1. The control chart is used to graphically display the measured data of an important product or process parameter. The diameter of bearing balls can be used as an example in manufacturing. In the service industry, the measured value can be whether the information required by an insurance claim is listed or not.
according to the statistical sampling steps, measure at different times. The control chart shows the measurement results changing with time, which is designed according to normal distribution, that is, the classic bell curve. It is easy to see whether the actual measured value falls within the statistical boundary of this distribution with the control chart.
2. pareto chart, also called Pareto Diagram, is a simple chart tool, which is used to count and display the number of various types of defects or problems in a certain period of time. The results are represented by bars with different lengths on the graph.
It is based on the research of 19th century Italian economist Wilfred pareto, that is, 21% of all possible causes cause about 81% of the problems; The remaining 81% causes only 21% problems and defects.
3. Fishbone diagram is also called causal analysis diagram or Ishikawa diagram. It looks a bit like a fish bone, and the problems or defects are marked outside the "fish head". Fish bones grow on fish bones, and the possible causes of production problems are listed according to the number of opportunities.
Fishbone diagram helps to explain how the causes interact with each other. It can also show how various possible causes appear in turn over time. This helps to solve the problem.
4. Trend chart is sometimes called trend chart. It is used to display the measurement results obtained in a certain time interval. Draw a graph with the measured quantity as the vertical axis and time as the horizontal axis.
the trend chart is like a constantly changing scoreboard. Its main purpose is to determine whether there are important time patterns in various types of problems. So that we can investigate the reasons.
5. Histogram is also called line graph. On the histogram, the number of products in the first control category is represented by the line length. The first category is marked, and the lines are arranged horizontally or vertically. Histograms can indicate which categories represent the majority of the measurements. It also shows the relative size of the first category.
6. The distribution chart provides a standard method to show how one variable is related to another. For example, to know the relationship between the tensile strength of a metal wire and the diameter of the wire, it is generally to stretch the wire until it breaks, and write down the exact value of the force used to break the wire. Plot the results with diameter as the horizontal axis and force as the vertical axis.
7. Flowcharts are sometimes called input-output charts. The diagram intuitively describes the specific steps of a working process. Flowchart is very helpful to know exactly how things are going and to decide how to improve the process. This method can be used in the whole enterprise, so as to intuitively track and illustrate the operation mode of the enterprise.
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