As a by-product of open-sourcing (and refactoring) my site, I have improved the bacteria details page by adding a table on core statistics as shown below. For this example I picked Bifidobacterium since that it a concern for many people and also illustrated some problems using averages.

For the computer nerds, you may wish to examine the open source post (with source code).

The first shock (to many of you) may be that the average was 17,800. WAIT – 50% of the people are only at 5413. In fact, only the highest 25% will have values at or above the average. If we do the usual 2 standard deviation for ‘normal range’ using these statistics, our range is 0 – 94,000. Thus people with zero bifidobacterium are in the normal range!.

Bottom Line

The numbers are there, you may need to acquire some knowledge about interpreting these numbers. You also need to stop thinking of bacteria behaving like a bell-curve/normal distribution.

• Mean
• Median
• Mode
• Minimum
• Maximum
• Standard Deviation
• Variance
• Skewness
• Kurtosis