Sometimes called the fishbone diagram, cause and effect analysis is Only about two-thirds of companies survive their first two years in business. It establishes what happened in relation to a certain business aspect. If an insurance company, for example, can underwrite policies faster or settle This is where cause-and-effect analysis, combined with careful design of the relationship between factors affecting a process and the output of that process. It is difficult if not impossible to solve complicated problems without considering many factors and the cause-and-effect relationships between those factors.
The company is trying to track down the causes for poor customer service and fix them. A simple cause-and-effect analysis could look something like Figure 1. Methods are the processes and procedures used by customer service to deliver its services. How annoying is it to wait on hold or be passed from person to person when calling for customer service? Does the customer reach the right person who can solve the problem, the very first time?
Call escalation — If the first customer service person cannot solve the problem, who does the customer talk to next? In the context of customer service, these are the policies, work environment, incentive and reward structures set up within the company for the customer service agents: In the context of customer service, these are the tools available to the agents to do their jobs: How good customer service is depends upon how well the CRM system is set up and fulfills the precise needs of the agents when providing service.
For customer service to be good, the agents must have certain skills: How does this relate to design of experiments? Good customer service depends to a large extent on the above factors, but how does a company decide that spending money on training is a more prudent investment than investing in a new CRM system? This is where DOE provides a way of measuring the relative efficacies of one cause over another.
Thus 80 percent of the improvement in customer service is likely to come from 20 percent of the causes above. The question is, which 20 percent? To address this question with an example DOE exercise, consider the quality of customer service provided as the dependent variable and the factors identified in the cause-and-effect analysis as the independent variables.
Decision-Making with Cause-and-Effect Analysis and DOE | iSixSigma
The experiments which could be done include the following: Now if the company can measure the quality of customer service in some objective way say, a comprehensive customer satisfaction surveythe company could compare the results of the experimental group with that of the control group to see the extent to which a training course improves agent performance. Their quality of service compared with the rest of the agents will give the company some idea of the real effects of the CRM system on agent performance.
Performing a process as a DOE exercise helps the company measure the results in as scientific a way as possible. This is a gross simplification of the kinds of information that DOE can provide. The above correlations of single factors as a determinant of quality of customer service can be analyzed using analysis of variance ANOVA to see how related quality of customer service is to any of the above factors.
One-way ANOVA relates one of the independent variables to the dependent variable — in this case, quality of customer service. Sometimes in practice, the combination of two factors is really worth more than just the two factors added up together. For example, experienced customer service managers know that good problem-solving skills, combined with a powerful knowledge base, can improve the quality of service dramatically.
Two-way ANOVA can help consider two factors together and analyze their effects on the quality of service on the whole, with proof obtained from data collected when processes are executed.
Machine A machine in software usually refers to the hardware, and there are a lot of possibilities that a problem can be due to the machine, such as performance issues. Other possible categories include policies, procedure, technology, and so on. After identifying a problem, the leader initiates a discussion with the project team to gather information about the possible causes, finally arriving at the root cause. The team can either analyze each of the above categories for possible causes or look into other categories not listed above.
Identify causes While brainstorming, the team should strive toward identifying major causes categories first, which can be further discussed, and then secondary causes for each major cause can be identified and discussed.
This helps the team to concentrate on one major cause at a time and to refine further for possible secondary causes. After the major causes usually four to six are identified, you can connect them as fishbones in the Fishbone diagram.
They are represented as slanted lines with the arrow pointing towards the backbone of the fish. See Figure 2 later in this article. Sometimes it is difficult to arrive at a few major causes. The team may come up with a lot of causes, which makes brainstorming more difficult. In this case, the leader can assign 10 points to each team member for each possible cause, and let them assign the rating from 1 to 10, 10 being most likely cause to each cause. After everyone on the team has rated the causes, the project manager totals each of the causes and ranks them based on their ratings.
From the list, the top four to six causes are identified as major causes and connected as bones in the diagram.
