The Specification of the Money Demand Function

The monetary model developed in this section is quite new in the sense that it yields a specific estimable form for asset demand functions as in equations 9a and 9b, which are used to derive the welfare cost function in a currency– deposit framework for both the consumer surplus and the compensating variation approaches. In addition, the currency– deposit model is more general than the earlier monetary models because, as discussed in the previous section, it nests the currency-only and deposits-only models. As presented above, standard utility functions yield double-log demands for money although the semi-log form has been widely used in money demand studies, more a matter of convenience than theoretical or empirical attractiveness. The convenience comes from its simplicity, the fact that steady-state seigniorage is easily defined at a constant nominal interest rate and the fact that the seigniorage-maximizing interest rate as well as the maximum seigniorage are easily derived. However, the semi-logarithmic form has its drawbacks. The micro-foundation of the semi-log specification in either “the shopping time” or “the money-in-the-utility function” approach is somewhat ad hoc. We have to impose a specific form on the utility function or on the shopping time technology in order to arrive at the constant semi-elasticity Cagan-type demand for money. The utility function and the similarly shaped shopping time technology take the following unusual forms, respectively: u~c t ,m t ,d t 5 m t ~1 1 w 2 ln m t a 1 d t ~1 1 v 2 ln d t b 1 v~c t , u m . 0,u d . 0,u c . 0 c~c t ,m t ,d t 5 m t ~ln m t 2 w 2 1 t a 1 d t ~ln d t 2 v 2 1 t b 1 v~c t , c m , 0,c d , 0,c c . 0 which imply the following Cagan-type demand for currency and deposits: ln m t 5 w 2 av c i t , ln d t 5 v 2 bv c ~i t 2 i d ~t, where the marginal utility of consumption is assumed to be a positive constant, v c . 0.

III. The Specification of the Money Demand Function

This section concentrates on the econometric approach we use to identify the proper specification of U.S. money demand. A search for an improved specification of the long-run demand for money leads us to consider econometric issues in the treatment of short-run dynamics. The calculation of the parameters of long-run relationships from estimated models, and the forms of particular models, such as partial adjustment and error correction models, are also discussed in this section. To determine what form the U.S. money demand will take, the Box–Cox transforma- tion, g ~l ~i t 5 i t l 2 1 l , 10 Welfare Cost of Inflation 239 is applied to the i t variable. Note that in the following regression equation, which assumes a unitary quantity elasticity of money demand, ln~m t q t d 5 b 1 b 1 S i t l 2 1 l D 1 e t , 11 when l equals one, equation 11 reduces to ln~m t q t d 5 ~ b 2 b 1 1 b 1 i t 1 e t , 12 and the demand for real money balances becomes semi-logarithmic in i t . When l equals zero, the transformation is, by L’Hopital’s rule, lim l30 S i t l 2 1 l D 5 ln i t Hence, l 5 0 in g l i t implies that the demand for real balances is logarithmic in i t , ln~m t q t d 5 b 1 b 1 ln i t 1 e t . 13 In estimating the regression equation of the demand for real balances, the crucial step is to define the specific form of money demand and to find an efficient mechanism to estimate short-run money demand equations, which are consistent with imposed long-run relationships. The partial adjustment and error correction models have been widely used as short-run dynamic specification to estimate long-run parameters of money demand. In this paper, dynamics are first allowed for by means of real partial adjustment model along the lines of Hwang 1985, who rationalizes partial stock adjustment as an optimization between costs of adjustment of money balances and costs of being out of equilibrium: 3 ln m t 2 ln m t21 5 f~ln m t d 2 ln m t21 . 