1.E: Introduction (Exercises)
 Page ID
 7086
 In your own words, describe why we study statistics.
 Answer:

Your answer could take many forms but should include information about objectively interpreting information and/or communicating results and research conclusions
 For each of the following, determine if the variable is continuous or discrete:
 Time taken to read a book chapter
 Favorite food
 Cognitive ability
 Temperature
 Letter grade received in a class
 For each of the following, determine the level of measurement:
 Tshirt size
 Time taken to run 100 meter race
 First, second, and third place in 100 meter race
 Birthplace
 Temperature in Celsius
 Answer:

 Ordinal
 Ratio
 Ordinal
 Nominal
 Interval
 What is the difference between a population and a sample? Which is described by a parameter and which is described by a statistic?
 What is sampling bias? What is sampling error?
 Answer:

Sampling bias is the difference in demographic characteristics between a sample and the population it should represent. Sampling error is the difference between a population parameter and sample statistic that is caused by random chance due to sampling bias.
 What is the difference between a simple random sample and a stratified random sample?
 What are the two key characteristics of a true experimental design?
 Answer:

Random assignment to treatment conditions and manipulation of the independent variable 9
 When would we use a quasiexperimental design?
 Use the following dataset for the computations below:
\(\mathrm{X}\)  \(\mathrm{Y}\) 

2  8 
3  8 
7  4 
5  1 
9  4 
 \(\sum \mathrm{X}\)
 \(\sum \mathrm{Y}^2\)
 \(\sum \mathrm{XY}\)
 \((\sum \mathrm{Y})^2\)
 Answer:

 26
 161
 109
 625
 What are the most common measures of central tendency and spread?
Contributors
Foster et al. (University of MissouriSt. Louis, Rice University, & University of Houston, Downtown Campus)