Exploration & description/Importance of cattle

The bar chart for average numbers of different species kept by homesteads (for those homesteads that kept that species) showed that the numbers of cattle kept were as many as those of chickens. This seems a little surprising but, at the same time, indicates the overall importance of cattle to the homestead. 

The bar chart also indicated that the homesteads, for which livestock provided the primary source of income, tended to have slightly higher average numbers of cattle, sheep, chickens and pigs than those where livestock did not provide the primary source of income.

However, although to be expected, it is possible that the differences may not be statistically significant, but influenced (as we have already seen) by a few homesteads with large numbers of the species concerned. We therefore need to compare distributions after transformation of the data by a natural logarithm transformation stored in variable log_cat_no.