## 3 Results
### Linear Correlations Among the Yield, All Bands, and VIs in the Three Main Growth Stages  
#### 3.2.1 Linear Correlations Between Yield and All Bands  
The results of linear correlations at MT are shown in Table 5, with the mean \(R\). Regarding the yield correlation, mean values of \(R\) varied between 0.26 and 0.44 in B06, B07, B08, B08A, B11, and B12 and for B02, B03, B04, and B05, between \(-\)0.36 and \(-\)0.31. When locations and years were compared, the coefficients of correlation were variable, ranging from 0.25 to \(-\)0.62 in B04 and from 0.23 to 0.70 in B08, and this variability was similar in the other spectral bands (Table S1). Correlations with the yield were mainly negative in B02, B03, B04, and B05 across locations and years, while correlations were mostly positive  
Figure 5: Pixel yield anomaly by year and location ((**A**): location 1, (**B**): location 2) compared to the field area. The yield anomaly per pixel is the difference between each yield value acquired by the combine in a 10 m pixel and the average yield in each field where each pixel is located. in B06, B07, B08, BSA, B11, and B12. There were notable exceptions in some locations and years; the most remarkable was location 2 in year 3, when the correlations in the visible bands were not negative. However, this inconsistency between years was observed in both locations, i.e., year 2 in location 1 showed very low correlations, similar to those of years 3 and 4 in location 2. The collinearity study was useful to determine high correlations between some spectral bands. These results were, in this case, consistent for the mean values and each individual location and year, showing a clear pattern. The bands with a negative yield correlation (B02, B03, B04, and B05) were closely correlated with each other, reaching R-values of 0.91 on average (Table 5) and 0.74 when all locations and years were considered (Table S1). Spectral bands positively correlated with the yield (B08, B06, B07, B8A, B11, and B12) were closely correlated with each other with values close to 1 in the Red edge and NIR spectral bands (B08, B06, B07, and B8A) and values around 0.80 and 0.90 in the SWIR spectral bands (B11 and B12). Finally, weak correlations were found between the group of negative correlations with yield and the group of positive correlations with yield. The results of linear correlations at PI are shown in Table 6 with the mean \(R\) for all locations and years. The correlations between yield and spectral bands were lower (\(-\)0.16 to \(-\)0.07) in the group of negative correlations (B02, B03, B04, and B05) but higher (0.28 to 0.58) in the other bands. Differences were observed between the SWIR bands (B11 and B12) and the rest of the spectral bands, with the lowest \(R\) values (0.28 and 0.41). Conversely, with B07, B08, and BSA, \(R\) = 0.58 values were obtained in three spectral bands. Differences in \(R\) values between years were found in both locations similarly, being remarkable location 2 in year 3, when the correlations were positive and significant in all bands (Table S2), following a different pattern to the other years and to the previous growth stage. The results in the collinearity study were similar to MT, but the new correlation performance between the yield and bands was also found in the band-to-band collinearity. Thus, the coefficients of correlation among the B02, B03, B04, and B05 group were significant but lower than at MT; the correlations among B08, B07, and B8A approached 1, while with B06, they were lower but still of high value; and, finally, the collinearity between the SWIR bands and the other spectral regions started to decrease.