Oysters are categorized for retail as small, medium, or large based on their volume. The grading process is slow and expensive when done by hand. A computer program estimates oyster volume based on the pixel area of two-dimensional (2D) images of the oysters. Table 3.3 shows the actual volume (in cm) and 2D reconstruction (in thousands of pixels) for 30 oysters.

(a) We want to know whether the 2D imaging program is a good predictor oyster volume. Therefore, 2D reconstruction is in our explanatory variable here. Make a scatterplot of 2D reconstruction and actual volume.

(b) Describe the overall pattern of the relationship: its form, direction, and strength. If appropriate, give the correlation coefficient. Would you say that the 2D system is an accurate way to assess oyster volume?