14 Substituting equation 12 into equation 14 yields ln ~m t q t d 5 ~ fb 1 ~fb 1 S i t l 2 1 l D 1 ~1 2 fln ~m t21 q t21 1 « t . 15 As an alternative to the partial adjustment model, a general distributed lag model and its transformation to error correction have been increasingly used for estimation of money demand. Following Baba et al. 1992 and Banerjee at al. 1993 among many others, 4 we apply the error correction mechanism to U.S. money demand. To illustrate the derivation 3 Partial adjustment is typically motivated by cost-minimizing behavior wherein the costs of disequilibrium are balanced against adjustment costs. Following Hwang 1985, consider a quadratic cost function of the form: C 5 Ã 1 ln M t d 2 ln M t ] 2 1 Ã 2 [ln M t 2 ln M t21 2 zln P t 2 ln P t21 ] 2 where the first and second terms of the function correspond to the disequilibrium and adjustment costs, respectively. Minimizing costs with respect to M t yields: ln M t 2 ln M t21 5 fln M t d 2 ln M t21 1 z1 2 fln P t 2 ln P t21 where f 5 Ã 1 Ã 1 1 Ã 2 . Thus, when z 5 1, this expression reduces to the real partial adjustment model in which real balances are adjusted: ln m t 2 ln m t21 5 f ln m t d 2 ln m t21 . 4 For example, Hendry 1980 used this procedure for U.K. money demand and Rose 1985 estimated an error correction model for U.S. money demand. 240 T. G. Bali of this model from a distributed lag model, we consider a specification with only one lag of each variable as in ln ~mq t 5 a 1 a 1 i t 1 a 2 i t21 1 a 3 ln ~mq t21 1 e t 16 for the semi-log form with unitary quantity elasticity. Note that the long-run interest rate semi-elasticity in this model is a 1 1 a 2 1 2 a 3 . Now subtract ln mq t21 from both sides of equation 16 and then add and subtract a 1 i t21 on the right hand side to get Dln ~mq t 5 a 1 a 1 Di t 1 ~ a 1 1 a 2 i t21 1 ~ a 3 2 1ln ~mq t21 1 e t . 17 To estimate the error correction model, equation 17 can be rewritten as Dln ~mq t 5 a 1 a 1 Di t 1 ~ a 3 2 1ln ~mq t21 2 ki t21 1 e t , 18 where k 5 a 1 1 a 2 a 3 2 1. Equation 18 is called an error correction model because the term [ln mq t21 2 k i t21 ] represents last period’s error or deviation of money from its long-run relationship with interest rate. To determine whether the money demand function with the error correction mechanism is logarithmic or semi-logarithmic, the Box–Cox transformation is applied to i t and i t-1 in equation 16: ln ~mq t 5 a 1 a 1 S i t l 1 2 1 l 1 D 1 a 2 S i t21 l 2 2 1 l 2 D 1 a 3 ln ~mq t21 1 e t . 19 Note that when l 1 5 l 2 5 0, equation 19 reduces to the error correction model with double-log function Dln ~mq t 5 a 1 a 1 Dln i t 1 ~ a 3 2 1ln ~mq t21 2 kln i t21 1 e t . 20 When l 1 5 l 2 5 1, the demand for real balances takes the semi-logarithmic form given in equation 18. Having provided the framework we utilize to identify the true form of U.S. money demand, we now describe the data, and then present the money demand estimates and econometric test results. After all variables used in our analysis are seasonally adjusted by the standard U.S. Bureau of Census methods of seasonal adjustment, the demand for real balances is estimated with four different monetary aggregates currency, demand deposits, monetary base, M1, using quarterly data for the period 1957:I–1997:II. 