XI Congreso Internacional de la Academia de Ciencias Administrativas A.C. (ACACIA) Tema: Finanzas y Economía

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1 XI Congreso Internacional de la Academia de Ciencias Administrativas A.C. (ACACIA) Tema: Finanzas y Economía Pablo Camacho Gutiérrez, Ph.D. College of Business Administration Texas A&M International University 5201 University Blvd. Laredo, TX USA pcamacho@tamiu.edu Teléfono: ( ) Fax: ( ) Vanessa M. González Cantú, M.Sc. Facultad de Comercio, Administración y Ciencias Sociales Universidad Autónoma de Tamaulipas vmontserrat@uat.edu.mx Guadalajara, Jalisco, México Mayo 2007

2 Abstract. This paper extends Wheelock and Kumbhakar s (1995) test for moral hazard in the Kansas deposit insurance system. This paper tests and finds evidence of omitted unobserved bank effects. As a result, Wheelock and Kumbhakar (1995) (i) failed to find the significant negative effect that bank insurance membership had on bank surplus/loans ratio and (ii) overestimated the effect that bank insurance membership had on bank capital/assets ratio. That is, once the test for moral hazard includes bank heterogeneity, it renders more evidence that the Kansas insurance system suffered from moral hazard. JEL classification: G21, G28, C33, C35. Keywords: deposit insurance, moral hazard test, panel data, random and fixed effects. Acknowledgements: We want to thank David C. Wheelock and Subal C. Kumbhakar for allowing access to the database they used in their paper. This paper begun as a class project that Camacho did for an Econometrics course (taught by Professor Paul Wilson) at The University of Texas at Austin while he was in Graduate School. All errors are ours.

3 1. Introduction. This paper extends Wheelock and Kumbhakar s (1995) paper W&K henceforth by introducing unobserved individual heterogeneity to their test for moral hazard in the Kansas deposit insurance system. This is a natural extension to W&K, because there is some evidence i.e., Wheelock and Wilson (1995) that suggests that W&K might have omitted variables that convey bank specific information. In fact, this paper tests and finds evidence of unobserved heterogeneity across banks. W&K s estimates, as a result, would be biased. Once the test for moral hazard accounts for bank specific effects, it renders more evidence that the Kansas insurance system suffered from moral hazard; e.g., it reinforces W&K s conclusions. This paper, being an extension of W&K, contributes to have a better understanding of the effect of the federal deposit insurance system on the failures of banks and Savings and Loans institutions. W&K falls within the literature that was developed to explain the causes of the large number of banks and S&L failures that occurred in the 1980s Calomaris (1989), Grossman (1992), Wheelock and Wilson (1995), among others. It has been argued that, besides other factors like increased competition and liability deregulation, the federal deposit insurance system played a role in those failures. That is, the federal deposit insurance system might have subsidized banks risk taking behavior. The issue is, then, whether insured banks take more risk that they would otherwise. 1

4 It is hardly possible to contrast the behavior of insured against uninsured banks nowadays, because the FDIC insures most banks in the nation. Instead, W&K analyzed the Kansas deposit insurance system at the beginning of the twentieth century. The Kansas system is interesting because of its unique regulation aimed at mitigating both adverse selection and moral hazard problems. Also, voluntary membership characterized the Kansas system, which allows for contrasting the behavior between insured and uninsured banks. 1 W&K tested for adverse selection and moral hazard in the Kansas deposit insurance system. W&K found evidence supporting the hypothesis that the Kansas system suffered from adverse selection. In contrast, as it is explained below, W&K found evidence of moral hazard for one out of four financial ratios that were used as proxy for banks risk taking behavior. This paper focuses on the moral hazard test only. The remaining of the paper is divided as follows. Section 2 discusses the moral hazard test. Section 3 discusses estimation results. Section 4 concludes. 2. Moral Hazard Test. A test for moral hazard in a deposit insurance system involves contrasting the risktaking behavior of insured versus uninsured banks. Moral hazard would be present in a deposit insurance system if, after controlling for other factors, insured banks engage in riskier behavior than uninsured banks. An econometric test for moral hazard involves regressing a proxy variable for bank risk taking behavior against a set of exogenous covariates that includes bank insurance membership. However, such regression analysis may suffer from selectivity bias, because risk 1 See W&K for a detailed description of the Kansas deposit insurance system. 2

