8/14/2019 An Index of Management for Potato Farms in Wonosobo,
Central Java
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4Table 1 Estimated coefficients and related statistics without
and with management index (Koefisien persamaan regresi
tanpa dan dengan pencantuman indeks pengelolaan)
Independent variable
(Peubah tak bebas)
Without management index With management index
Coefficient Coefficient
Constant (Konstanta) 2.956002 4.924805
Land
(Lahan)
0.052316
(0.170000)
0.338800 *
(0.185701)
Seed
(Bibit)
0.499903 ***
(0.175740)
0.327477 *
(0.084434)
Manure
(Ppk. Kandang)
- 0.075478
(0.092557)
- 0.089700
(0.084434)
Fertilizer
(Ppk. Buatan)
0.364506 ***
(0.159972)
0.379804 **
(0.145770)
Pesticide
(Pestisida)
0.107353
(0.118897)
0.048230 ***
(0.010315)
Labor
(Tenaga Kerja)
0.096046
(0.203077)
0.103622
(0.187855)
Management
(Pengelolaan)
- 0.344074 ***
(0.123200)
Returns to scale 1.044646 1.197933
R2
0.911160 0.928570F Stat. 56.411940 *** 59.430750 ***
Figures in brackets are standard errors
*** Significant at the 1% level
** Significant at the 5% level
* Significant at the 10% level
CONCLUSIONS
An index of educational level and years of experience seems to
be usable as a proxy formanagerial ability of potato farmers in
Wonosobo. Further education and experience will be likely to
increase potato yield. Farmers with longer experience and better
education are more productive. Theinclusion of management index
provides a better statistical adequacy of the fitted production
function.This is reflected by the improvements in the magnitude of
determination coefficient (R 2) and the
significance of the independent variables.
REFERENCES
Debertin, D. L. (1986). Agricultural Production Economics.
Macmillan Publishing Company, New York.
Doll, J. P. (1974). On Exact Multicollinearity and the Estimates
of the Cobb-Douglas Production
Function. American Journal of Agricultural Economics, 56,
556-563.
