Stratified Sampling

Disneyland often surveys its guests as they exit a restaurant during their visit. The surveyor stands at the restaurant exit, counts the number of people leaving, and surveys every 25th guest.
This is a form of:

• Simple Random Sample
• Stratified Random Sample
• Voluntary Response
• Systematic Random Sampling

An independent research company wants to go door to door to survey people in the city of Fontana. The company decides to number all blocks within the city limit, randomly choose 1 block and survey all households on that block.

This is an example of:

• Simple Random Sample

• Stratified Random Sample

• Cluster Random Sample

• Systematic Random Sampling

A teacher wants to know how well her students are doing on a topic. She randomly picks one class to survey.

• Simple Random

• Cluster

• Stratified

• Systematic

A teacher splits her classes up by period. She then randomly picks 3 students from each period to do a survey.

• Stratified.

• Systematic

• Cluster

• Biased.

This sample is selected by dividing the population into subgroups and then taking a fixed number of units from each group using the simple random sample.

• stratified
• cluster
• judgment
• experimental

Units of the population are grouped; one or more groups are selected at random.  All units of that group are included in the sample.

• cluster sample
• simple random
• stratified
• proportional

Identify the sampling design: The LFCC registrar wants to investigate attitudes of their graduates.  The registrar randomly selects 100 names from each of the four past graduating classes.

• cluster
• volunteer
• stratified
• simple random

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

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