The state and local police departments are trying to analyze crime rates so they can shift their patrols from decreasing-rate areas to areas where rates are increasing. The city and county have been geographically segmented into areas containing 5,000 residences. The police recognize that not all crimes and offenses are reported: people do not want to become involved, consider the offenses too small to report, are too embarrassed to make a police report, or do not take the time, among other reasons. Every month, because of this, the police are contacting by phone a random sample of 800 of the 5,000 residences for data on crime. (Respondents are guaranteed anonymity.) Here are the data collected for the past 12 months for one area: Month Incidents Sample Size January 13 800 February 7 800 March 12 800 April 8 800 May 13 800 June 7 800 July 8 800 August 12 800 September 10 800 October 14 800 November 10 800 December 8 800 a. Determine the , ,UCL and LCL for a p-chart of 95 percent confidence (at Z = 1.96) b. Plot the P-chart c. If the next three months show crime incidences in this area as January = 10 (out of 800 sampled) February = 12 (out of 800 sampled) March = 11 (out of 800 sampled) Do you think the process is under control?
The state and local police departments are trying to analyze crime rates so they can shift their patrols from decreasing-rate areas to areas where rates are increasing. The city and county have been geographically segmented into areas containing 5,000 residences. The police recognize that not all crimes and offenses are reported: people do not want to become involved, consider the offenses too small to report, are too embarrassed to make a police report, or do not take the time, among other reasons. Every month, because of this, the police are contacting by phone a random sample of 800 of the 5,000 residences for data on crime. (Respondents are guaranteed anonymity.) Here are the data collected for the past 12 months for one area:
|
Month |
Incidents |
|
|
January |
13 |
800 |
|
February |
7 |
800 |
|
March |
12 |
800 |
|
April |
8 |
800 |
|
May |
13 |
800 |
|
June |
7 |
800 |
|
July |
8 |
800 |
|
August |
12 |
800 |
|
September |
10 |
800 |
|
October |
14 |
800 |
|
November |
10 |
800 |
|
December |
8 |
800 |
a. Determine the , ,UCL and LCL for a p-chart of 95 percent confidence (at Z = 1.96)
b. Plot the P-chart
c. If the next three months show crime incidences in this area as
January = 10 (out of 800 sampled)
February = 12 (out of 800 sampled)
March = 11 (out of 800 sampled)
Do you think the process is under control?
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 4 images
