Chapter 11 AP Statistics

To test a claim about a mean, when the population standard deviation is unknown we use:

• z procedures

• Pythagorean Theorem

• t procedures

• np > 10 and n(1-p) > 10

Margin of error equals:

• Critical Value ∗ standard Error

• z*

• 1.96

• Standard Error

When conducting a significance test for the difference in proportions, why do we pool the data when finding standard error?

• Because we like to swim

• Because we assume p1 = p2 in Ho

• Because the sample sizes are always equal

• To be safe and make sure we don't underestimate the standard error

• Because we don't the standard deviation.

When creating a confidence interval for the difference of 2 proportions, we pool the samples when finding standard error

• True

• False

Is this a probability distribution?

• No

• Yes

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

• A

• B

• C

• D

• E

What do we use to estimate unknown parameters?

• Hypothesis Test

• Confidence Interval

• Trig Identity

• Guess and check

Which statements below about least-squares regression are correct?

• Only I

• Only II

• Only III

• Both II and III

• I, II, and III

You are interested in predicting the cost of heating houses on the basis of how many rooms the house has. A scatterplot of 25 houses reveals a strong linear relationship between these variables, so you calculate a least-squares regression line. “Least-squares” refers to

• Minimizing the sum of the squares of the 25 houses’ heating costs.

• Minimizing the sum of the squares of the number of rooms in each of the 25 houses.

• Minimizing the sum of the products of each house’s actual heating costs and the predicted heating cost based on the regression equation.

• Minimizing the sum of the squares of the difference between each house’s heating costs and number of rooms.

• Minimizing the sum of the squares of the residuals.