5 Furthermore, to test whether the empirical results depend on the choice of a scale variable, two different quantity variables consumption, income are utilized in money demand estimates. We use the GDP deflator when real GDP and the consumer price index CPI when real consumption is employed as the scale variable. The 3-month T-bill rate is used as the opportunity cost of holding money in our estimation. The demand for real balances is estimated by means of OLS when the short-run partial adjustment specification takes either the semi-log form: ln mq t 5 b 1 b 1 i t 1 b 3 ln mq t21 , or the double-log form: ln mq t 5 b 1 b 1 ln i t 1 b 3 ln mq t21 . The OLS estimates and related statistics of the partial adjustment model are presented in Table 1. When dynamics are allowed for by means of autoregressive distributed lag model, OLS 5 Data source is International Monetary Fund International Financial Statistics on CD-ROM. Welfare Cost of Inflation 241 is applied both to the error correction model with the semi-log function: Dln mq t 5 a 1 a 1 Di t 1 a 1 1 a 2 i t21 1 a 3 2 1 ln mq t21 1 e t , and the model with the double-log function: Dln mq t 5 a 1 a 1 Dln i t 1 a 1 1 a 2 ln i t21 1a 3 21 ln mq t21 1 e t . Table 2 shows the short-run estimates and related statistics of the error correction model. The nonlinear money demand estimates with the partial adjustment and error correction models are demonstrated in Tables 3 and 4, respectively. 6 The long-run values of the 6 Although they are not presented in our tables, the statistical results from the augmented Dickey–Fuller 1979 test imply that all of the variables used in this study are characterized as nonstationary I1 variables because we find that there is a unit root in the level of the variables but there is none in their first differences. Because the variables are found to be nonstationary I1, we check for cointegration using Engle–Granger 1987 Table 1. Short-Run Money Demand Estimates MoneyScale Specification b 0,s b 1,s b 2,s R 2 Log- likelihood h statistic ARCH1 CurrencyGDP Semi-log 20.4554 24.0831 0.5852 3.6610 0.8415 22.034 0.8963 301.8255 21.3580 0.0418 CurrencyGDP Double-log 20.8338 25.5171 0.0515 5.1047 0.7793 19.084 0.9034 307.5597 21.5507 0.1479 CurrencyCONS Semi-log 20.3070 23.7611 0.4927 3.4532 0.8730 26.545 0.9100 307.8868 22.2179 0.1426 CurrencyCONS Double-log 20.5878 25.1993 0.0430 4.8286 0.8256 23.740 0.9157 313.1096 22.5618 0.4442 DepositsGDP Semi-log 20.0281 22.0103 1.2119 2.2296 0.9832 130.37 0.9914 365.1336 22.3997 1.0901 DepositsGDP Double-log 20.0812 22.9543 0.0091 2.1818 0.9841 131.88 0.9914 365.0295 22.4957 1.2193 DepositsCONS Semi-log 20.0142 21.4230 1.1982 2.3150 0.9880 147.67 0.9931 370.2916 23.8533 6.2435 DepositsCONS Double-log 20.0675 22.9161 0.0091 2.2785 0.9889 148.93 0.9931 370.2090 23.9499 6.5574 MBGDP Semi-log 20.0750 22.6830 0.2225 2.5222 0.9685 84.818 0.9877 376.4112 0.1634 0.0240 MBGDP Double-log 20.1700 23.6215 0.0184 3.2480 0.9582 77.349 0.9880 378.4363 20.0202 0.0446 MBCONS Semi-log 20.0429 22.3766 0.1955 2.6021 0.9773 109.56 0.9915 391.9322 21.0842 0.0249 MBCONS Double-log 20.1167 23.6370 0.0157 3.3492 0.9702 102.76 0.9917 394.0756 21.3411 0.0343 M1GDP Semi-log 20.0437 23.1077 0.2385 2.7749 0.9672 94.084 0.9903 383.2190 21.9808 0.0864 M1GDP Double-log 20.1272 23.9127 0.0186 3.3357 0.9582 84.700 0.9905 384.8668 22.1844 0.0985 M1CONS Semi-log 20.0209 22.5054 0.2068 2.7013 0.9760 115.16 0.9926 391.7311 23.7070 0.4429 M1CONS Double-log 20.0864 23.7658 0.0157 3.2363 0.9698 106.63 0.9927 393.2633 23.9471 0.6125 Note: This table presents the short run estimates of the demand