Let us consider that we want to study the production funtion a particular sector. 
To that end, we dispose information of 100 companys of:
- production
- number of skilled workers (l1t)
- number of non-skilled workers (l2t)
- labor productivity (wages/worked hours)
- heavy machinery capital (k1t)
- light machinery capital (k2t)
- capacity utilization rate (ucp)

Use this information to estimate the most adequate production function.