Samples, Bias, and Data Collection

What word does this statement describe?

A systematic error in measuring the estimate; favors certain outcomes.

• Survey

• Population

• Bias

• Sample

Is this a valid statistical question?

What proportion of New Jersey residents would choose vanilla as their favorite ice cream flavor?

• Yes! You need to collect data to answer this question.

• No! It's just a yes or no question.

Elvira assigns every student in the school a number and randomly selects 60 students to survey to determine if students at the school are satisfied with school lunch.

• Simple Random Sample

• Volunteer Sample

• Cluster Sample

• Systematic Sample

Identify the type of sampling used:

Assign each car in a dealership a number and then use a random-number table to select the cars to be inspected.

• systematic sample

• simple random sample

• convenience sample

• voluntary response sample

When a sample does not accurately represent the population it is a:

• Unbiased sample

• Biased sample

Identify the type of sampling used:

Marianne wanted to know students' opinion on the new schedule at school. She survey's the first 30 students who come into her class.

• Convenience Sampling

• Systematic Random Sampling

• Simple Random Sampling

• Volunteer response

Identify the type of sampling used:

A teacher splits her classes up by period. She then uses a RNG to select 10 students from each period to participate in a survey.

• Stratified Random Sample

• Systematic Random Sample

• Cluster Random Sample

• Biased Sample

Why do we randomly select our samples?

• for control

• reduce bias

• so we don't get the same answers from everyone

• to eliminate confounding results

16 out of the 20 people who called into a radio station said that they enjoy the station's morning programming. What type of bias is demonstrated here?

• Voluntary Response Bias

• Nonresponse Bias

• Undercoverage Bias

An employer wants to know how their 500 employees like working for them. Which is the most representative sample?

• Ask the first 75 people to show up for work

• Randomly select the names of 10 employees

• Poll the Employees of the Month for the past year

• Randomly select the names of 75 employees