CLASS PRESENTATION

(a) What are the hypotheses for evaluating whether poverty percentage is a significant predictor of murder rate?

H0 = The poverty percentage is NOT a significant predictor of murder rate
HA = The poverty percentage is a significant predictor of murder rate.

formal expression
H0 : β1 = 0
HA : β1 ≠ 0

(b) State the conclusion of the hypothesis test from part (a) in context of the data.

Based on the table above, the p-value for this test is approximately 0, that is why we reject H0.
The data shows convincing evidence that poverty percentage is a significant predictor of murder rate.

(c) Calculate a 95% confidence interval for the slope of poverty percentage, and interpret it in context of the data.

A 95% confidence interval is calculated using a T-distribution, with a degree of freedom of 18.
The equation would be [(poverty %)±(2.10 * SE)] using the t- value from the t- probability table.

2.559 + 2.10*0.390
## [1] 3.378
2.559 - 2.10*0.390 
## [1] 1.74
Results:

For each percentage point poverty is higher, murder rate is expected to be higher on average by 1.74 to 3.378 per million.

(d) Do your results from the hypothesis test and the confidence interval agree? Explain.

Yes, the H0 was rejected and the confidence interval does not include 0.