That makes sense. Thanks.Its not that I have noticed anything wrong (although as I say I haven't read it all), it's just the way the material is presented - for instance "[the] Median is used over the mean since it is more robust to outlier values". When is the median used in preference over the mean? What even is the mean? Or the median (it is explained as "the line in the middle!")? What does the symbol "IQR" on the chart mean (it is "inter-quartile range of course, and the author talks about the box-plot being "short" or "tall" (in relation to what?) without referring to this label). And then the wonderful tautology I have already quoted - "the first quartile is essentially the 25th percentile". If I don't know what a quartile is how on Earth am I going to know what a percentile is?
When I am looking for an introductory or refresher text, a key indicator is how well it explains the things I already know. If it does a good job, I am inclined to trust the author to explain new material. If it doesn't, then I turn elsewhere.
This doesn't explain anything about Poisson distribution. And no single mention that it is a discrete distribution comparing to Normal, which is continuous.A Poisson Distribution is similar to the Normal but with an added factor of skewness.
After rereading it, I agree. It seems like "here are some things to go learn more about."Having just very quick view on the article, I found it quite vague. For example:
This doesn't explain anything about Poisson....