for currency, deposits, monetary base MB, and M1 using quarterly data for the period 1957:I and 1997:II. The scale elasticity of money demand is assumed to be unity. b’s are the coefficients in the semi-log and double-log form of money demand with the partial adjustment model. t-ratios are shown in parentheses. indicate the cases in which the h statistics and ARCH1-statistics are significant at the 5 percent 1 percent level of significance. The short-run parameters are estimated from the following semi-log and double-log specification with the partial adjustment model: ln mq t 5 b 0,s 2 b 1,s i t 1 b 2,s ln mq t21 semi-log, ln mq t 5 b 0,s 2 b 1,s ln i t 1 b 2,s ln mq t21 double-log. 242 T. G. Bali parameters presented in Table 5 are unscrambled from the short-run estimates given in Tables 1 and 2. As pointed out earlier, this section attempts to identify the correct specification of the U.S. money demand function employing the nonlinear form of money demand with test. According to the cointegration test results, the U.S. time series are cointegrated of order 1,1. We test autocorrelation using the Durbin-h statistics. As presented in Tables 1 through 4, there is autocorrelation in some of the estimated money demand equations when consumption is used as the scale variable. Given the presence of a lagged endogenous variable, autocorrelation implies that OLS estimates are biased and inconsistent. We test for the presence of autoregressive conditional heteroscedasticity using ARCH-LM test. As shown in Tables 1 through 4, there are no ARCH errors in the estimated money demand equations except for the deposit demand scaled with consumption at the 1 percent level of significance. Table 2. Short-Run Money Demand Estimates Error Correction Model MoneyScale Specification a 0,s a 1,s a 2,s a 3,s Log- likelihood h statistics ARCH1 CurrencyGDP Semi-log 20.4041 23.5375 21.1772 23.2591 20.5003 23.0255 20.1403 23.5798 303.5142 21.2971 0.0307 CurrencyGDP Double-log 20.6512 24.1221 20.1084 25.2806 20.0395 23.7465 20.1732 24.0778 312.5122 21.5923 0.5645 CurrencyCONS Semi-log 20.2807 23.3488 20.9146 22.6234 20.4394 22.9715 20.1159 23.4240 308.7831 22.1852 0.1335 CurrencyCONS Double-log 20.4806 24.0428 20.0888 24.4334 20.0349 23.7392 20.1430 23.9344 316.3572 22.5021 1.0175 DepositsGDP Semi-log 20.0234 21.8366 28.2502 26.3031 20.5717 21.1280 20.0116 21.6765 380.8015 22.3568 2.4222 DepositsGDP Double-log 20.0478 21.9185 20.0814 26.9983 20.0044 21.1690 20.0105 21.5717 384.5181 22.5171 2.7280 DepositsCONS Semi-log 20.0131 21.4162 27.5303 25.8482 20.6577 21.3450 20.0082 21.3254 383.5258 23.7762 4.8271 DepositsCONS Double-log 20.0439 22.0256 20.0697 25.9836 20.0054 21.4503 20.0074 21.2092 384.3083 24.1104 5.6003 MBGDP Semi-log 20.0620 22.2218 20.7543 23.3594 20.1683 21.8860 20.0256 22.2323 379.7219 0.2155 0.0380 MBGDP Double-log 20.1114 22.4432 20.0741 25.8149 20.0113 22.0618 20.0279 22.3349 389.4991 20.0199 0.0398 MBCONS Semi-log 20.0381 22.0960 20.5352 22.6000 20.1657 22.1663 20.0198 22.1949 393.5241 21.2395 0.0335 MBCONS Double-log 20.0869 22.7340 20.0572 24.8292 20.0115 22.4697 20.0222 22.3930 401.1110 21.1174 0.0162 M1GDP Semi-log 20.0329 22.4563 21.1330 25.5141 20.1412 21.6966 20.0228 22.3033 393.9576 21.9777 0.0038 M1GDP Double-log 20.0792 22.5457 20.0782 26.5021 20.0106 21.9833 20.0270 22.5167 398.9437 22.2589 0.5797 M1CONS Semi-log 20.0174 22.1534 20.9156 24.5998 20.1405 21.8620 20.0178 22.1481 398.9261 23.9091 1.1371 M1CONS Double-log 20.0617 22.7285 20.0613 25.1930 20.0107 22.2455 20.0218 22.4533 401.8222 24.0113 1.7890 Note: This table presents the short run estimates of the