Sampling, Bias, & Variability

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

Tags

CCSS.HSS.IC.B.3

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

Tags

CCSS.7.SP.A.1

CCSS.HSS.IC.A.1

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.

Tags

CCSS.HSS.IC.B.3

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

Tags

CCSS.HSS.IC.B.3

Identify the sampling design: Mr. Rhoades puts all of his students' names in a hat and randomly selects one without looking.

• cluster
• volunteer
• systematic
• simple random

Tags

CCSS.HSS.IC.B.3

Identify the sampling design: School admin conducted a survey on post-graduation plans.  Students of senior class 2018 were listed in order by class rank.  The school selected a random number between 1 and 15, obtaining a number 11.  Then, they selected every 11th student for the survey.

• cluster
• volunteer
• systematic
• simple random

Tags

CCSS.HSS.IC.B.3

At a middle school, the 7th graders will conduct a survey for where to go on a field trip. Which method will result in the least biased decision?

• to randomly ask 8th grade students who went on a field trip last year
• to randomly choose some 7th grade students to select a location
• to ask all 7th grade teachers and administrators for a location
• to ask the student council to choose a location

Tags

CCSS.7.SP.A.1

CCSS.HSS.IC.A.1

How do we reduce variability?

• Increase randomness.

• Increase sample size.

• Decrease randomness.

• Decrease sample size.

How do we reduce bias?

• Increase variability

• Increase randomness

• Decrease randomness

• Decrease variability

Tags

CCSS.HSS.IC.B.3

Why do we want our samples to be random?

• To decrease the margin of error

• To increase our confidence

• To decrease variability

• To decrease bias

Tags

CCSS.HSS.IC.B.3