Question
In: Statistics and Probability
Suppose you are interested in studying regional differences in crime. You take a random sample of 100...
Suppose you are interested in studying regional differences in crime. You take a random sample of 100 cities in the South, and find a mean crime rate of 55 with a sample varianceof 5.78. A sample of 100 cities in the North has a mean crime rate of 50 with a sample varianceof 6.72.
1. Construct a 95% confidence interval around the difference in crime rates between the population of Southern cities and the population of Northern cities.
2. Interpret, in words, the meaning of this interval.
3. Test the null hypothesis that the mean crime rate for the population of cities in the South is less than (or equal to) the mean crime rate for the population of cities in the North. Use a significance level of .01.
Solutions
orchestra answered 2 years agoRelated Solutions
Suppose you are interested in studying regional differences in crime. You take a random sample of 100...
Suppose you are interested in studying
regional differences in crime. You take a random sample
of 100 cities in the South, and find a mean crime rate of 55 with a
sample varianceof 5.78. A sample of 100 cities
in the North has a mean crime rate of 50 with a sample
varianceof 6.72.
1. Construct a
95% confidence interval around the difference in crime rates
between the population of Southern cities and the population of
Northern cities.
2. Interpret, in words, the
meaning...
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µ.
(a) Calculate a 90% confidence interval for µ.
(b) Calculate a 95% confidence interval for µ.
(c) Based on (a) and (b), comment on what happens to the width
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confidence level.
(d) Suppose your sample size...
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A sociologist is studying the prevalence of crime in one major city. In a sample of...
A sociologist is studying the prevalence of crime in one major
city. In a sample of 150 randomly selected residents, 54 say that
they have been victimized by a criminal. Based on this sample,
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. A sociologist is interested in studying the relationship between education and crime. She randomly selects...
. A sociologist is interested in studying the relationship
between education and crime. She randomly selects 312 people and
asks them their education level and whether or not they have ever
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Education
Level
No Felony Conviction Felony
Conviction
Less than 9
years
89
10
9 years - 12
years
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10
12 years - 16
years
59
6
16+
years
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7
b. State the...
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From univariate to bivariate
Suppose you are interested in studying the effect of education
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You propose the following regression of annual salary on years
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wage=β0 +
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exper = work experience
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business majors. This list is 22 pages long and contains the names
of 2,200 business majors....
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