Question

Question 1: (1 point)

Identify the independent and dependent variables in each example below.

Environmentalists have a theory that as smoke-stack and tailpipe emissions have increased over the past centuries, global warming has occurred.

An educational researcher is interested in effects of nutrition on school performance. She classifies students as breakfast eaters and non-breakfast eaters. She measures school performance by recording school attendance rate.

Question 2: (2points)

At what level of measurement is the following data and what type of graph can be used?

SAT scores of students collected from a sample of students in Berkeley College.

A meteorologist classifies cities in the US as having winter weather as dreary, not dreary.

A kindergarten teacher classifies students as readers, incipient readers, nonreaders.

A housing developer advertises his houses as being fully carpeted, partially carpeted or not carpeted

Question 3: (2 points)

The college registrar is asked to count the number of usable chairs in different classrooms at her university to determine how many students can be seated in each class. These are number of usable chairs in the different classrooms:

7, 12, 26, 18, 20, 33, 34, 17, 20, 35, 46, 50, 28, 29, 33, 18, 45, 53, 30, 37, 45, 58, 43, 42, 10, 34, 28, 35, 36, 50, 60, 55, 45, 52, 54, 28, 34, 25, 35, 40, 45, 44, 40, 23, 38, 39, 40, 50, 60, 45, 36, 28, 40, 54, 62, 44, 24, 28, 30, 60, 38, 58, 24.

At what level of measurement is this data & what type of graph is appropriate?

Make steam-and-leaf display

Describe modality & symmetry (skewness) of this data

Answer 1

Question 1:
A. Environmentalists have a theory that as smoke-stack and tailpipe emissions have increased over the past centuries, global warming has occurred -> Independent variable : smoke stack and tail pipe emissions
Dependent variable : Global warming
B.An educational researcher is interested in effects of nutrition on school performance. She classifies students as breakfast eaters and non-breakfast eaters. She measures school performance by recording school attendance rate -> Independent variable : Attendance rate
Dependent variable : Categorical variable (1/2, 1 - breakfast eaters, 2 - non-breakfast eaters) [For linear regression, it can be made as 1/0 also]
Question 2:
A.SAT scores of students collected from a sample of students in Berkeley College : Interval scale ( since the difference between values is significant and here, '0' doesn't indicate that the student has no knowledge )
Graph - Histogram
B.A meteorologist classifies cities in the US as having winter weather as dreary, not dreary : Nominal scale ( since classification is categorical and has no natural ordering )
Graph - Bar/pie chart
C. A kindergarten teacher classifies students as readers, incipient readers, nonreaders : Ordinal scale ( since the classification is categorical and has natural ordering )
Graph - Bar/pie chart
D. A housing developer advertises his houses as being fully carpeted, partially carpeted or not carpeted : Ordinal scale ( since the classification is categorical and has natural ordering )
Graph - Bar/pie chart