Control Charts Operations Management for Managers Control

Control Charts

Operations Management for Managers

Control charts: Wal-Mart

How control charts might be used to monitor a process

"The control chart is a graph used to study how a process changes over time. Data are plotted in time order. A control chart always has a central line for the average, an upper line for the upper control limit and a lower line for the lower control limit" (Tauge 2004). Wal-Mart can use control charts, for example, to monitor the quality of a particular product produced by supplier, the efficiency of a supplier, the costs of procuring the same type of good from different suppliers, or even to engage in quality control of employees and managers by measuring the number of customer complaints at a particular facility.

Q2. How to possibly improve quality at specific levels from doing research on your organization?

Wal-Mart has been known to try to tightly control its suppliers: "Often companies browbeat their suppliers into providing goods at low costs. Wal-Mart has been known to be very tough on suppliers, even driving some out of business if they did not bend to Wal-Mart's demands. Other companies have also used such negative tactics" (Kurtus 2007). Through the use of quality monitoring, Wal-Mart can demonstrate to a supplier when quality has been slipping, based upon its plotted performance on a control chart. It can also attempt to improve customer service or efficiency of managers by setting goals which employees are supposed to meet.

Control charts are useful for their flexibility because they can monitor different types of processes. "Control charts come in two main types, variable charts that deal with variable data, that is data that will vary across a range of measurements such as temperature or length. The second type is Attribute Data, this is the data that we would normally record using a simple tally chart, so number of rejects would be controlled on an attribute chart" (Leanman 2011). Control charts can thus be used to track sales figures from season to season using variable charts, but also quality control, worker retention, and other discrete figures as attributes. Charting allows for easier comparison and more obvious tracking of anomalies or problems. Although Wal-Mart is a large organization, because of its determination to offer the lowest prices, such knowledge is essential. "At the very centre of the company's business model is a constant effort to drive down costs to an absolute minimum. Every pound, penny and tenth of a penny per unit of stock turns into millions in a firm of Wal-Mart's size. With the scale the company has, the economies of scale it can command, it basically extracts every last nickel out of its suppliers" (Clark 2010).

Q3. Any specific quality measures that your organization uses to compare itself against its competitors. What do these measures mean?