5 prone banks would be more likely to join the deposit insurance system than conservative banks. In order to address selectivity bias, W&K followed Grossman (1992) two step estimation process: 2 the likelihood of an institution being insured is estimated with a probit in the first stage; the predicted value is then used as a regressor in the second stage, in which moral hazard is estimated with ordinary least squares (OLS). (Grossman, 1992, p.815.) In both stages of the estimation process, like Grossman (1992), W&K implicitly assumed that banks were homogenous but for the set of covariates in the econometric regressions. However, there is evidence that may contradict the assumed homogeneity across banks. Wheelock and Wilson (1995), based on a random sample of state chartered Kansas banks during , found that bank insurance membership and technical efficiency were important determinants of bank failures. Even though Wheelock and Wilson (1995) did not analyze the relationship between bank insurance membership and technical efficiency, they showed that banks in Kansas were non homogenous in technical efficiency. A bank insurance decision may be related to its technical inefficiency. One might expect that deposits would command higher premiums in an inefficient bank than an efficient one ceteris paribus. An inefficient bank, as a result, might find optimal to reduce the premium it pays on its deposits through deposits insurance. W&K did not include banks technical efficiency as a covariate in their probit model. If technical efficiency or other omitted variable are indeed determinants of bank insurance membership, then W&K s probit estimates would be biased. Furthermore, unobserved heterogeneity might be present in the second stage of the estimation 2 Grossman (1992) estimation technique, in turn, follows Heckman (1979). 3

6 process as well. It is the goal of this paper to test whether the inclusion of unobserved heterogeneity improves W&K estimates. The test for moral hazard in the mature Kansas deposit insurance system involves the use of Grossman s (1992) two stage process to estimate equations (1) and (2) below. Equation (1) is estimated as a Probit model to produce the estimate for bank insurance membership, DI, which is then included as a regressor in the least squares estimation of equation (2). DI = 1 f ( Age, DIratio, Bankpop ) (1) R = f 2 ( DI, Age, Bankpop, Rural, Pop, Impacre, Landvalue ) (2) where, R = { capital/as sets, surplus / loans, cash / deposits, loans / assets } Table 1 presents the definition of the variables included in the model. 3 Regional and annual dummy variables are also included in order to control for systematic differences across state regions and time; e.g., the model includes regional and time fixed effects. [Table 1 about here] W&K explain the choice of financial ratios as proxies for bank risk taking behavior and the expected effect of bank insurance status on these, as follows. Option theoretic model of deposit insurance, such as Merton s (1977), predict that banks will find it optimal to maintain lower capital/asset ratios and more risky asset portfolios with insurance than they would in the 4

7 absence of insurance. (Wheelock and Kumbhakar, 1995, p. 196.) The capital/asset ratio is not the only possible risk measure available to us, and we also test whether deposit insurance caused differences across banks in the other financial ratios identified by White (1984) and Wheelock (1992) as useful predictors of bank failure in this area. If moral hazard characterized the Kansas insurance system, we expect to find that insurance system membership had a negative impact on the surplus/loan and cash/deposit ratios of insured banks, and a positive impact on their loans/assets ratios. (Wheelock and Kumbhakar, 1995, p. 197.) As a result, the parameter estimate for DI in equation (2) will determine whether the Kansas deposit insurance system suffered from moral hazard. 3. Estimation Results. As it is discussed in the section 2, it is possible that W&K might have omitted variables. This paper, thus, introduces heterogeneity into W&K estimation process in order to capture some of the bank specific effects that might have been left out. The probit model (1) is estimated using random individual effects, given that the fixed effect probit model renders inconsistent estimates and some incidental parameters may not be estimated Green (2000), Hsiao (2003). 4 Equation (2), on the other hand, is estimated using fixed effects only in order to maintain the OLS estimation procedure in the second stage of the test. 5 3 See W&K for details on the variables. 4 Fixed effects probit model was estimated and tested against the random effect model. According to Hausman specification test, the null hypothesis of random effect cannot be rejected at a ten percent confidence level. Also, the incidental parameter could not be estimated for 104 banks; that is, 416 observations were bypassed. 5 Estimation of equation (2) assuming random bank specific effects does not change the conclusions obtained from 5

