Calculate the lower and upper control limits, Basic Statistics

Question:

Data entry clerks at ARCO key in thousands of insurance records each day.  They have just completed a new training program and want to establish a control chart based on the results of this training.  Each day random samples of the work of the clerks were collected.  The results are shown in the table below.  Two hundred records were sampled daily and examined for errors.  The number of records with errors was counted.

Day

      Number of Records with Errors

Day

Number of Records with Errors

1

12

11

12

2

8

12

10

3

4

13

8

4

6

14

10

5

8

15

10

6

8

16

8

7

6

17

10

8

6

18

11

9

2

19

9

10

4

20

8

a) You want to set control limits for the proportion of records with errors.  Assume that the past twenty days performance is adequate for establishing the control limits and performing the analysis.  Using 95% control limits, what are the upper and lower control limits for the proportion of records with errors?  Calculate your proportion defective and the lower and upper control limits to 3 decimal places (0.xxx).

b) Plot the control chart and the sample values.

c)  What would you conclude about the process, in other words, is the process in control?  Explain your decision.

d)  Suppose the industry's lower and upper control limits are 0.020 and 0.050 respectively.  What can this insurance company conclude about its process relative to the industry standards?

Posted Date: 2/18/2013 12:57:23 AM | Location : United States







Related Discussions:- Calculate the lower and upper control limits, Assignment Help, Ask Question on Calculate the lower and upper control limits, Get Answer, Expert's Help, Calculate the lower and upper control limits Discussions

Write discussion on Calculate the lower and upper control limits
Your posts are moderated
Related Questions
Ten students are given coaching for environmental statistics. The score obtained in tests 1 and 5 are given below: Sl No of student 1 2 3 4 5 6 7 8 9 10 Marks in 1st test 50 52 53

This type of sampling is also known as chance sampling or probability where each and every item in the population has an equal change of inclusion in the sample and one of the poss

The waiting time for an incoming call at the front desk of mathematics Department follows an exponential distribution. During business hours, the average of the waiting times is 10

Q1.(i)   A manufacturing firm has previously sequenced its jobs using the "Shortest Operation Time" (SOT) rule.  This has resulted in poor delivery performance with many jobs being

why is net profit always greater in absorption costing than in direct costing?

Fertility:  In order to study at which speed, at which the population is increasing, fertility rates are used which are of various types? Important among these are: Crude birth rat

1. (i) Complaints were made about the level of pollutants in the discharge from a certain factory.  The factory refuted the complaints by showing the results of their own analysis

told my friend I would help on a test, and now, think its beyond me LOL...want to save face, can you help me?

An internal report issued by the marketing manager of a oil-change franchise claims that the mean number of miles between oil changes is for franchise customers is at least 3600 mi