Problem-Solving Methodologies

3: What are causes of the big problems?

 Once it is known what the biggest problem is, there will be a need to determine what needs to be done to eliminate it. The problem may be due to numerous things (e.g., raw materials, equipment, poor or no training, unclear procedures, the inability to measure accurately and precisely something, or variability in temperature or humidity). It is best to use the Ishikawa Diagram to answer this question. Sometimes this tool is called a fishbone, feather, or cause and effect (C & E) diagram. The branches on the diagram graphically display the major factors and sub factors relating to the problem. Historically, the major causes were referred to as the four M’s, man, machine, methods, and materials. In the early 1980s, man was appropriately replaced with persons or people. I have found it beneficial to add a branch to the diagram for environment. With this tool, often using brainstorming techniques, we probe the relationship of possible causes of our problem.

4: What does a look at the past data show us?

 After one select a probable cause to the problem, there will be a need to examine historical data for analysis. For this it is preferable to use the Histogram to answer such a question. Knowing different kinds of data (measurable, count, proportional, etc.) form particular shapes or frequency distributions is a great help. The histogram enables one to determine whether the data fits the theory for developing a solution and whether some unusual, unexpected, and/or undesirable behavior is present that should be eliminated. For example, if our data are measurable (inches, pounds, feet, etc.), then the expectation is for the bell-shaped “normal” distribution. However, if a Poisson shape should be seen, then the process must stop, and a determination made as to why the shape is not what was anticipated. Unexpected shapes are often the result of unknowingly using nonhomogeneous data, such as multiple machines or shifts, unfit or outdated parts from different machines or suppliers. The histogram reduces the chance of making an error in the subsequent steps of our analysis.

5: Is the hypothesized cause and effect relationship real?

 Astute time management skills are needed if control is to establish whether changes to a selected “cause” will create an impact on the effect/action one will want to change, improve, or eliminate. For this, the tool one can use to answer this question is the scatter diagram. When one concludes a relationship does not exist, then there will be a need to go back to Step 3 (Question 3) and select the next most likely cause.

6: What does the current data show us about this activity?

 The Control Chart can be used to answer this question. The control chart provides a means to monitor an activity (process) while it is running. This tool can alert us to abnormalities (changes) and outliners in the process so corrective actions can be taken before they become chronic problems. These abnormalities might be due violations of procedures or failure to ensure the integrity of adjustments a person or machine made through changes in materials, manufacturing process or changes in people, such as a shift change. As a preventive tool, it also tells us when things are running the best according to specifications/expectations. Therefore, the control chart demonstrates when to do plan an activity, and when to leave such activity as is.

The incomparable Dr. W. Edwards Deming (1985) once said, “If we go about it right solving problems may be easier than we think.” These questions are aimed to establish thinking processes using statistical methodologies and techniques to take mitigate problems before they happen.