8 The following estimation results were obtained for the same data set used in W&K, which includes information for 204 banks for the years 1910, 1914, 1918, and This data set is obtained from a random sample of 212 banks that operated in Kansas from 1910 to 1920; however, it excludes 8 banks that had less than a year open by 1910 since those were not eligible for deposit insurance in that year. Also, the data set excludes those banks that began operations after the deposit insurance system started. Banks that might have opened for the purpose of exploiting the insurance system are thus excluded, and hence our results should understate the extent of adverse selection and moral hazard in the Kansas system. (Wheelock and Kumbakhar, 1995, p. 193.) The software NLOGIT, v , was used to estimate the econometric model. Estimation results for the first stage of the estimation process are reported in table 2, which includes probit and random effect probit estimates, as well as probit estimates reported in W&K for comparison purposes. Both probit and W&K probit are the same model, as a result, they render close estimates. The random effect probit model does not reverse the sign of probit estimates or their statistical significance, although its estimates are significantly larger in absolute value than probit estimates. In fact, according to both likelihood ratio and Hausman tests, one cannot reject the hypothesis that there exist bank specific effects, which were not internalized in W&K s estimation process. Therefore, the random effects probit estimate of bank insurance membership is used in the second stage of the estimation process, which tests for moral hazard. [Table 2 about here] the fixed effect estimation procedure. 6

9 Estimation results for bank risk regressions are reported in table 3, which includes least squares (OLS) and fixed effects (FEM) estimates, as well as the least squares estimates reported in W&K s table 4 (W&K OLS) for comparison purposes. 7 OLS renders the same evidence of moral hazard as W&K: bank insurance membership has a statistically significant effect on the capital/assets ratio, but not on the other financial ratios. However, both F and likelihood ratio tests conclude that the null hypothesis of no fixed effects can be rejected at the one percent confidence level. Therefore, the moral hazard test should be based on FEM results, which conclude that bank insurance membership has a statistically significant effect on both capital/assets and surplus/loans ratios. [Table 3 about here] As one might expect to occur in a deposit insurance system that suffers from moral hazard, the moral hazard FEM regression reports evidence that insured banks in Kansas engaged in more risk taking behavior than uninsured banks. Insured banks, for instance, held a capital/assets ratio that on average was 1.15 percentage points smaller than uninsured banks. 8 In contrast, W&K estimated that insured banks held a capital/assets ratio that on average was 2.81 percentage points smaller than uninsured banks. Similarly, insured banks held a surplus/loans ratio that on average was 1.32 percentage points smaller than uninsured banks W&K report the use of 205 banks. W&K OLS includes the probit estimate of DI as a regressor; in contrast, OLS process includes the random effects probit estimate of DI as a regressor. 8 The average capital/assets ratio for all banks is percent. 9 The average surplus/loans ratio for all banks is 8.91 percent. 7

10 In contrast, W&K found no significant effect of bank insurance membership on bank surplus/loans ratio. On the other hand, like W&K, this paper finds no evidence that bank insurance membership was a determinant of bank cash/deposit and loans/assets ratios. 4. Concluding Remarks. This paper extends Wheelock and Kumbakhar s (1995) test for moral hazard in the Kansas deposit insurance system. Thus, this paper contributes to have a better understanding of the perverse incentive effects that the federal deposit insurance system might have on banks and savings & loans institutions. The Kansas deposit system offers a historic experiment to contrast the behavior of insured versus uninsured banks. In particular, the Kansas deposit system was characterized by its voluntary membership and a set of regulations aimed at deterring adverse selection and moral hazard. This paper tests and finds evidence of omitted unobserved bank effects in Wheelock and Kumbakhar s (1995) moral hazard test. As a result, Wheelock and Kumbakhar (1995) (i) failed to find the significant negative effect that bank insurance membership had on bank surplus/loans ratio and (ii) overestimated the effect that bank insurance membership had on bank capital/assets ratio. That is, once the test for moral hazard includes bank heterogeneity, it renders more evidence that the Kansas insurance system suffered from moral hazard. 8

