Ishikawa's Seven Basic Tools of Quality Control

Cause and Effect Diagrams
1. Identify underlying symptoms
  1. Find the root cause
2. Causes identified
  1. Brainstorm
    1. Working Backwards
Control or Shewhart Charts
1. Manufacturing or business process
  1. Statistical control or not?
    1. Stable
      1. Data used to predict future performance
    2. Not in control
      1. Data helps to find sources of variation
2. Allows significant change to be differentiated from natural process
3. Objective and discipline approach
Check Sheet
1. Collects data in real time
2. Quick, easy and efficient recording
3. Clasificación, Location, Frecuency, Measurement Scale, Check List
Histogram
1. Visual Impression of data distribution
2. Used to plot density of data
Pareto Chart
1. Highlights most importan set of factors
2. Represents most common source of defects
Scatter plot or graph
1. Displays values for two variables
2. Used when a variables is under control of the experimenter
3. Suggests various kinds of correlations
  1. Positive, negative or uncorrelated
4. Shows non linear relationships
Stratified Sampling
1. Sampling from population
2. Dividing members into homogenous subgroups
3. Strata
  1. Mutually exclusive
  2. Collectively exhaustive
  3. Random or systematically sampling
    1. Improves representativeness

Resource summary

	Created by raul.delolmo about 10 years ago