The diagram looks a little like the skeleton of a fish, hence the name Fishbone. After the major causes of the problem are identified, each one of them is discussed in further detail with the team to find out the secondary causes. If needed, the secondary causes are further discussed to obtain the next level of possible causes. Each of the major causes is laid as a fishbone in the diagram and the secondary causes as "bonelets.
However, the team has enough information to begin discussing the individual causes and to analyze their relevance to the problem.
The team can use analytical, statistical, and graphical tools to assist in evaluating each of the causes. The Pareto principle explained in part two of this article series is also used to find the elements that cause major problems and to list them as major causes in the Fishbone diagram. Software metrics that are obtained during application support can also be used here for further assistance.
Evaluate, decide, and take action It may be very difficult to come up with consensus on a large team for one possible root cause, but the majority is taken into consideration. Also, the major causes can be ranked in order with the most likely cause at the top of the list. After the evaluation process is complete, the action plan has to be decided.
If one possible root cause is identified, then the action plan has to be derived to rectify it. Sometimes, it may be difficult to arrive at the root cause; there may be a few possible root causes. In this case, the action plan has to be drawn for each of the possible root cause.
After the action plan is ready, the leader can designate an individual or team to work on the plan and to rectify the problem permanently. If there are a few possible root causes, all the action plans are to be executed, and the most likely root cause is identified and fixed. Example The Fishbone diagram can be used to troubleshoot Domino administration and Notes application-related problems.
Some complicated administration issues, such as SMTP mail routing, replication, server crashes, and so on, and application issues, such as database replication, can be better studied and analyzed using Fishbone diagrams. Let's look at how to apply the Fishbone technique to find the root cause of a Domino server crash. The idea in this example is to explain how to apply the Fishbone technique rather than how to identify the cause of the crash because a crash may happen for a number of reasons.
Define the problem In this example, the problem is already defined--Domino server crash. The team knows that the crash occurred because the server ran out of resources, but an analysis is still needed to determine why the resources are running low.
The leader starts drawing the Fishbone diagram by mentioning the problem in the fish head as shown below. The time of crash, frequency of crash, and crash details are all gathered prior to the brainstorming session. Brainstorm The team now is involved in the brainstorming session to identify the root cause of the problem.
We used the categories listed above as our starting point of discussion to identify the major causes first. We analyzed each category and their relevance to the problem. The following lists each of categories that figured in our discussion and whether it was accepted as a major cause.
Method The method or way of doing things was considered by the team as a possible cause. Because programs written for the Domino environment using formulas, LotusScript, Java, and so on may cause server overload and therefore a crashit was considered a major possible cause.
Men The team discussed the possibility of people being the cause of the problem. It is accepted as a major cause because a few less experienced administrators handled the mail and application servers.
Inexperience, negligence, and complacency are some reasons for mistakes that can eventually lead to a server crash. Management The project management team was not a possible cause because the issue here is more technical rather than managerial. The team unanimously ignored this category.
Material The team also ignored this category because material is not relevant to the problem. Machine The team discussed the machine being a possible cause.
Applying the Fishbone diagram and Pareto principle to Domino
Insufficient hardware configuration may be a problem leading to overloading and finally to server breakdown. The team accepted it as a major possible cause. Technology The team discussed the impact of the technology that has been used. Issues like anti-virus software, third-party tools, and software problem reports on the current Domino releases were pointed out, so technology was also identified as a possible cause.
Procedure The team discussed the various procedures used within the Domino environment. Procedures used in user registration, application roll-out, and migration were analyzed.
Decision-Making with Cause-and-Effect Analysis and DOE
The team decided that procedure could not be a possible cause. The team thought that if procedure was the reason, then the server might have crashed while executing the procedures. Policy The team discussed various policies used in the organization for the Domino environment.
Policies are quite specific to every organization, so a problem in an organization due to policy is not applicable to other organizations. Policies like scheduled agents, their schedules, servers, and APIs are studied as potential causes.
We considered policy as a major cause.