t = 1 would be smooth. The insurer can extract this rent imposing low surrender value. Second, when the income shock is higher, people would like to get the higher surrender value to smooth the income between t = 0 and t = 1. Finally, as death probability increases, the policyholder seeks lower surrender value and premium to increase the utility at t = 0, that the policyholder is certainly alive. As a result, these results are attributed that the insurer would like to increase the net benefit it extracts. Next, we show that consumer and social welfare can be enhanced as in this numerical example. In addition, we infer that consumer welfare would be decreased as risk aversion increases when a settlement market is introduced. This is because the target policyholders prefer low surrender value as in Figure 4. The increase in surrender value caused by introducing the settlement market lowers the increase in consumer welfare and furthermore decreases consumer welfare. Similarly, we anticipate that consumer welfare declines as the income shock and death probability increase. We can elaborate this conjecture by comparing welfare and demand when the settlement market can exists. We also observe that there exists a case where social welfare is deteriorated even though the market is deep. In this example, the target liquidity risk, demand, increases and the premium is higher, so the market size is larger, but welfare is lower. This is contrary to the general belief that as the market deepens, welfare is enhanced. These results are depicted in Figure 7,8, and 9, and Table 4,5, and 6. Demand always increases in the above example. However, there are other examples in which the demand decreases and consumer welfare also decreases, or where consumer welfare decreases even if demand increases by changing the death benefit. The premium is higher when the death benefit increases, so optimal surrender value decreases to smooth intertemporal consumption. In addition, we already see that if the optimal surrender value without a settlement market is higher, then the net benefit difference with a settlement market decreases in (7) and (15). As a result, as the death benefit increases, consumer welfare tends to worsen. Demand decreases following the difference in net benefit becoming larger. Policyholders cannot buy the insurance because the premium is too high. These results are shown in Figure 10 and Table 7. Moreover, we show how the result depends on the population distribution. We can observe that if the density function of population is an increasing function, then consumer 2 We used MATLAB R2014a and ran 1,000 times optimization in each case. welfare also increases more. Conversely, if the density function is decreasing function, then the consumer welfare decreases. Demand is higher in all cases. However, change in demand is greater when the density function is decreasing. The changes are depicted in Table 8. Hence, we obtain that with sufficient increased demand, consumer welfare and social welfare increase following the population distribution after a settlement market is introduced. VIII. Comparison with competitive insurance market Now, we consider a competitive insurance market. We suppose that q is distributed on [0,1] and the mean value of q is . All other assumptions are identical to that of monopolistic insurance market. In this case, the insurer’s expected profit should be zero. In a competitive equilibrium without a settlement market, premium and surrender value must maximize consumer welfare. In addition, insurers sell the insurance to all consumers to maximizing consumer welfare. The problem can be written as: Max CW u (W Q ) u (W y S ') p1 (1 )v ( D ) (1 p1 )(1 )u (W y ) Q,S u (W ) u (W y ) (1 p1 )(1 )u (W