Inferences Involving Means Review

Match the following notation to its meaning.

• Standard Error for the Sample Mean

• 
• Standard Deviation for the Sampling Distribution of a Sample Mean

• 
• Standard Error for the Difference Between Sample Means

• 
• Standard Deviation for the Sampling Distribution of the Difference Between Sample Means

• 

Political parties rely heavily upon polling to measure their support in the electorate. In a country with four major political parties, a poll is conducted and the Coffee Party is supported by 435 of the 1183 randomly-selected voters who were polled. To confirm, they construct a 98% confidence interval to estimate the proportion of voters who support the Coffee Party.

The Coffee Party leaders claim that they have the support of 42% of the electorate. Does your interval in suggest that this claim is plausible?

​ (a)   because the value of 0.42 ​ (b)   contained with our confidence interval.

• No, it is not plausible
• is not
• Yes, it is plausible
• is

Below are the graphs of a standard Normal distribution and a t-distribution with 2 degrees of freedom. Sketch a graph of a t-distribution with 4 degrees of freedom.

Reorder the following from narrowest (1) to widest (3).

• A

• B

• C

Below are graphical representations of three different samples from three different populations. In each case, match the picture to the most appropriate interpretation of whether or not the Normality condition for constructing a t-confidence interval has been satisfied.

• Moderately skewed right, but since n is at least 30, we should be safe using t-procedures.

• 
• Moderate-to-strong right skew & maximum value is close to being an outlier. Not advised to proceed.

• 
• Strongly skewed right, but there are no outliers. Since n is at least 30, it is safe to proceed.

• 

• Option (a)

• Option (b)

• Option (c)

• Option (d)

• Option (e)

• Option (a)

• Option (b)

• Option (c)

• Option (d)

• Option (e)

• Option (a)

• Option (b)

• Option (c)

• Option (d)

• Option (e)

• Option (a)

• Option (b)

• Option (c)

• Option (d)

• Option (e)

• Option (a)

• Option (b)

• Option (c)

• Option (d)

• Option (e)