Sampling Inference

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

See the image.

• 15 Students

• 25 Students

• 30 Students

• 50 Students

• All students at her lunch table

• Every 15th student who enters school in the morning

• All students on her bus

• All 7th graders

Answer the question above.

• 5

• 13

• 80

• 200

What inference can you draw from this survey?

• I can infer that most students in this school like pizza.

• I can infer that very few students like hamburgers.

• I can infer that their favorite is corn dogs.

• I can infer that most students in this school like hamburgers.

A travel club has 3,000 members. A random sample of 50 of the club members found that 12 people like mountain vacations best. Which statement is NOT supported by the sample data?

• Twenty-four percent of those sampled say they like mountain vacations best.

• An estimated 720 club members would likely say they enjoy mountain vacations best.

• Almost one-quarter of club members would likely say they enjoy mountain vacations best.

• More than 2,500 club members would likely say they prefer other vacations over mountain vacations.

True or False: all samples lead to a good prediction about an entire population.

• True

• False

Answer the questions above.

• 123

• 156

• 36

• 64

What inference can be made about the populations based on Paisley's data?

• young teachers drive trucks

• SUVs are driven by teachers with families

• most teachers drive sedans

• fewer teachers drive sedans than SUVs

Make a comparative inference based on the mean values of each data set.

• On average, 6th graders completed the fewest assignments

• On average, 6th graders completed the most assignments

• On average, 7th graders completed the fewest assignments

• On average 8th graders completed the fewest assignments