Biology – Biodiversity | e-Consult

(a) Spearman’s rank correlation coefficient measures the strength and direction of the monotonic relationship between two ranked variables. It assesses whether as one variable increases, the other tends to increase or decrease, without assuming a linear relationship.

(b) The value of 0.78 indicates a strong positive monotonic relationship between the amount of sunlight and plant growth rate. This means that as the amount of sunlight increases, the plant growth rate tends to increase. The strength of 0.78 suggests a fairly reliable association. However, it's important to remember that correlation does not equal causation. Other factors could influence plant growth.

(c) Spearman’s rank correlation is more appropriate than Pearson’s when the data is not normally distributed or contains outliers. Plant growth data might not be normally distributed, especially if there are significant variations in other factors affecting growth.