Problem 13-11 (Algo)

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 1,070 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	CRIME INCIDENCE	SAMPLE SIZE	CRIME RATE
January	9	1,070	0
February	11	1,070	0
March	9	1,070	0
April	9	1,070	0
May	9	1,070	0
June	11	1,070	0
July	9	1,070	0
August	12	1,070	0
September	10	1,070	0
October	13	1,070	0
November	10	1,070	0
December	9	1,070	0

a. Determine the PP , S_p,UCL and LCL for a p-chart of 95 percent confidence (at Z = 1.96). (Round your answers to 5 decimal places.)

b. If the next three months show crime incidences in this area as

January = 10 (out of 1,070 sampled)

February = 12 (out of 1,070 sampled)

March = 11 (out of 1,070 sampled)

What comments can you make regarding the crime rate?

multiple choice

• The process is in control.
• The process is out of control.