y ) s.t. Q S ' p1D(1 ) S 0 (19) We obtain optimal surrender value by solving (19). When a settlement market does not exist, optimal surrender value is zero for consumption smoothing when income shock y is lower than premium. However, if y is higher than premium, positive surrender value is possible. Now, we suppose that the optimal surrender value without settlement market is lower than p1 D . If the surrender value is higher than p1 D , then settlement investors have not incentive to enter the market. In this case, welfare does not change. If a settlement market is introduced, surrender value is increased at p1 D and consumer welfare is reduced. This is because the premium increases when surrender value increases, so policyholders cannot smooth the income between t=0 and t=1. This result is summarized in Lemma 4. Lemma 4. In a competitive insurance market, we obtain following results. (1) Without a settlement market, optimal surrender value is equal to zero when income shock is higher than the premium. Otherwise, surrender value has a positive value. (2) When a settlement market is introduced, consumer welfare is deteriorated. Proof. See the Appendix.// We know that the non-discriminatory contract design based on liquidity risk derives the consumer welfare improvement in monopolistic insurance markets in contrast with competitive insurance markets. IX. Discussion Our research distinguishes itself from earlier studies in several respects. First, we consider the heterogeneous liquidity risk of policyholders. Policyholders may surrender or settle their policies for cash. The liquidity risk consideration reflects the fact that the settlement market has been introduced to help terminally-ill people pay for medical treatment. Our approach differs from Seog and Hong (2012) because they consider only homogeneous liquidity risk. Note that, in DHL and FK, the main reason for surrender is disappearance of the bequest motive. Second, we focus on a monopolistic insurer, unlike DHL, FK and Hong and Seog (2012) who all consider competitive insurance markets. Focusing on a monopolistic insurer enhance our understanding of the settlement market. The effects of the settlement market differ significantly from the competitive case, as shown in our analysis. In the competitive insurance market, consumer welfare and social welfare are never increased by the introduction of the settlement market. However, our analysis shows that welfares can increase. Our result depends not only on the monopoly condition but also on nondiscriminatory contract design based on liquidity risk. Third, we consider a population distribution, while DHL, FK and Hong and Seog consider the representative consumer. Different potential policyholders may have different willingness to pay for an insurance contract. X. Conclusion We analyze the effects of life insurance settlement on insurer’s profit and consumer and social welfare. We consider a one-period model in which the insurance market is monopolistic and the settlement market is competitive. Policyholders face heterogeneous liquidity risk in addition to mortality risk. Liquidity risk is introduced to address the case in which policyholders need urgent cash, leading them to surrender or settle policies. It is assumed that the insurer cannot observe liquidity risk nor discriminate among policyholders based on liquidity risk. It is further assumed that no costs are incurred in policy surrender or settlement. We find that the introduction of a life settlement market lowers monopolistic rent and profit. In addition, premium increases. The effects on consumer welfare and social welfare are mixed. Consumer welfare increases only when demand increases sufficiently. This finding implies that social welfare, as