demand for currency, deposits, monetary base MB, and M1 using quarterly data for the period 1957:I and 1997:II. The scale elasticity of money demand is assumed to be unity. a’s are the coefficients in the semi-log and double-log form of money demand with the error correction model. t-ratios are shown in parentheses. indicate the cases in which the h statistics and ARCH1-statistics are significant at the 5 percent 1 percent level of significance. The short-run parameters are estimated from the following semi-log and double-log specification with the error correction model: D ln m t 5 a 0,s 1 a 1,s D i t 1 a 2,s i t21 1 a 3,s ln m t21 semi-log, D ln m t 5 a 0,s 1 a 1,s D ln i t 1 a 2,s ln i t21 1 a 3,s ln m t21 double-log. Welfare Cost of Inflation 243 Table 3. Short-Run Nonlinear Money Demand Estimates Partial Adjustment Model MoneyScale b 0,s b 1,s b 2,s l R 2 Log- likelihood h statistic ARCH1 CurrencyGDP 20.7677 25.2915 0.0088 0.9849 0.7751 19.071 20.5829 21.9382 0.9056 309.4117 22.3583 0.7421 CurrencyCONS 20.5300 24.9265 0.0059 0.8753 0.8209 23.683 20.6563 21.9473 0.9177 315.0058 23.4274 1.5833 DepositsGDP 20.5289 20.2047 0.3826 0.1431 0.9834 129.23 0.7530 0.5173 0.9914 365.1401 22.4229 1.1326 DepositsCONS 20.5574 20.2012 0.4281 0.1460 0.9882 145.84 0.6762 0.5477 0.9931 370.2936 23.8840 6.4233 MBGDP 20.1437 23.3754 0.0017 0.5878 0.9558 76.391 20.7787 21.5660 0.9882 379.5291 20.4423 0.0001 MBCONS 20.0917 23.2126 0.0013 0.5634 0.9685 101.86 20.8253 21.5921 0.9919 395.2832 21.8117 0.0044 M1GDP 20.1040 23.1641 0.0042 0.5972 0.9567 83.493 20.4956 20.9638 0.9906 385.2848 22.3844 0.0029 M1CONS 20.0650 22.6745 0.0032 0.5334 0.9688 105.42 20.5318 20.9244 0.9927 393.6742 24.1407 1.2538 Note: This table presents the nonlinear short run estimates of the demand for currency, deposits, monetary base MB, and M1 using quarterly data for the period 1957:I and 1997:II. The scale elasticity of money demand is assumed to be unity. t-ratios are shown in parentheses. indicate the cases in which the h statistics and ARCH1-statistics are significant at the 5 percent 1 percent level of significance. The short-run parameters are estimated from the following nonlinear specification with the partial adjustment model: ln~mq t 5 b 0,s 2 b 1,s S i t l 2 1 l D 1 b 2,s ln~mq t21 Table 4. Short-Run Nonlinear Money Demand Estimates Error Correction Model MoneyScale a 0,s a 1,s l 1 a 2,s l 2 a 3,s Log- likelihood h statistics ARCH1 Currency GDP 20.6104 23.8665 20.0370 20.9956 20.3325 21.1879 0.0292 0.6182 20.2421 20.5306 20.1777 24.1458 313.7701 22.4021 1.1957 Currency CONS 20.4372 23.6162 20.0243 20.8228 20.4023 21.2034 0.0217 0.4883 20.2495 20.4343 20.1484 24.0562 317.9059 23.6135 2.3204 Deposits GDP 0.0020 0.0075 20.1671 20.8114 0.1443 0.5784 0.1889 0.7683 0.1800 0.6812 20.0102 21.4819 384.7783 22.7922 2.9198 Deposits CONS 0.1193 0.2198 20.3113 20.6937 0.3018 1.0110 0.4181 0.6381 0.3778 1.1560 20.0070 21.1113 385.1746 23.9878 5.3098 MBGDP 20.1100 22.3991 20.0220 21.0799 20.3651 21.4320 0.0140 0.8709 20.4513 21.4508 20.0284 22.3449 391.2972 20.9259 0.8309 MBCONS 20.0793 22.4431 20.0130 20.8773 20.4483 21.4525 0.0080 0.6598 20.5201 21.2835 20.0231 22.4616 402.9537 21.7889 0.7834 M1GDP 20.0669 20.9990 20.1156 21.3917 0.1205 0.5329 0.1154 1.2285 0.1676 0.6472 20.0272 22.4510 399.1715 22.3755 0.7103 M1CONS 20.0221 20.2704 20.1010 21.1247 0.1531 0.5407 0.1261 0.9601 0.2923 0.8520 20.0224 22.4632 402.2433 24.1885 1.8221 Note: This table presents the nonlinear short run estimates of the demand for currency, deposits, monetary base MB, and M1 using quarterly data for the period 1957:I and 1997:II. The