Chapter 1 Practice

How do you feel about Chapter 1?

• I think I got it. I understand the practice problems.

• I got it for the main part.

  I think doing the practice problems in class will help.

• I feel very confident about chapter 1.

• I do not understand what is going on.

A ​ _____ is a subset of a ​ population containing the individuals that are actually observed.

Match the following

• Sample Calculations

• Parameter

• Population Calculations

• Data

• All Object of Interest

• Statistic

• Facts collected about object of interest

• Population

• Characteristic of interest

• Variable

A ​ (a)   variable is a quantitative variable whose possible values can be listed. The values for such variable are ​ (b)   .

• discrete
• whole numbers
• continuous
• uncountable
• nominal
• ordinal
• fractions

Another name for categorical variables is :

• Continuous variables
• Qualitative variables
• Quantitative variables
• Interval variables

1.They randomly select 9 schools and interview all of the teachers in those schools. 

• Simple Random Sample

• Cluster Sample

• Stratified Sample

• Systematic Sample

• Convenience Sample

The school board could take a list of all teachers listed alphabetically, assign each teacher a three digit number, and randomly select 100 teachers to interview.

• Simple Random Sample

• Cluster Sample

• Stratified Sample

• Systematic Sample

• Convenience Sample

The school board decides that the teachers at different school levels will have a different opinion. This district has 30 elementary schools, 10 middle schools and 5 high schools.  Therefore, they design the study so that they randomly select 6 elementary schools, 2 middle schools and 1 high school (20% of each type) and interview all of the teachers of those selected schools. 

Hint: This is a multistage sampling, meaning you have more than one sampling method used.

• Simple Random Sample

• Cluster Sample

• Stratified Sample

• Systematic Sample

• Convenience Sample

Answer explanation

This is a multistage sampling, meaning you have more than one sampling method used.

Stratified Sample: We have 3 strata (elementary, middle, and high schools). We then randomly select 20% of each.

Cluster Sample: We then interview ALL teachers from these groups.

For each definition/description given, identify the term that it represents.

• Parameter 

• A number that describes the population

• Quantitative Variable

• A quantitative variable whose possible values can be listed.

• Sampling Bias

• An error in gathering data that makes the results questionable as to its usefulness in evaluating the observation.

• Discrete Variable 

• A variable that tells how much or how many of something there is

A newspaper reporter decided to sample residents of all major metropolitan areas in the entire country.  This sampling asked if the residents liked living in their city, or are they considering moving, and if so, where?  Unfortunately, this survey went over budget and was stopped and only the East coast was adequately interviewed.  With regards to having this survey labeled as representing the entire country what, if any, will be the most noticeable bias for this survey as it is now?

• Voluntary response bias 

• Undercoverage of the population

  (Sampling Bias)

• There does not seem to be any bias 

• Self-interest bias