Question

Location	Percent Obesity	Median Income
Alabama	33.5	49,936
Alaska	29.7	68,734
Arizona	28.9	62,283
Arkansas	35.9	49,781
California	24.7	70,489
Colorado	21.3	73,034
Connecticut	26.3	72,812
Delaware	30.7	65,012
District of Columbia	21.7	85,750
Florida	26.2	54,644
Georgia	30.5	55,821
Hawaii	22.1	80,108
Idaho	28.9	58,728
Illinois	29.3	70,145
Indiana	32.7	59,892
Iowa	30.9	68,718
Kansas	31.3	63,938
Kentucky	31.6	54,555
Louisiana	34.9	49,973
Maine	28.2	58,663
Maryland	29.6	86,223
Massachusetts	23.3	86,345
Michigan	30.7	60,449
Minnesota	27.6	71,817
Mississippi	35.5	42,781
Missouri	30.2	61,726
Montana	26.4	57,679
Nebraska	30.2	67,575
Nevada	27.7	61,864
New Hampshire	27.4	81,346
New Jersey	26.9	74,176
New Mexico	28.4	48,283
New York	27	67,274
North Carolina	29.7	53,369
North Dakota	32.2	66,505
Ohio	32.6	61,633
Oklahoma	33	54,434
Oregon	27.9	69,165
Pennsylvania	30.2	64,524
Rhode Island	27	62,266
South Carolina	32.1	57,444
South Dakota	29.8	59,463
Tennessee	31.2	56,060
Texas	31.9	59,785
Utah	25.7	77,067
Vermont	24.8	70,066
Virginia	28.5	77,151
Washington	27.3	79,726
West Virginia	35.7	50,573
Wisconsin	31.2	62,629
Wyoming	29.5	62,539

1. For the purposes of this assignment, let the x variable represent the median income for a state and let the y variable represent the obesity rate for the state. Upload the data into Descriptive Statistics for Two Quantitative Variables in Statkey to make a scatterplot of the data and include the scatterplot below and then answer the questions.
   1. Does it appear that there is a linear correlation between the median income for a state and the obesity rate? If so, is it negative or positive? Is it weak, moderate or strong?
   2. Use Statkey to calculate the correlation coefficient, r. Does this value agree with what you observed in part a?
   3. Does this data suggest that having a lower income causes obesity? If not, name at least one confounding variable that might help explain the association.

Answer 1

The scatterplot found from statkey is given below:

a) From the scatterplot, we can see that this indicates towards a linear correlation between the variables, and the correlation is moderate and negative.

b) The correlation coefficient of the data is -0.699. This agrees with the answer given in part a.

c) Yes, the data seems to suggest that having a lower income causes obesity.