scale elasticity of money demand is assumed to be unity. t-ratios are shown parentheses. indicate the cases in which the h statistics and ARCH1-statistics are significant at the 5 percent 1 percent level of significance. The short-run parameters are estimated from the following nonlinear specification with the error correction model: D lnm t 5 a 0,s 1 a 1,s S i t l t 2 1 l 1 D 1 a 2,s S i t21 l 2 2 1 l 2 D 1 a 3,s lnm t21 244 T. G. Bali Box–Cox restriction: a semi-logarithmic Cagan-type money demand function will be the proper specification if the value of l in equation 15 or if the values of l 1 and l 2 in equation 19 are found to be statistically not different from one whereas if l in the partial adjustment model or l 1 and l 2 in the error correction model are statistically equal to zero then the demand for real balances is logarithmic in i t . In other words, having computed the estimate of l or l 1 and l 2 , the next step is to test whether the true l or true l 1 and l 2 is are statistically different from one or different from zero. To serve the purpose, two different econometric tests—the Wald test and the Likelihood Ratio test—are applied to the nonlinear money demand equations presented in equations 15 and 19. As demon- strated in Tables 6 and 7, for each monetary aggregate and each scale variable, the semi-log form is rejected but the double-log form is not at the 5 percent level of Table 5. Long-Run Money Demand Estimates MoneyScale Specification Partial Adjustment Model Error Correction Model b b 1 a a 1 CURRENCYGDP Semi-log 22.8738 263.750 3.6930 5.3220 22.8799 257.203 3.5656 4.5975 CURRENCYGDP Double-log 23.7786 244.488 0.2335 8.1587 23.7598 235.934 0.2278 6.4644 CURRENCYCONS Semi-log 22.4167 244.056 3.8785 4.5741 22.4210 240.516 3.7904 4.1057 CURRENCYCONS Double-log 23.3707 231.810 0.2466 6.9084 23.3605 226.583 0.2438 5.7209 DEPOSITSGDP Semi-log 21.6788 26.1138 72.317 1.8196 22.0200 25.0461 49.268 1.0818 DEPOSITSGDP Double-log 25.1160 22.8566 0.5743 1.7077 24.5552 22.0930 0.4207 1.0577 DEPOSITSCONS Semi-log 21.1866 23.1346 99.852 1.5569 21.5880 22.9395 79.748 1.0522 DEPOSITSCONS Double-log 26.0607 21.9604 0.8161 1.4377 25.9193 21.4208 0.7279 1.0004 MBGDP Semi-log 22.3799 217.014 7.0645 3.0977 22.4255 214.267 6.5814 2.4314 MBGDP Double-log 24.0635 213.353 0.4388 4.3868 23.9913 29.5724 0.4055 2.9649 MBCONS Semi-log 21.8921 210.596 8.6147 2.7901 21.9239 29.5052 8.3780 2.4128 MBCONS Double-log 23.9166 29.2631 0.5277 3.8580 23.9129 27.1972 0.5164 2.9674 M1GDP Semi-log 21.3326 210.383 7.2649 3.5370 21.4471 27.7541 6.2057 2.2876 M1GDP Double-log 23.0405 210.642 0.4454 4.7679 22.9308 27.4081 0.3916 3.0054 M1CONS Semi-log 20.8704 25.2453 8.6020 3.0690 20.9750 24.3603 7.8865 2.2421 M1CONS Double-log 22.8662 27.1013 0.5205 4.0315 22.8325 25.3913 0.4911 2.9552 Note: This table presents the long-run parameter estimates of the demand for currency, deposits, monetary base MB, and M1 with the partial adjustment and error correction models. The long-run parameters are unscrambled from the short-run estimates: b 5 b 0,s 12b 2,s and b 1 5 b 1,s 12b 2,s are obtained from ln mq t 5 b 0,s 2 b 1,s i t 1 b 2,s ln mq t21 or ln mq t 5 b 0,s 2 b 1,s ln i t 1 b 2,s ln mq t21 a 5 2a 0,s a 3,s and a 1 5 2a 2,s a 3,s are obtained from D ln m t 5 a 0,s 1 a 1,s D i t 1 a 2,s i t21 1 a 3,s ln m t21 or Dln m t 5 a 0,s 1 a 1,s D ln i t 1 a 2,s ln i t21 1 a 3,s ln m t21 Welfare Cost of Inflation 245 significance, implying that the double-log function with constant elasticity of less than one is a more accurate characterization of the actual data.

IV. The Welfare Cost of Inflation