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Pesticide (1000 IRR/ha) 12,354.9 13,206.7 9,189.2 6,965.3

Fertilizer (1000 IRR/ha) 8,739.9 2,862.1 7,757.1 1,464.7
Average land use (ha) 2.3 1.9 3.1 2.2

Figure 1. Q-Q Boxplot of Efficiency Scores.

GAMS software was used to formulate super-efficiency DEA. The obtained

results present the efficiency score of both groups. A maximum score of efficiency
in the cooperative group is 1.48 whereas in the non-cooperative group the score

is 1.10. Expectedly, the mean of efficiency score for cooperative farms is more
than that of non-cooperative farms.

After the super-efficiency DEA was calculated, the statistical analysis was
conducted. the average of efficiency scores is compared statistically for both

groups. In order to compare the mean of two groups, in the statistical program R,
we first evaluate the normality of the data by Q–Q-plot and box plot as shown in

Figure 1. The upper diagrams (Q–Q plot) are the efficiency scores from the data,
while the left diagrams (box plot) are the statistic of the mean, median, min, max,

and standard deviation (SD). The upper diagrams serve for the non-cooperative

farms while the lower diagrams serve for the cooperative farms.
From the parametric view, the efficiency scores for non-cooperative farms
are quite similar to the normal distribution, unlike those of the cooperative farms.

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