Statistical Studies and Sampling Methods

A ___ is a large group that includes everything being studied.

• Sample
• Stratified Sampling Method
• Population
• Voluntary-Response

A ___ is a small portion of the population used to gather data from.

• Systematic Sampling Method
• Sample
• Population
• Bias

Marianne wanted to know students' opinion on the new schedule at school. So she randomly selected 2 students from each class during second period. 
This is a form of:

• Convenience Sampling
• Random Sampling
• Stratified Sampling
• Systematic Sampling

Why do we randomly select our samples?

• to control every aspect
• reduce bias
• so we don't get the same answers from everyone
• because it is easier to do

A teacher wants to know the average time spent doing homework by the students in her class of 20 girls and 5 boys.
She randomly selects 5 students.

• Convenience Sampling
• Systematic Sample
• Stratified Sample
• Random Sample

Biased or Unbiased?
Carlos wants to know the favorite sport of people at his school so he asks his baseball team.

• Biased
• Unbiased

A teacher wants to know the average time spent doing homework by the students in her class of 20 girls and 5 boys.
She selects a random student to start then picks the student in every 5th seat.

• Random
• Systematic
• Voluntary Response
• Stratified

The principal of a high school wants to know if male students or female students are late to school more often.  He separates the students by gender, then randomly chooses a group of 30 male students, then a group of 30 female students.  This is an example of 

•  random sampling
• Stratified sampling
• Voluntary-Response
• systematic sampling

To find out what the preferred ice cream flavor is, wait outside an ice cream parlor and ask every 4th person leaving the store to name his or her favorite flavor until you get 25 responses is an example of...

• Voluntary-Response
• Random Sample
• Stratified Sample
• Systematic Sample

To avoid working late, the quality control manager inspects the last 10 items produced that day.

• Convenience

• Random

• Self Selected

• Systematic