measured by the sum of consumer welfare and insurer’s profit, can increase if the increase in consumer welfare is greater than the decrease in insurer's profit. This finding contrasts with the existing literature, in which the settlement market lowers social welfare. Numerical Example. W0 = 20, D = 12, a = 0.3, y = 10, p1 0.2 , u(W ) 1000exp(aW ) , v(W ) 1,000[1 exp(aW )] , q ~ U [0,1] Table 1. Surrender Value when risk aversion changes a S Settlement price 0.2 4.9384 2.4 0.22 4.7570 2.4 0.24 3.5290 2.4 0.26 2.9784 2.4 0.28 2.4666 2.4 0.3 1.9923 2.4 0.32 1.5532 2.4 0.34 1.1464 2.4 0.36 0.7689 2.4 0.38 0.4179 2.4 0.4 0.0908 2.4 Table 2. Surrender Value when income shock changes a S Settlement price 8 0.2601 2.4 8.2 0.4349 2.4 8.4 0.6094 2.4 8.6 0.7836 2.4 8.8 0.9576 2.4 9 1.1312 2.4 9.2 1.3044 2.4 9.4 1.4772 2.4 9.6 1.6495 2.4 9.8 1.8212 2.4 10 1.9923 2.4 10.2 2.1627 2.4 10.4 2.3322 2.4 10.6 2.5008 2.4 10.8 2.6683 2.4 11 2.8345 2.4 0.2 1.9923 2.4 0.21 1.8814 2.52 0.22 1.7746 2.64 0.23 1.6716 2.76 0.24 1.5722 2.88 0.25 1.4762 3 0.26 1.3833 3.12 0.27 1.2933 3.24 0.28 1.2061 3.36 0.29 1.1215 3.48 0.3 1.0393 3.6 Table 3. Surrender Value when death probability changes a S Settlement price 0.15 2.6211 1.8 0.16 2.4842 1.92 0.17 2.3533 2.04 0.18 2.2279 2.16 0.19 2.1077 2.28 Table 4.Change in welfare and demand when risk aversion changes a 0.29 0.30 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.40 S* P1D q* qs π πs CW CWs SW SWs △q △CW △SW 2.2249 1.9923 1.7686 1.5532 1.3460 1.1464 0.9542 0.7689 0.5903 0.4179 0.2515 0.0908 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 0.8200 0.8172 0.8153 0.8141 0.8136 0.8136 0.8141 0.8149 0.8161 0.8175 0.8192 0.8210 0.8237 0.8251 0.8266 0.8282 0.8299 0.8317 0.8335 0.8353 0.8372 0.8391 0.8410 0.8430 6.4822 6.6602 6.8381 7.0158 7.1929 7.3692 7.5445 7.7186 7.8914 8.0628 8.2327 8.4009 6.4805 6.6510 6.8161 6.9761 7.1313 7.2820 7.4283 7.5705 7.7089 7.8435 7.9747 8.1025 54.7352 55.8057 56.8372 57.8324 58.7933 59.7219 60.6195 61.4878 62.3279 63.1410 63.9282 64.6905 54.7553 55.8474 56.8924 57.8924 58.8496 59.7661 60.6441 61.4858 62.2932 63.0682 63.8127 64.5285 61.2174 62.4659 63.6754 64.8482 65.9862 67.0911 68.1640 69.2064 70.2193 71.2038 72.1608 73.0914 61.2358 62.4984 63.7085 64.8685 65.9809 67.0481 68.0724 69.0563 70.0020 70.9117 71.7873 72.6310 0.0037 0.0079 0.0113 0.0141 0.0163 0.0180 0.0194 0.0204 0.0211 0.0216 0.0219 0.0220 0.0201 0.0417 0.0552 0.0600 0.0562 0.0442 0.0246 -0.0020 -0.0347 -0.0728 -0.1155 -0.1620 0.0184 0.0325 0.0331 0.0203 -0.0054 -0.0430 -0.0916 -0.1501 -0.2173 -0.2921 -0.3735 -0.4604 Table 5. Change in welfare and demand when income shock changes y S* P1D q* qs π πs CW CWs SW SWs △q △CW △SW 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 0.2601 0.4349 0.6094 0.7836 0.9576 1.1312 1.3044 1.4772 1.6495 1.8212 1.9923 2.1627 2.3322 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 0.7534 0.7573 0.7615 0.7663 0.7715 0.7774 0.7838 0.7909 0.7988 0.8076 0.8172 0.8279 0.8398 0.7724 0.7761 0.7801 0.7844 0.7890 0.7940 0.7993 0.8051 0.8112 0.8179 0.8251 0.8329 0.8413 6.4065 6.4126 6.4221 6.4353 6.4524 6.4739 6.5000 6.5312 6.5679 6.6107 6.6602 6.7170 6.7820 6.2262 6.2562 6.2885 6.3231 6.3602 6.4001 6.4431 6.4893 6.5392 6.5929 6.6510 6.7137 6.7817 53.0438 53.1682 53.3188 53.4981 53.7084 53.9526 54.2338 54.5556 54.9217 55.3368 55.8057 56.3342 56.9288 52.2804 52.5328 52.8035 53.0939 53.4059 53.7411 54.1018 54.4901 54.9085 55.3599 55.8474 56.3746 56.9453 59.4503 59.5808 59.7409 59.9334 60.1608 60.4265 60.7338 61.0867 61.4896 61.9475 62.4659 63.0512 63.7108 58.5066 58.7890 59.0919 59.4170 59.7661 60.1413 60.5449 60.9794 61.4476 61.9528 62.4984 63.0883 63.7270 0.0190 0.0189 0.0186 0.0181 0.0175 0.0166 0.0155 0.0141 0.0124 0.0104 0.0079 0.0050 0.0015 -0.7634 -0.6354 -0.5154 -0.4041 -0.3025 -0.2115 -0.1320 -0.0655 -0.0132 0.0231 0.0417 0.0404 0.0165 -0.9437 -0.7918 -0.6490 -0.5164 -0.3948 -0.2852 -0.1890 -0.1074 -0.0420 0.0053 0.0325 0.0371 0.0163 Table 6. Change in welfare and demand when death probability changes P1 S* P1D q* qs π πs CW CWs SW SWs △q △CW △SW 0.183 0.192 0.201 0.21 0.219 0.228 0.237 0.246 0.255 0.264 0.273 0.282 0.291 0.3 2.1913 2.0843 1.9810 1.8814 1.7851 1.6919 1.6017 1.5142 1.4294 1.3470 1.2669 1.1890 1.1132 1.0393 2.196 2.304 2.412 2.52 2.628 2.736 2.844 2.952 3.06 3.168 3.276 3.384 3.492 3.6 0.8272 0.8216 0.8167 0.8124 0.8085 0.8051 0.8020 0.7992 0.7968 0.7945 0.7925 0.7906 0.7889 0.7874 0.8274 0.8262 0.8250 0.8237 0.8223 0.8209 0.8194 0.8179 0.8163 0.8147 0.8131 0.8115 0.8098 0.8081 6.6089 6.6363 6.6631 6.6892 6.7144 6.7387 6.7619 6.7840 6.8051 6.8250 6.8438 6.8615 6.8781 6.8936 6.6089 6.6335 6.6529 6.6674 6.6776 6.6837 6.6862 6.6852 6.6812 6.6742 6.6646 6.6525 6.6381 6.6216 51.1633 53.6155 56.0801 58.5563 61.0433 63.5402 66.0466 68.5618 71.0854 73.6167 76.1554 78.7011 81.2534 83.8119 51.1644 53.6512 56.1210 58.5732 61.0077 63.4241 65.8223 68.2019 70.5628 72.9048 75.2278 77.5315 79.8158 82.0806 57.7722 60.2518 62.7433 65.2455 67.7577 70.2789 72.8085 75.3459 77.8904 80.4417 82.9992 85.5626 88.1315 90.7056 57.7732 60.2848 62.7738 65.2406 67.6853 70.1078 72.5084 74.8871 77.2440 79.5791 81.8924 84.1840 86.4539 88.7022 1.6546 1.6478 1.6417 1.6360 1.6308 1.6259 1.6214 1.6171 1.6131 1.6093 1.6056 1.6021 1.5987 1.5955 0.0011 0.0357 0.0408 0.0169 -0.0356 -0.1161 -0.2244 -0.3600 -0.5225 -0.7119 -0.9276 -1.1696 -1.4376 -1.7314 0.0011 0.0330 0.0306 -0.0049 -0.0724 -0.1711 -0.3001 -0.4588 -0.6464 -0.8626 -1.1068 -1.3786 -1.6776 -2.0034 Table 7. Change in optimal Surrender value without settlement market, consumer welfare, social welfare and demand when death benefit changes D 11 13 15 17 19 21 23 25 27 29 31 33 35 S* 2.0206 1.9697 1.9354 1.9100 1.8892 1.8708 1.8534 1.8365 1.8196 1.8025 1.7851 1.7672 1.7488 P1D 2.2 2.6 3 3.4 3.8 4.2 4.6 5 5.4 5.8 6.2 6.6 7 q* 0.8191 0.8156 0.8129 0.8105 0.8082 0.8060 0.8038 0.8016 0.7993 0.7970 0.7946 0.7921 0.7895 qs 0.8228 0.8270 0.8295 0.8304 0.8296 0.8271 0.8231 0.8174 0.8101 0.8012 0.7908 0.7788 0.7652 π 6.7372 6.5574 6.4075 6.2291 6.0468 5.8626 5.6773 5.4915 5.3055 5.1195 4.9335 4.7477 4.5621 πs 6.7353 6.5574 6.3490 6.1194 5.8744 5.6177 5.3521 5.0798 4.8028 4.5226 4.2409 3.9590 3.6781 CW 55.3615 56.1044 56.4049 56.4597 56.3769 56.2158 56.0084 55.7722 55.5166 55.2466 54.9646 54.6716 54.3681 CWs 55.3983 56.1052 56.1957 55.8811 55.2789 54.4555 53.4492 52.2830 50.9712 49.5235 47.9469 46.2469 44.4280 SW 110.7597 112.2096 112.6005 112.3407 111.6558 110.6713 109.4576 108.0552 106.4878 104.7701 102.9115 100.9185 98.7961 SWs 166.1580 168.3148 168.7962 168.2218 166.9347 165.1268 162.9068 160.3381 157.4590 154.2936 150.8584 147.1655 143.2242 △q 0.0037 0.0114 0.0167 0.0199 0.0214 0.0211 0.0192 0.0158 0.0108 0.0042 -0.0038 -0.0133 -0.0243 △CW 0.0368 0.0007 -0.2092 -0.5786 -1.0980 -1.7602 -2.5591 -3.4892 -4.5455 -5.7231 -7.0176 -8.4247 -9.9401 △SW 0.0350 0.0007 -0.2677 -0.6883 -1.2705 -2.0051 -2.8843 -3.9009 -5.0482 -6.3199 -7.7102 -9.2134 -10.824 Table 8. Change in welfare and demand following the population density function f(q)=2q f(q)=I(0,1) f(q)=-2q+2 S* CW CWs SW SWs q* qs △CW △SW △q 2.2921 1.9923 0.7503 44.6336 55.8057 45.4786 44.7817 55.8474 43.9963 50.7151 62.4659 60.1875 50.6959 62.4984 58.6704 0.9331 0.8172 0.5585 0.9356 0.8251 0.5761 0.1481 0.0417 -1.4823 -0.0193 0.0325 -1.5171 0.0025 0.0079 0.0176 Figure 1. Time line of model t=1 t=0 Insurance is purchased and premium Q paid. Liquidity needs occur Surrender value S is paid with pr. q or settlement occurs with price p1 D A loss occurs and insurance benefit