Measuring heterogeneous preferences for cattle traits among cattle-keeping households in East Africa.

Derived S.D. Bulls Traits Coefficient Random Parameters in Utility Function Trypanosomosis 0.6684 *** (0.0812) Purchase price (U.S. $) 0.2229 * (0.3073) Traction potential 1.0789 *** (0.1243) Fertility 0.4235 *** (0.1344) Live-weight in kg 0.3301 *** (0.0523) Nonrandom Parameters in Utility Function Low watering frequency Coat color Constant Log likelihood at start values Simulated log likelihood at convergence N = 2,783 Likelihood ratio test 941.8 ([[chi square].sub.0.99] (20) = 37.6); McFadden [R.sup.2] = 0.312; Halton draws = 100 Hausman test statistic (restricted alternative 2) = 6.010, p-value = 0.111 Cows Traits Random Parameters in Utility Function Trypanosomosis 0.8006 *** (0.0934) Purchase price (U.S. $) 0.1161 *** (0.0279) Supplementary feeds 0.5031 *** (0.0954) Milk yield 0.2945 *** (0.0693) Reproduction ability 0.2173 * (0.1256) Nonrandom Parameters in Utility Function Low watering frequency Coat color Live-weight in kg Constant Log likelihood at start values Simulated log likelihood at convergence N = 3,036 Likelihood ratio test 793.6 ([[chi square].sub.0.99] (20) = 37.6); McFadden [R.sup.2] = 0.222; Halton draws = 100 Hausman test statistic (restricted alternative 2) = 8.332, p-value = 0.039 Notes: Standard errors are in parentheses. Single (*), double (**) and triple (***) denote significant variables at 10%, 5%, and 1% levels, respectively. Hausman's test procedure shows nonviolations of independence of irrelevant alternatives (IIA) with the mixed logit model for both bulls and cows at the 5% level. Table 5. Implicit Price Estimates of Cattle Traits in U.S. Dollar from Mixed Logit Models

E([[beta].sub.k]/ Trait [[beta].sub.p]) S. D. Good traction potential (bulls) 58.4 47.4 Trypanotolerance 24.7 16.7 High fertility (bulls) 22.6 17.1 Live-weight (per 10 kg) 10.5 6.2 Reproduction potential (cows) 9.4 6.9 Milk production (cows) 8.1 5.5 Watering frequency (bulls) 6.8 0.8 Purchased feed -10.7 9.7

supplements (cows) Table 6. Maximum Likelihood Estimates of Bull Traits from Latent Class Model

Class 1 Class 2 Class 3 Utility Function

Coefficients Trypanosomosis 0.2101 *** 0.2605 *** 1.1483 ***

(0.0743) (0.0476) (0.0687) Purchase price -0.1089 0.0964 * 0.0952 **

(0.1116) (0.0422) (0.0434) Watering frequency 0.1456 ** 0.1785 *** 0.0992

(0.0746) (0.0471) (0.0684) Coat color -0.0399 0.0523 -0.0143

(0.0642) (0.0423) (0.0555) Live(kg) 0.1040 0.2682 *** 0.1241 **

(0.0692) (0.0386) (0.0498) Traction 1.6664 *** 0.0851 ** 0.5099 ***

(0.0823) (0.0380) (0.0626) Fertility 0.2322 *** 0.7916 *** 0.0099

(0.0645) (0.0366) (0.0572) Constant -2.6555 *** -1.8350 *** -1.1524 ***

(0.3512) (0.2318) (0.2498) Class Membership

Coefficients Constant -1.2965 4.0756 ***

(1.2525) (1.4888) Educyrs -0.0028 -0.1307*

-0.0500 -(0.0788) Hhage 0.0149 -0.0424*

(0.0165) (0.0236) Agropast 3.2523 *** -3.4592 ***

(0.9236) (0.9821) Cropliv 0.8570 -2.2791 ***

(0.9260) (0.7600) Hhinc (U.S. $100) -0.0433 0.0437 ***

(0.0304) (0.0171) Number of observations 1,474 770 528 Latent class probability 0.5394 *** 0.2719 *** 0.1886 ***

(0.0332) (0.0310) (0.0276) Log likelihood -1204.281 Number of groups 253 Likelihood ratio test = 995.4

([[chi square].sub.0.99] (24) = 42.9) Notes: Standard errors are in parentheses. Single (*), double (**), and triple (***) denote significant variables at 10%, 5%, and 1% levels respectively. Table 7. Maximum Likelihood Estimates of Cow Traits from Latent Class Model

Class 1 Class 2 Class 3 Utility function

coefficients Trypanosomosis 2.1989 *** 0.9798 *** 0.3410 ***

(0.1706) (0.0912) (0.0317) Purchase price -0.0756 *** 0.0123 0.0412 ***

(0.0293) (0.0090) (0.0067) Milk yield 0.1944 0.2380 *** 0.4125 ***

(0.1233) (0.0736) (0.0298) Reproduction ability 0.4960 *** 0.0732 0.4864 ***

-(0.1481) -(0.0833) -(0.0266) Feeding requirement 0.1505 -1.3381 *** -0.3019 ***

(0.1699) (0.0976) (0.0343) Watering frequency -0.5464 ** 0.1368 0.1372 ***

(0.2570) (0.1046) (0.0444) Coat color -0.1121 0.0377 -0.0424

(0.1474) (0.0719) (0.0364) Live (kg) 0.1984 0.3574 * 0.3718 ***

(0.2264) (0.2021) (0.0721) Constant -5.1054 *** 0.8428 -2.4925 ***

(0.9945) (0.5398) (0.3028) Class Membership

Coefficients Constant -0.0038 -0.9184 **

(0.3216) (0.4545) Agropast 1.2205 *** -1.9657 **

(0.3216) (1.0184) Pastoral -2.1813 *** -0.5922

(0.6669) (0.5562) Hhinc (US. $100) -0.0341 ** -0.0491 *

(0.0155) (0.0274) Tsecont -0.0609 0.9857 **

(0.3468) (0.4890) N 1,248 408 1,368 Latent class probability 0.3998 *** 0.0900 *** 0.5101 ***

(0.0318) (0.0186) (0.0328) Log likelihood -1,362.695 Number of groups 253 Likelihood ratio test = 675.1 ([[chi square].sup.2.sub.0.99] (28) = 48.3) Notes: Standard errors are in parentheses. Single (*), double (**), and triple (***) denote significant variables at 10%, 5%, and 1% levels, respectively. Table 8. Class-Specific Implicit Prices of Cattle Traits (U.S. Dollar) Trait Class 1 Class 2 Bulls Trypanotolerance 22.7 (15.1) (a) 29.6 (7.6) Good traction 159.1 (27.7) 11.1 (6.9) High fertility 23.4 (12.1) 81.4 (5.5) Live-weight (per 10 kg) NS 27.9 (1.3) Watering frequency 14.3 (4.5) 18.7 (1.1) Cows Purchased feed supplements NS -102.8 (11.8) High milk yield NS 20.2 (17.2) High reproduction potential 6.8 (0.8) NS Trait Class 3 Bulls Trypanotolerance 115.9 (7.6) Good traction 54.5 (6.4) High fertility NS (b) Live-weight (per 10 kg) 13.5 (1.0) Watering frequency NS Cows Purchased feed supplements -8.4 (4.2) High milk yield 11.1 (7.8) High reproduction potential 13.3 (11.4) (a) Standard deviations in parenthesis. (b) NS: trait not statistically significant.