In my travels I have worked with all kinds of people. One thing I have noticed is that some have a different understanding of how to average. The problem usually arises when they try to average averaged numbers. What does this mean? Let me explain:
Average (or mean): is the result of adding all numbers together then dividing by the number of numbers.
To give an example: If a product received 100 ratings on a 5-star scale with an average of 3.8. This would mean that some would be 1’s, some would be 5’s but mostly would be 3 or 4.
The problem that I’ve seen is when categories or sub-categories factor in. If a product gets 100 reviews, but the product comes in 4 colours, 1 colour might get an average of 2 while another might get an average of 4. Some might try to average these together to get 3. However, if the 2 star product had 2 reviews and the 4 star product had 50 reviews, then the overall average would actually be closer to 4 than it would be to 3. This is the rule of weights and weighting, however, that’s for another day.