Print 3.6.4 Test (TS): Bivariate Data
Test

Probability and Statistics (S2863912)
Michael Donaldson
Points possible: 50
Date: _2/1/16___________

Answer the following questions using what you've learned from this unit. Write your answers in the space provided. Be sure to show all work.
SCATTERPLOTS

1. Maria is a veterinarian. She wants to know if the weight of a puppy depends on its length. To find out, Maria randomly selected 10 puppies that were two months old. She recorded the length and weight of each puppy in the table below.
Length
(inches) 40 7 33 24 14 48 9 18 13 21
Weight
(pounds) 7.2 1.3 9 5.8 2.5 9.7 2.3 1.6 1.8 2.9
Part A. Use the table to answer these questions. (1.5 points)
Why would these data be described as bivariate? The data are bivariate because they comprise sets for two different variables.

What is the explanatory variable (independent variable, x)? Length is the explanantory variable

What is the response variable (dependent variable, y)? Weigth is the response variables

Part B. Use your responses in Part A to write the puppy data as 10 ordered pairs (x, y). (2.5 points) (40,7.2),(7,1.3),(33,9),(24,5.8),(14,2.5),(48,9.7),(9,2.3),(18,1.6),(13,1.8),(21,2.9)

Part C. Use your ordered pairs from Part B to display the puppy data on the scatterplot below. (5 points)Student receives 0.5 point correctly plotting each ordered pair,for a maximum of 5 points.

Part D. Use the scatterplot from Part C to answer these questions. (2 points)
What kind of correlation exists between the length and weight of the puppies? Explain.
There is a positive correlation exists between the variables, because as the explanatory variable (Length) increases, the response variable (Weigth) increases.

Does this correlation imply causation? Explain.
It seems to imply causation, since it is logical that the