D paid with pr. p1 Figure 2. Case that consumer welfare can be improved Net benefit NB NBs q* non-existence of settlement market qs q existence of settlement market Figure 3. Case that consumer welfare is deteriorated Net Benefit NB NBs qs q* q non-existence of settlement market existence of settlement market Figure 4. Change of surrender value when risk aversion a changes 5 S settlement market cannot exist 4 3 settlement market can exist 2 1 a 0 0.224 0.244 0.264 0.284 0.304 0.324 0.344 0.364 0.384 Figure 5. Change of surrender value when income shock y changes 3 S settlement market cannot exist 2.5 2 settlement market can exist 1.5 1 0.5 y 0 8 8.25 8.5 8.75 9 9.25 9.5 9.75 10 10.25 10.5 10.75 11 Figure 6. Change of surrender value when death probability p1 changes 3.00 S settlement market 2.50 cannot exist settlement market 2.00 can exist 1.50 1.00 0.50 p1 0.00 0.15 0.17 0.19 0.21 0.23 0.25 0.27 0.29 Figure 7. Change in consumer welfare, social welfare and demand when risk aversion a changes △CW 0.10 0.05 a 0.00 -0.05 0.29 0.3 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.4 -0.10 -0.15 -0.20 △q 0.0250 0.0200 0.0150 0.0100 0.0050 a 0.0000 0.29 0.3 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 △SW 0.10 a 0.00 -0.10 -0.20 -0.30 -0.40 -0.50 0.29 0.3 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 Figure 8. Change in consumer welfare, social welfare and demand when income shock y changes △CW 0.2 y 0.0 -0.2 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 -0.4 -0.6 -0.8 -1.0 △q 0.02 0.02 0.01 0.01 y 0.00 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 △SW 0.2 y 0.0 8 -0.2 -0.4 -0.6 -0.8 -1.0 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 Figure 9. Change in consumer welfare, social welfare and demand when death probability p1 changes △CW 0.5 P1 0 0.18 0.19 0.20 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 -0.5 -1 -1.5 -2 △q 0.025 0.020 0.015 0.010 0.005 P1 0.000 0.18 0.19 0.20 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 △SW 0.5 P1 0.0 -0.5 -1.0 -1.5 -2.0 -2.5 0.18 0.19 0.20 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 Figure 10. Change in optimal surrender value without settlement market, consumer welfare, social welfare and demand when death benefit changes S 2.10 2.00 1.90 1.80 1.70 D 1.60 11 14 17 20 23 26 29 32 35 △CW 2 D 0 -2 -4 -6 -8 -10 -12 11 14 17 20 23 26 29 32 35 △q 0.03 0.02 0.01 0.00 -0.01 11 14 17 20 23 26 29 32 35 -0.02 -0.03 △SW 2.0 D 0.0 -2.0 -4.0 -6.0 -8.0 -10.0 -12.0 11 14 17 20 23 26 29 32 35 References Daily, Glenn, Igal Hendel and Alessandro Lizzeri (2008), Does the Secondary Life Insurance Market Threaten Dynamic Insurance?, American Economic Review 98 (2): 151-156. Doherty, N. A. and Singer, H. J. (2003), The Benefits of a Secondary Market for Life Insurance Policies, Real Property, Probate and Trust Journal : 449-478.. Fang, Hanming and Edward Kung (2008), How Does the Life Settlement Affect the Primary Life Insurance Market?, Working Paper, Department of Economics of Duke University. Gatzert, Nadine (2010), The Secondary Market for Life Insurance in the United Kingdom, Germany, and the United States: Comparison and Overview, Risk Management and Insurance Review 13(2): 279–301. Gatzert, Nadine, Gudrun Hoermann and Hato Schmeiser (2008), The Impact of the Secondary Market on Life Insurers' Surrender Profits, Working Papers on Risk Management and Insurance 54, University of St. Gallen. Hendel, Igal and Alessandro Lizzeri (2003), The Role of Commitment in Dynamic Contracts: Evidence from Life Insurance, Quarterly Journal of Economics 118 (1): 299-327. Hong, Jimin and S. Hun Seog (2012), A Study of the Effect on the Life Insurance Market of Life Settlement, Korean Insurance Journal 95 : 23-50. Seog, S. Hun and Jimin