Quality Management
In the contemporary business environment, business control chart is very critical to enhance continuous business process and business improvement. The use of statistical process control charts (SPC) is very critical to enhance improvement and quality of products and service. Process control chart is a statistical tool that allows business to record data regarding the performances of business process on a regular basis. The data may be recorded hourly, weekly or on daily basis. The major objective for using SPC is to compare the present product performances with the past product performances and allow a business to prevent defective materials. Thus, SPC is powerful tool to enhance continuous business improvement. (Harrington, 2009).
Objective of this paper is to use the control chart process to determine the weekly sales process of Ford Motor Company.
X Bar and R. Process Control Charts for Weekly Sales of Ford Motor
The charts are produced from the data collected referred to X-Bar and R. chart. X-Bar is calculated from the average of 18-week sale's sample while the R. is the range between the highest and lowest sample of data. The main objective of this chart is to measure the variations within the samples as well as comparing those variations between the samples. If the variations are consistence with the sample variations, the process is predictable and is in control.
The paper uses the X Bar R. Chart technique because this process is ideal statistical process control. This technique takes the sample data and calculates the average or the arithmetic mean, and measure the difference between the largest and the smallest sample. As being revealed in Table 1, the paper provides the 18-week sales of Ford auto-car to determine the R. Chart.
Table 1: 18-Week Sales
Weekly Sales X and R. chart
Weekly Sales X
1
104,679
2
115,537
3
134,696
4
177,393
5
205,437
6
184,038
Using this data, the paper calculates the moving average as being revealed in Table 2.
Table 2: Moving Average
Weekly Sales X and R. Chart
Weekly Sales X
Moving Range R
1
104,679
2
115,537
10,858
3
134,696
19,159
4
177,393
42,697
5
205,437
28,044
6
184,038
21,399
7
105,863
78,175
8
163,746
57,883
9
183,134
19,388
10
205,348
22,214
11
265,599
60,251
12
197,901
67,698
13
113,093
84,808
14
219,758
106,665
15
192,949
26,809
16
174,363
18,586
17
80,148
94,215
18
212,387
132,239
Process Average
168,671
52,417
From the table 2, R-Bar is equal to 52,417 revealing that the process is in control. The paper calculates the control limit to determine whether the process is in control. The control limits are…
