What is root cause analysis? How to identify a cause vs. a correlation? Give examples

What is root cause analysis? How to identify a cause vs. a correlation? Give examples



Root cause analysis:


- Method of problem solving used for identifying the root causes or faults of a problem
- A factor is considered a root cause if removal of it prevents the final undesirable event from recurring

Identify a cause vs. a correlation:
- Correlation: statistical measure that describes the size and direction of a relationship between two or more variables. A correlation between two variables doesn't imply that the change in one variable is the cause of the change in the values of the other variable
- Causation: indicates that one event is the result of the occurrence of the other event; there is a causal relationship between the two events
- Differences between the two types of relationships are easy to identify, but establishing a cause and effect is difficult

Example: sleeping with one's shoes on is strongly correlated with waking up with a headache. Correlation-implies-causation fallacy: therefore, sleeping with one's shoes causes headache.
More plausible explanation: both are caused by a third factor: going to bed drunk.

Identify a cause Vs a correlation: use of a controlled study
- In medical research, one group may receive a placebo (control) while the other receives a treatment If the two groups have noticeably different outcomes, the different experiences may have caused the different outcomes

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