Hong (2012), A Study on the Introduction of Life Settlement based in Monopoly Insurance Market, The Journal of Risk Management 23 (2) : 1-34. Appendix 1. Proof of Lemma 1. Lemma 1. Potential policyholders with lower liquidity risk than the target liquidity risk purchase insurance. Proof. If net benefit is greater than 0, potential policyholders with liquidity risk q ' will buy insurance contracts. Thus we have 0 NB(q) NB(q ') u(W Q) qu(W y S ) (1 q) p1v(D) u(W ) qu(W y) u(W Q) q ' u(W y S ) (1 q ') p1v( D) u(W ) q ' u(W y) (A.1) From this relation, we obtain the following. (q ' q) [u(W y S ) p1v( D) u(W y)] 0 (A.2) In (A.2), u(W y S ) [ p1v( D) u(W y)] , because of the assumption that without liquidity risk, the utility of keeping the insurance contract is higher than that of surrender. Therefore, q q ' must be satisfied for equation (A.2). // 2. Proof of Proposition 1. Proposition 1. The optimal surrender value S *, R * and q * are satisfying (4) and (5). q' u '(W Q) qf (q)dq qF (q)u '(W y S ) (4) 0 Rf (q) [ p1v( D) u (W y) u (W y S )] u '(W Q ') F (q ) (5) where Q ' q ' S (1 q ') p1D R ' Proof. We can find the optimal S *, R * and q * using the Lagrangian optimization, where λ is the Lagrange multiplier. L [ S p1D][q ' F (q ') 0 qf (q)dq] RF (q ') q' (q ')[u(W Q ') q ' u(W y S ) (1 q ') p1v(D) u(W ) q ' u(W y)] (A.3) The first order conditions for an optimum with respect to S, R, and λ are as follows. LS [q ' F (q ') qf (q)dq] (q ') q '[u '(W Q ') u '(W y S )] 0 q' 0 LR F (q ') (q ')u '(W Q ') 0 Lq [ S p1D]F (q ') Rf (q ') (A.4) (A.5) (q ')[( S p1D)u '(W Q ') u(W y S ) p1v(D) u(W y)] 0 L u(W Q ') q ' u(W y S ) (1 q ') p1v( D) u(W ) q ' u(W y) 0 (A.7) (A.6) By (A.5) we have, (q ') F (q ') u '(W Q ') (A.8) Let us plug (A.8) into (A.4) and (A.6). Now, the first order conditions can be simplified as q' u '(W Q) qf (q)dq qF (q)u '(W y S ) 0 and Rf (q) [ p1v( D) u (W y) u (W y S )] u '(W Q ') F (q) // In equilibrium, the premium is Q* q * S * (1 q*) p1D R * , so the marginal revenue with respect to q is as follows. [ S * p1D]F (q*) [ q * S * (1 q*) p1D R*] f (q*) (A.9) In (A.9), [ S * p1D]F (q*) is the marginal revenue from existing policyholders, and [ q * S * (1 q*) p1D R*] f (q*) is the marginal revenue from new policyholders. Meanwhile, marginal cost when q increases and is the shadow price is as follows. [ q * S * (1 q*) p1D] f (q*) [( S * p1D)u '(W Q*) p1v(D) u(W y) u(W y S*)] (A.10) In (A.10), the insurer needs to pay [ q * S * (1 q*) p1D] f (q*) more when q increases because of the increase in surrender or death benefit for new consumers. This is the cost for the insurer. On the other hand, the insurer extracts the net benefit from policyholders with liquidity risk q* until the net benefit is equal to zero. If q increases, the net benefit the insurer can extract changes as below: dNB(q*) Q * dNB(q*) NB(q*) dq * q * dQ * q * ( S * p1D)u '(W Q*) [ p1v( D) u(W y) u(W y S*)] (A.11) The insurer should give up the increase in net benefit following the premium decrease caused by an increase in q from existing policyholders by as much as ( S * p1D)u '(W Q*) . On the contrary, the insurer can obtain the net benefit of as much as [ p1v( D) u(W y) u(W y S*)] from consumers because of an increase in q. As a result, for the insurer, {( S * p1D)u '(W Q*) [ p1v(D) u(W y) u(W y S*)]} is the additional cost for the increase in q. Total marginal cost for q is as follows. [ q * S * (1 q*) p1D] f (q*) [ p1v( D) u (W y ) u (W y S *)]F (q*) [( S * p1D)]F (q*) u '(W Q*) (A.12) (A .13) should be satisfied such that marginal cost equals marginal revenue to maximize insurer’s profit: [ S * p1D]F (q*) [ q * S * (1 q*) p1D R*] f (q*) [ q * S * (1 q*) p1D] f (q*) [( S * p1D)]F (q*) [ p1v( D) u (W y ) u (W y S *)]F (q*) u '(W Q*) (A.13) That is rearranged as below and it is equivalent to (A.9) R * f (q*) [ p1v( D) u (W y ) u (W y S *)] F (q*) u '(W Q*) That is, optimal q is determined at the point that marginal cost equals marginal revenue of q.