Question

2.1 mammal life - spans. data was collected on life - spans (in years) and gestation lengths (in days) for 62 mammals. a scatterplot of life - span versus length of gestation is shown below.
(a) what type of an association is apparent between life - span and length of gestation?
(b) what type of an association would you expect to see if the axes of the plot were reversed, i.e., if we plotted length of gestation versus life - span?
(c) are life - span and length of gestation independent? explain your reasoning.
2.1 (a) positive association: mammals with longer gestation periods tend to live longer as well. (b) as - sociation would still be positive. (c) no, they are not independent. so part (a).

Explanation:

(a) By observing the scatter - plot, as the life span (in years) increases, the gestation length (in days) also seems to increase in general, indicating a positive association.
(b) If the axes were reversed, the pattern would still show a positive association. The positive relationship between the two variables is a characteristic of the data and not dependent on which variable is on which axis.
(c) The positive association implies that longer gestation periods are related to longer life spans. This could be due to biological factors such as more complex development during a longer gestation leading to a longer - lived organism.

Answer:

(a) There is a positive association between life span and length of gestation.
(b) The association would still be positive if the axes were reversed.
(c) Longer gestation periods are associated with longer life spans likely due to more complex biological development during longer gestations.