- Variables data offers a richness not offered by attribute data. Thus, it is often advantageous to
transform attribute data to variables data.
- If the average count is large (> 20), treat the count as variables (continuous) data.
- Perform transformation on either c or p to convert to variables data.
- Test normality to verify a valid transformation. Must also have 5+ values in the distribution.
- If not valid, continue attribute assessment. If valid, treat the data as variables data.
In the Analyze phase, it is important to use
tools and methods in the proper sequence. For
example, graphical tools should always be used
before statistical tools. Likewise, testing for
normality and stability should always be done
before hypothesis testing. This guide provides a
general sequence in terms of tool usage during
the analysis of data.