AP Statistics Review # 2

The smaller the p-value, the stronger the evidence against the _____________ hypothesis

• null
• alternative

If the p-value is less than α, we reject H₀

• True
• False

A hypothesis test is performed and
p-value = 0.02. Which is the best conclusion?

• H₀ is rejected at α = 0.01.
• H₀ is rejected at α = 0.05.
• Ha is rejected at α = 0.01.
• Ha is rejected at α = 0.05.

Which of the following is an appropriate interpretation of a p-value?

• The probability of rejecting H₀, when we should have failed to reject H₀.
• The probability of failing to reject H₀, when we should have rejected H₀.
• Assuming H₀ is true, it is the probability of obtaining our sample statistic or a more extreme value.
• Assuming H₀ is NOT true, it is the probability of obtaining our sample statistic or a more extreme value.

Observed in the wild are 10 circles, 20 squares and 30 triangles. The ratio for this particular population is 2:3:5 
observed: 10 circles     expected: 12
observed 20 squares    expected : 18
observed 30 triangles   expected: 30
What is the degrees of freedom?

• 1
• 2
• 3
• 4

What are the degrees of freedom for the following χ² test?

• 6
• 2
• 5
• 36

What must be true about the expected values in a chi square test?

• greater than or equal to 2
• greater than or equal to 5
• greater than or equal to 10
• greater than or equal to 30

Which test would you use to see if people on computers and people on handhelds use the same Internet search engines?  1000 web searches from a computer and 1500 web searches from a hand held were tracked to see what search engine was used.

• Chi-square Goodness of Fit Test
• Chi-Square Test for Homogeneity
• Chi-Square Test for Independence/Association
• Not a Chi-square test

Which test would you use to see if gender is a factor choosing a person’s favorite fruit?  900 college students were surveyed and their favorite fruit recorded.

• Chi-square Goodness of Fit Test
• Chi-Square Test for Homogeneity
• Chi-Square Test for Independence/Association
• Not a Chi-square test

Which test would you use to see whether the fans that buy tickets are demographically the same as the general population of the city.  Currently 42% are Caucasian, 35% are Hispanic, 12% are African American, 8% are Asian, and the rest are defined as other.

• Chi-square Goodness of Fit Test
• Chi-Square Test for Homogeneity
• Chi-Square Test for Independence/Association
• Not a Chi-square test