The following statistics represent crime rates per 1000 population for a random sample of 46 Denver neighborhoods. The mean crime rate, 64.2 and standard deviation, s 27.9 crimes per 1000 population a) Let us say that the data are representative of the population crime rates in Denver neighborhoods. (i) Compute the margin of error, E for an 80% confidence interval for u, the population mean crime rate for all Denver neighborhoods (i1) Compute an 80% confidence interval for u, the population mean crime rate for all Denver neighborhoods. b) Suppose you are advising the police department about police patrol assignments. One neighborhood has a crime rate of 57 crimes per 1000 population. Do you think that this rate is below the average population crime rate and that fewer patrols could safely be assigned to this neighborhood? Explain Use the confidence interval to justify your answer. c) Another neighborhood has a crime rate of 75 crimes per 1000 population average? Does this crime rate seem to be higher than the population average? Would you recommend assigning more patrols to this neighborhood? Explain. Use the confidence interval to justify your answer.

The following statistics represent crime rates per 1000 population for a random sample of 46 Denver neighborhoods. The mean crime rate, 64.2 and standard deviation, s 27.9 crimes per 1000 population a) Let us say that the data are representative of the population crime rates in Denver neighborhoods. (i) Compute the margin of error, E for an 80% confidence interval for u, the population mean crime rate for all Denver neighborhoods (i1) Compute an 80% confidence interval for u, the population mean crime rate for all Denver neighborhoods. b) Suppose you are advising the police department about police patrol assignments. One neighborhood has a crime rate of 57 crimes per 1000 population. Do you think that this rate is below the average population crime rate and that fewer patrols could safely be assigned to this neighborhood? Explain Use the confidence interval to justify your answer. c) Another neighborhood has a crime rate of 75 crimes per 1000 population average? Does this crime rate seem to be higher than the population average? Would you recommend assigning more patrols to this neighborhood? Explain. Use the confidence interval to justify your answer.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

Traffic Highway planners investigated the relationshipbetween traffic Density (number of automobiles per mile)and the average Speed of the traffic on a moderately largecity thoroughfare. The data were collected at the samelocation at 10 different times over a span of 3 months.They found a mean traffic Density of 68.6 cars per mile(cpm) with standard deviation of 27.07 cpm. Overall, the cars’ average Speed was 26.38 mph, with standard devia-tion of 9.68 mph. These researchers found the regression line for these data to be Speed = 50.55 - 0.352 Density.a) What is the value of the correlation coefficientbetween Speed and Density?b) What percent of the variation in average Speed isexplained by traffic Density? c) Predict the average Speed of traffic on the thorough-fare when the traffic Density is 50 cpm. d) What is the value of the residual for a traffic Densityof 56 cpm with an observed Speed of 32.5 mph?e) The data set initially included the point Density =125 cpm, Speed = 55 mph. This…
Total blood volume (in ml) per body weight (in kg) is important in medical research. For healthy adults, the red blood cell volume mean is about µ = 28 ml/kg with a standard deviation of 4.75ml/kg. Red blood cells volume that is too low or too high can indicate a medical problem. Suppose he does a hypothesis test with a significance level of 0.01. Roger has had seven blood tests and the red blood cell volumes were: 32 25 41 35 30 37 29 Roger’s null hypothesis is that his blood tests are normal and that his alternative hypothesis is that something is wrong. Symbolically, the null and hypotheses are as follows Ho: µ = 28 ml/kg and Hi: µ ≠ 28 ml/kg What value of the test statistic (z) should he report? (Sampling a Normal Distribution for the Mean µ) Group of answer choices a. 0.99 b.2.42 c.2.62 d.2.22
Is there strong evidence of global warming? Let’s consider a small scale example, comparing how temperatures have changed in the US from 1968 to 2008. The daily high temperature reading on January 1 was collected in 1968 and 2008 for 51 randomly selected locations in the continental US. Then the difference between the two readings (temperature in 2008 - temperature in 1968) was calculated for each of the 51 different locations. The average of these 51 values was 1.1 degrees with a standard deviation of 4.9 degrees. We are interested in determining whether these data provide strong evidence of temperature warming in the continental US. (d) Calculate the test statistic and find the p-value. (e) What do you conclude? Interpret your conclusion in context. (f) Calculate a 90% confidence interval for the average difference between the temperature measurements between 1968 and 2008. Interpret this interval in context. (g) Does the confidence interval provide convincing evidence that the…
This research was conducted with Korean adolescents in the Los Angeles area. Would you be willing to generalize the results of this study to Korean adolescents who live in other regions of the country? Why or why not.
