Comparisons in productivity analyzes should be made under similar conditions, whether they be the same years, ages or harvest times, the same agro-ecological zones or environments.
In order to make decisions about technology adoption, the sugarcane agribusiness permanently conducts comparative analyzes of different technologies to verify with commercial information data if they improve productivity and profitability.
In these comparisons, it is essential to start from the same or similar cultivation conditions so that the statistical or descriptive methods used provide reliable results.
Sugarcane production is largely based on the longevity of the plantation and its ability to sustain sugarcane production through cuttings, so a new variety must maintain TCH and yield, as minimum, on the level of the commercial variety grown before.
According to Carlos Viveros, breeder of the Cenicaña Variety Program, the mills and growers analyze the soquera capacity of the new varietal options to make planting decisions. The most recent example occurred with the CC 93-4418 variety, whose ability to sustain sugarcane production over time was questioned.
In this regard, Carlos Moreno, biometrist of the Economic and Statistical Analysis Service of the Research Center, explains that when it comes to comparing the behavior of two or more varieties with the commercial variety that serves as a control, through the cuts, the comparisons They must be as equitable as possible in order to guarantee the reliability of the results.
"The workforce productivity of the same variety cannot be comparable in a year with Niño conditions and in a year with Niña conditions, nor is it possible to do so with different harvest ages," he adds.
Having a level playing field to make comparisons is difficult; however, to consider the differential factors there are descriptive and statistical approaches that solve the problem to some extent.
An alternative is the analysis with a descriptive approach that, in the case of knowing the soquera capacity of the varieties, estimates trends or averages from the observation of the productions under certain conditions that must be similar, either the same years, ages or harvest times, the same agro-ecological zones or environments, not by global averages.
The other option of analysis is from general linear models of mixed effects that estimate the means by least squares for each of the levels of the factors considered (for example, varieties and cuts) and make comparisons between varieties by cut, they correct for harvest ages and eliminate the effect of the year factor (environment).
This type of analysis handles the 'standard error of estimation', which allows determining the reliability of the estimated population average.
With the use of this type of approach, Cenicaña continues to gain knowledge and experience to advance in the development of reliable technologies to improve the competitiveness of the Colombian sugarcane agroindustry.
In Library Catalog: Book: SAS for mixed models.
In Memories Forum 8, June 2016 Presentation: Commercial behavior of CC 93-4418 through the cuts.