Discussion 18-2
- What was Shewharts’s source for the data required for his statistical process control?
Shewhart’s source for data needed for his statistical process control was the mean and the R-charts that provided certain kinds of data. In this source of data, some measurements procedures are involved. The other source of data used in SPC is that derived from the P-chart whose data has differing attributes from the mean and R-charts. These two principal sources of data fall into the two broad categories of data used in the SPC process, which are; the variables involving measured values and the attributes concerning counted values. Other sources falling under these categories are u-chart, c-chart, medians, and range. Control limits and fraction defective by subgroup are also used in generating the data required in the SPC process.
- Shewhart describes two kinds of variation, that resulting from common causes and that resulting from special causes. Define both.
In explaining the SPC process, Shewhart describes the two different types of variations arising from common causes and special causes. Special variation in the context of SPC refers to the factors or elements that are not required in the work process; they are the items that have adverse effects on the output or outcome of a particular process. Unusual variation is often identified and mitigated if not entirely eliminated in the process to improve the results of the process. The common causes or natural causes refer to the factors or elements that are required and are useful in ensuring positive outcomes in the process. Natural causes involve the working environment, machines used, materials employed, methods available, and the manpower operating the process. If all these factors are working perfectly then the process is well under statistic control, such factors are the natural or common causes.
Discussion 18-3
- How would you rate the comparative competitiveness of the two companies?
The comparative competitiveness of Companies ABC and XYZ can be rated according to their costs of manufacturing the desired products and their ability to produce goods at a low cost. XYZ has a higher comparative competitiveness than ABC Company since with it low production costs it can be able to offer its products in the market at low prices. The two companies can also be rated by the use of SPC in their production process; ABC does not use the SPC and thus it is weak in its comparative competitiveness as compared to XYZ. This shows the importance of SPC in the production and competition between the two companies. The comparative competitiveness of company ABC is lower than that of Company XYZ.
- If you work for a company that does not employ SPC, how could SPC help the firm?
SPC usage in the firm helps in various issues, and companies not using the SPC should adopt it for the benefit of the business and to improve their competitiveness. As indicated SPC would help, the firm lowers its production costs and, as a result, reduces the prices of its products. Lower prices of the company’s products would increase the sales and, therefore, the revenue generated by the firm. Furthermore, adoption of the SPC helps in improving the competitiveness of a company against similar companies in the industry. The use of SPC in the company would ensure predictable and consistent processes. SPC would help in eradicating any chance of defective products and improve the quality of the products offered by the company. The use of SPC in the company would call for increased commitment and standards from the management and the workers as it is always with improved quality, commitment and standards are beneficial to the firm. Its usage would also ensure continuous growth and development of the company.
