A Large City Installed LED Streetlights,in Part,to Help Reduce Crime

question 112

Essay

A large city installed LED streetlights,in part,to help reduce crime in particular areas.The city collected the number of property crimes along nine randomly selected streets in the month before and after the LED light installation,and claims that crime has been reduced.The crime data is shown in the table. a.Specify the competing hypotheses to test the city's claim.
b.Calculate the value of the relevant test statistic and find the critical value at the 5% significance level.
c.Does the evidence support the city's claim at the 5% significance level?

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Definitions:

Hypothesis

An if–then statement of conjecture that relates variables to one another and is used to reflect the general problem statement or question that is the motivation for asking a research question.

Directional Research Hypothesis

A research hypothesis that posits a difference between groups in one direction.

Nondirectional Research Hypothesis

A research hypothesis that posits a difference between groups but not in either direction. See Directional Research Hypothesis.

Null Hypothesis

A hypothesis that there is no significant difference or effect, serving as the default assumption that is tested against.