The mean change in muscle thickness observed after a 4-week training regimen was 4 mm, and the 95% confidence interval (CI) for mean change was (-0.5, 8.5). Which is the best scientific conclusion for the effectiveness of this regimen ?
omeb... Kaiser Permanent... /courses/27422/discussion_topics/357765 F2 W Instructions 30F Required parameters: Confidence level: F #3 0.95 Standard deviation: 7.9 E Number of Hours Worked An economic researcher is collecting data about grocery store employees in a county. The data listed below represents a random sample of number of hours worked by 40 employees for several grocery stores in the county. Assume that the population standard deviation is 7.9 hours. An economics researcher wants to estimate the mean number of hours worked by all grocery store employees in the county. How many employees must be included in the sample to be 95% confident that the sample mean is within 1.5 hours of the population mean? 30, 26, 33, 26, 26, 33, 31, 31, 21, 37, 27, 20, 34, 35, 30, 24, 38, 34, 39, 31, 22, 30, 23, 23, 31, 44, 31, 33, 33, 26, 27, 28, 25, 35, 23, ,32, 29, 31, 25, 27 Find the minimum sample size to estimate the population mean hours worked using StatCrunch. 1. Enter data in…
On a measure of running speed on a 100 meter dash, students received timed scores ranging from 12 seconds to 24 seconds. The distribution of running times is normative with a mean of 16 seconds. Transferring this ratio data to standard scores for comparison with the results of classes from other departments, the mean score is assigned a standard score of 100 with a standard deviation of 10. From this example, a standard score of 99 would mean the actual value in seconds for an individual would be about a. 16 b. 12 c. 19 d. 24
Has the number of shoppers who wear masks changed from 2020 to 2021? There are arguments for and against this question. The mean number of masks, u, used by a shopper in Metropolis in 2020 will be compared to the mean number of masks, Hy used by a shopper in Metropolis in 2021. The true values of u, and u, are unknown. It is recognized that the true standard deviations are o, = 19 for the 2020 measurements and o, = 24 for the 2021 measurements. We take a random sample of m = 255 shoppers in 2020 and a random sample of n = 200 shoppers in 2021. The mean number of masks were x= 97 for 2020 and y= 85 for 2021. Assuming independence between the years and assuming masks used by shoppers are normally distributed we would like to estimate x - Hy. What is the standard deviation of the distribution of x? What is the standard deviation of the distribution of x - y? Create a 95% confidence interval for uy - Hy ? ) What is the length of the confidence interval in part c) ? If we let n stay at 200…
A sample of 33 lights in Austin gives an average of 46 cars/min while the city SD=3.4 A sample of 34 Dallas lights give a mean of 44 cars/mim with the city SD=1.4 At the 91% level, do the towns differ? 1. Is the test (A-Left Tailed, B-Right Tailed, C-2-Tailed) (separate with comma if there are 2) 2. Critical Value 3. Test statistic 4. 3-decimal p-Value
PLEASE ONLY SELECT THE ANSWERS AS SHOWN FOR THE MULTIPLE CHOICE, SUCH AS OPTION 1, 2, ETC. 1) In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with raw garlic. Cholesterol levels were measured before and after the treatment. The changes (before minus after) in their levels of LDL cholesterol (in mg/dL) have a mean of 0.8 and a standard deviation of 1.51. Use a 0.10 significance level to test the claim that with garlic treatment, the mean change in LDL cholesterol is greater than 0. What do the results suggest about the effectiveness of the garlic treatment? Assume that a simple random sample has been selected. Identify the null and alternative hypotheses, test statistic, P-value, and state the final conclusion that addresses the original claim. What are the null and alternative hypotheses? A. H0: μ=0 mg/dL H1: μ<0 mg/dL B. H0: μ>0 mg/dL H1: μ<0 mg/dL C. H0: μ=0 mg/dL H1: μ≠0 mg/dL D. H0: μ=0 mg/dL H1: μ>0 mg/dL…
Please answer the incorrect ones only.
An investigation of the relationship between traffic flow (measured in cars per day) and lead content (measured in micrograms per gram of dry weight) in the bark of trees near the highway yielded the following summary statistics: Sample Mean Sample Standard Deviation Lead Content (micrograms per gram dry weight) y¯=y¯= 680 sysy = 240 Traffic Flow (cars / day) x¯=x¯= 1750 sxsx = 800 The correlation between lead content and traffic flow was found to be r = 0.6 and a scatterplot showed the form to be linear. Since Traffic flow is the X-variable, its mean and standard deviation have been labelled x¯ and sxx¯ and sx. Since Lead content is the Y-variable, its mean and standard deviation have been labelled y¯ and syy¯ and sy . Determine slope and y-intercept of the least squares regression line for using X to predict Y. Group of answer choices Slope y-intercept