A Sample of 30 Year Fixed Mortgage Rates at 12

question 5

Multiple Choice

A sample of 30 year fixed mortgage rates at 12 randomly chosen credit unions yields a mean rate of 6.65 % and a sample standard deviation of 0.38%. A sample of 30 year
Fixed mortgage rates at 16 randomly selected banks yields a mean rate of 7.05% and a
Sample standard deviation of 0.22%. Are the mean rates different between credit unions
And banks? Relevant output is shown below. Which of the following is true? $\begin{array} { l r r r r } \text { Sample } & \mathbb { N } & \text { Mean } & \text { StDev } & \text { SE Mean } \\ 1 & 12 & 6.650 & 0.390 & 0.11 \\ 2 & 16 & 7.050 & 0.220 & 0.055 \end{array}$
Difference $= m u ( 1 ) = m u$ (2)
Bstimate for difference: $\quad - 0.400$
95 옿 CI for difference: $( - 0.666 , - 0.134 )$
T-Test of difference $= 0$ (vs not $= ) :$ T-Value $= - 3.19$ P-Value $= 0.006 \quad$ DF $= 16$

• A) This is a paired design.
• B) This is a test of two means from independent samples.
• C) This is a one tailed test.
• D) Both A and C.

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Definitions:

Memory Test

A method or tool used to evaluate an individual's ability to remember information.

Control Group

A control group in scientific experiments is the group of participants who do not receive the experimental treatment and are used as a benchmark to measure the effect of the treatment.

Hindsight Bias

The tendency to believe, after learning an outcome, that one would have predicted it or known it was inevitable, often referred to as the "I-knew-it-all-along" effect.

Predictable Events

Occurrences or actions that can be anticipated or expected based on existing knowledge, patterns, or trends.