// 3. Proof of Lemma 3. Lemma 3. Suppose a competitive settlement market. less than the settlement price. Then, the optimal surrender value is Proof. Let us suppose that the premium Q ' is as follows, given the optimal target liquidity risk q ' , when the settlement market exists. Q ' q ' S (1 q ') p1D R (A.14) Thus the profit maximization problem can be stated as follows. Max ( R( S ), S ) S Q ' F (q) S qf (q)dq p1D (1 q) f (q)dq q' q' 0 0 [ S p1D][q ' F (q ') q ' f (q ')dq] RF (q ') q' 0 s.t. u(W Q ') q ' u(W y S ) (1 q ') p1v( D) (1 q ')(1 p1)u(W y) [u (W ) q ' u (W y) ( 1 q ' )1 ( 1p u ) W( y ) ] 0 S p1 D (A.15) The Lagrangian becomes L [ S p1D][q ' F (q ') qf (q)dq] RF (q ') q' 0 (q ')[u(W Q ') q ' u(W y S ) (1 q ') p1v(D) u(W ) q ' u(W y)] [ p1D S ] where 0 (A.16) For S ' , the first order condition is LS ' [q ' F (q ') qf (q)dq] q' 0 (q ') q '[u '(W Q ') u '(w y S ')] 0 (A.17) We define that LS LS (q*, S*) 0 in (A.4). If we assume that optimal q * and S * are unique, then, for q ' , LS (q ', S ') 0 . This is because q* and S* do not satisfy the additional constraint S ' p1D . Thus, for q ' and S ' , LS ' should be negative and LS ' LS (q ', S ') 0 . As a result, should be positive to satisfy (A.17) and we have p1D S ' 0 by complementary slackness condition [ p1D S '] 0 . // 4. Proof of Proposition 2. Proposition 2. The optimal target liquidity risk qs * and Rs * are determined as follows. Rs f (qs ) [ p1v( D) u (W y ) u (W y p1D)] u '(W Qs ) F ( qs ) (14) Proof. The Lagrangian is written as Ls Rs F (qs ) (qs )[u(W Qs ) qsu(W y p1D) (1 qs ) p1v(D) u(W ) qsu(W y)] (A.18) The first order condition is obtained as follows. Lqs Rs f (qs ) (qs )[ u(W y p1D) p1v( D) u (W y)] 0 LRs F (qs ) (qs )u '(W Qs ) 0 (A.19) (A.20) Ls u (W Qs ) qsu (W y p1D) (1 qs )v( D) u (W ) qsu (W y ) 0 (A.21) From (A.19) to (A.21), the optimal qs* and Rs* should satisfy the following condition. Rs f (qs ) [ p1v( D) u (W y ) u (W y p1D)] u '(W Qs ) F ( qs ) (A.22)// 5. Proof of Proposition 4 Proposition 4. Suppose that the settlement market exists. Comparing with the case with no settlement market, we have the following results. (1) The premium is higher. (2) The insurer’s rent per premium is lower. (3) The target liquidity risk can be increased even though the premium is higher. Proof. (1) We know that if dq* < 0 then dQ* > 0. Let us assume q* qs * and Q* Qs * . Then, by (12), we obtain following relation (A.23) and it is a contradiction, so in case of q* qs * , Q* Qs * is true. u(W Q*) q * u(W y S*) (1 q*) p1v( D) q * u(W y) u(W Q*) p1v(D) q *[ p1v(D) u(W y) u(W y S*)] u(W Q*) p1v( D) qs [ p1v( D) u(W y) u(W y S*)] u(W Q*) qs * u(W y S*) (1 qs *) p1v(D) qs * u(W y) u(W Qs *) qs * u(W y p1D) (1 qs *) p1v(D) qs * u(W y) u(W Qs *) qs * u(W y p1D) (1 qs *) p1v(D) qs * u(W y) (A.23) dq * dQ * is increased following relation 0 , the sign of dS * dS * Qs * Q* ( p1D Rs *) ( q * S * (1 q*) p1D R*) Meanwhile, for the case of ( Rs * R*) q *( p1D S*) dQ* dR * q * dS * (A.24) Frrom (A.23) and (A.24), we know that the premium is always increased. (2) (a) f '(q*) 0 From the first order condition (5), we obtain the following relation. DdS* EdR * Fdq * (A.25) where D q * u ''(W Q*) [ p1v( D) u(W y) u(W y S*)] u '(W Q*)2 F (q*) u '(W y S *) F (q*) 0 u '(W Q*) [ p1v( D) u (W y ) u (W y S *)]u ''(W Q*) E f (q*) F (q*) 0 u '(W Q*)2 [ p1v( D) u (W y ) u (W y S *)] F R * f '(q*) f (q*) u '(W Q*) [ p1v( D) u (W y ) u (W y S *)][ p1D S *]u ''(W Q*) F (q*) u '(W Q*)2 If we assume that f '(q*) 0 , then the sign of F in (A.25) is positive. By (A.25), we obtain D > 0, E < 0, and F > 0. From this information, let us investigate the sign of dR* and dq*, when dS* > 0. We can know that the case of dS* > 0, dR* > 0 and dq* < 0 is contradicted by (A.25) because the LHS of (A.25) is positive but the RHS is negative. In addition, from (17), [ S * p1D][q * F (q*) qf (q)dq] R * F (q*) s Rs * F (qs *) should be satisfied. q* 0 This implies R * F (q*) Rs * F (qs *) , because S p1D by Lemma 2. If dq is positive then F(qs* ) > F(q* ), so Rs* should be decreased. Therefore, we can exclude the case in which dq* > 0 and dR* > 0. As a result, only two cases are possible: (i) dR* < 0, dq* > 0 and (ii) dR* < 0, dq* < 0. That is, the rent should decrease. (b) f '(q*) 0 Let us compare (5) and (14). If dS* > 0 then, [ p1v( D) u(W y) u(W y S*)] [ p1v( D) u(W y) u(W y p1D)] , and u '(W Qs *) u '(W Q*) because F (q) is an increasing function in q. As a Qs * Q * by (1) of Proposition 4. In addition, f (q ) result, even if f '(q*) 0 , R should be decreased. As a result, the insurer’s monopolistic power weakens with the introduction of a settlement market. // (3) By (2), we know that dq* can be positive. // 6. Proof of Proposition 5 Proposition 5. Suppose that the settlement market exists. Comparing with the case with no settlement market, (1) consumer welfare is higher if the the following condition is satisfied: [qs * F (qs *) qs * 0 q* qf (q)dq] [q * F (q*) qf (q)dq] [ p1v( D) u (W y ) u (W y S *)] [ p1v( D) u (W y ) u (W y p1D)] (18) 0 (2) social welfare can be higher when the increase in consumer welfare is greater than the decrease in the insurer’s profit. Proof. (1) First, we obtain (A.26) by (7) and (15). CWs CW [qs * F (qs *) qs * 0 q* qf (q)dq][ p1v( D) u(W y) u(W y p1D)] [q * F (q*) qf (q)dq][ p1v( D) u (W y) u (W y S *)] 0 In addition, when q* qs , (A.27) should be satisfied. 1 qs * 1 q* qf ( q ) dq F ( q *) qf (q )dq qs * 0 q * 0 1 q* 1 q* 1 qs * F (qs *) F (q*) qf (q)dq qf (q )dq qf (q)dq 0 0 q* qs qs * q* F (qs *) (A.26) qs * 1 1 qs * 1 qs * [qs * F (q*) qs * F (qs *) qf (q)dq] qf (q)dq qf (q)dq q* qs * qs * 0 qs * 0 q* q* 1 (A.27) [q * qf (q)dq qf (q)dq] 0 qs * qs * q* As a result, the condition for CWs CW 0 is as follows. [qs * F (qs *) qs * 0 q* qf (q)dq] [q * F (q*) qf (q)dq] [ p1v( D) u (W y ) u (W y S *)] [ p1v( D) u (W y ) u (W y p1D)] 0 (2) The sign of the difference in social welfare is not clear: SWs SW [qs * F (qs *) qf (q)dq][ p1v( D) u(W y) u(W y p1D)] qs * 0 q* [q * F (q*) qf (q)dq][ p1v( D) u (W y) u (W y S *) ( p1D S *)] 0 Rs * F (qs *) R * F (q*) (A.28) However, if consumer welfare is sufficiently increased, social welfare can also be increased.// 7. Proof of lemma 4 Lemma 4. In a competitive insurance market, we obtain following results. (1) Without a settlement market, optimal surrender value is equal to zero when income shock is higher than the premium. Otherwise, surrender value has a positive value. (2) When a settlement market is introduced, consumer welfare is deteriorated. Proof. (1) In a competitive insurance market, q=1 because insurers sell life insurance to all consumers. We use Lagrangian maximization where and are Lagrange multiplier. L u(W Q) u(W y S ') p1v( D)(1 ) u(W ) u(W y)(1 ) (A.29) [Q S ' p 1 D( 1 ) ] S 0 should be satisfied for the complementary slackness condition. first order conditions are as follows. Ls u '(W y S ') 0 LQ u '(W Q) 0 Rearranging (A.30) and (A.31), we obtain (A.30) (A.31) For S and Q, the (A.32) This condition means that if y Q , then S > 0. On the other hand, S > 0 when y Q . u '(W y S ') u '(W Q) (2) If the settlement market is introduced, the insurer faces the additional constraint that S p1D . As a result, consumer welfare decreases. //
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