Table 1. Difference in practices between certified and noncertified farms: continuous variables (n = 86).

Certified Noncertified Wilcoxon test p - value
Median values
Biophysical characteristics
Altitude
 
1648
 
1645
 
484
 
0.689
 
Socioeconomic characteristics
Age of household’s head 53 55 505.5 0.503
Number of people in the household 4 4 267.5 0.203
Number of years of education of the head of household 5 5 240.5 0.891
Highest number of years of education of household members
 
13
 
11
 
394.5
 
0.042*
 
Ecosystem conservation
Number of tree species per hectare
 
9
 
6
 
626.5
 
0.000*
 
Land expansion
Number of hectares of land devoted to coffee 4.5 4 603.5 0.003*
Number of hectares expanded since certification/last 5 years 1 1 403.5 0.271
* Significant at the 0.05 level.