11 References: Calomiris, Charles W. (1989), Deposit Insurance: Lessons from the Record. Economic Perspectives, Federal Reserve Bank of Chicago, May/June, 13, Cecchetti, Stephen G. (1996), The Frequency of Price Adjustment, A Study of the Newsstand Prices of Magazines, Journal of Econometrics, 31, Chamberlain, Gary (1980), Analysis of Covariance with Qualitative Data, Review of Economic Studies, XLVII, Green, William H. (2000), Econometric Analysis, fourth ed., Prentice Hall. Green, William H. (1992), NLOGIT Version , Econometric Software, Inc. Grossman, Richard S. (1992), Deposit Insurance, Regulation, and Moral Hazard in the Thrift Industry: Evidence from the 1930s, The American Economic Review, 82, September, Heckman, James (1979), Sample Selection Bias as a Specification Error, Econometrica, January, 47,

12 Hsiao, C. (2003), Analysis of Panel Data, second ed., Cambridge: Cambridge University Press. Wheelock, David C., and Subal C. Kumbhakar (1995), Which Banks Choose Deposit Insurance? Evidence of Adverse Selection and Moral Hazard in a Voluntary Insurance System, Journal of Money, Credit, and Banking, Vol. 27, No. 1, February, Wheelock, David C., and Wilson, Paul W (1995), Explaining Bank Failures: Deposit Insurance, Regulation, and Efficiency. The Review of Economics and Statistics,

13 Table 1. Definition of Variables. Variable Definition DI Deposit Insurance Status: 1, insured bank; 0, otherwise. Age The number of years between a bank s charter date and balance sheet date. Bankpop The number of state chartered banks in a county divided by county population. DIratio The ratio of insured to total state banks in a county. Impacre The percentage change in county improved farm acreage, 1910 to Landvalue The percentage in county farm land value per acre, 1910 to Pop The percentage change in county population, 1910 to Rural The proportion of a county population located on farms or towns less than 2,500 persons. The following financial ratios are used as proxies for banks risk taking behavior: capital/assets, surplus/loans, cash/deposits, and loans/assets. 11

14 Table 2. Probit Model: Dependent Variable, DI. W&K Probit 1 Probit Random Effects Probit Variable Parameter Derivative Parameter Derivative Parameter Derivative Age ** ** ** (1.96) (2.16) (2.16) (2.23) (2.23) DIratio *** *** *** (12.39) (12.11) (12.12) (6.67) (6.74) Bankpop (0.16) (0.68) (0.68) (0.23) (0.23) Constant *** *** *** (4.95) (7.92) (7.87) (4.89) (4.87) ρ (47.97) Log L % Correct N = 816 DI = 0 for 389 obs DI = 1 for 427 obs LR test: Χ 2 1 = ; p value = Hausman test: h = ; p value = Estimates as reported in W&K, equation (1). t statistics are reported in cursive; statistical significance: ***, 1%; **, 5%; *, 10%. 12

15 Table 3. Moral Hazard Test: Stage 2. Dependent Variables: capital/assets, surplus/loan, cash/deposits, loans/assets. a capital/assets surplus/loans cash/deposits loans/assets Variable W&K OLS b,c OLS c FEM W&K OLS b,c OLS c FEM W&K OLS b,c OLS c FEM W&K OLS b,c OLS c FEM DI *** *** ** *** Age *** *** Bankpop * * ** *** *** *** *** *** *** Rural *** ** ** Pop *** Impacre *** *** Landvalue ** Constant *** *** *** *** *** *** *** *** R Adj R d. f s.d.e(i) OLS vs FEM OLS vs FEM OLS vs FEM OLS vs FEM F test F (203,606) = 5.73, p value =.0000 F (203,606) = 6.35, p value =.0000 F (203,606) = 2.97, p value =.0000 F (203,606) = 2.97, p value =.0000 LR test Χ = ; p value =.0000 Χ = ; p value =.0000 Χ = ; p value =.0000 Χ = ; p value =.0000 a b c Reported coefficients are 100 times larger than their actual value; t statistics are reported in cursive; statistical significance: ***, 1%; **, 5%; *, 10%. W&K OLS are the estimates reported in table 4 in W&K, where DI was estimated using a probit model. Standard errors were corrected for heteroscedasticity. 1