Do these data indicate that miRNA diversity and animal complexity are negatively correlated, positively correlated, or uncorrelated? Explain

In the study, scientists used two variables: the number of miRNAs and an average number of cell types to determine the relationship between miRNA diversity and animal complexity.

To establish the relationship between the two variables, researchers calculated the correlation coefficient.

The correlation coefficient reflects the magnitude and direction of a linear relationship between two variables. The correlation coefficient is calculated using the following formula:

$r=\frac{\frac{1}{n-1}\sum (x_i-\overline{x)}(y_i-\overline{y})}{s_x{s}_y}$

where x and y are the two variables, and n is the number of observations.

r ranges from -1 to 1. The value of rmore than 1 indicates a positive relationship, whereas r less than 1 indicates a negative relationship between the two variables.

The r calculated using the data from the study is 0.957. Since the value of r is greater than zero, the value indicates that miRNA diversity and animal complexity are positively correlated.