Table 6. Open in new tab Marginal effect...

	Model (1) main model	Model (2) Separate prod. functions, no endogeneity	Model (3) Joint prod. function
Work and machinery	−1.32	5.71**	−0.02	4.05	4.99**
Fertilizers	−7.93	−7.85	−0.28	−0.99	1.65
Mechanical pest control	−0.003	−0.009	−0.003	−0.008	−0.005**
Herbicide	0.58*	−8.32**	0.45	0.72	0.11
Fungicide	−0.99*		0.95		3.31***

	Model (1) main model	Model (2) Separate prod. functions, no endogeneity	Model (3) Joint prod. function
Work and machinery	−1.32	5.71**	−0.02	4.05	4.99**
Fertilizers	−7.93	−7.85	−0.28	−0.99	1.65
Mechanical pest control	−0.003	−0.009	−0.003	−0.008	−0.005**
Herbicide	0.58*	−8.32**	0.45	0.72	0.11
Fungicide	−0.99*		0.95		3.31***

Table 6.

Marginal effect at the mean (MEM) of inputs on yields.

	Model (1) main model		Model (2) Separate prod. functions, no endogeneity		Model (3) Joint prod. function
MEM on yields	Conventional	Low-input	Conventional	Low-input	All
Work and machinery	−1.32	5.71**	−0.02	4.05	4.99**
Fertilizers	−7.93	−7.85	−0.28	−0.99	1.65
Mechanical pest control	−0.003	−0.009	−0.003	−0.008	−0.005**
Herbicide	0.58*	−8.32**	0.45	0.72	0.11
Fungicide	−0.99*		0.95		3.31***

	Model (1) main model		Model (2) Separate prod. functions, no endogeneity		Model (3) Joint prod. function
MEM on yields	Conventional	Low-input	Conventional	Low-input	All
Work and machinery	−1.32	5.71**	−0.02	4.05	4.99**
Fertilizers	−7.93	−7.85	−0.28	−0.99	1.65
Mechanical pest control	−0.003	−0.009	−0.003	−0.008	−0.005**
Herbicide	0.58*	−8.32**	0.45	0.72	0.11
Fungicide	−0.99*		0.95		3.31***

Note: *P < 0.1, **P < 0.05, ***P < 0.01.

Given the non-linear functional form of our production function, we cannot compute the marginal effect of inputs on yields. We need to consider the marginal effect at the mean, that is, we consider the effect on yields when increasing the quantity of a particular input when other variables equal the sample average. As such, coefficients’ direct interpretation is difficult as they heavily depend on other variables values.

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