I am developing a classification model for covid19 symptoms (after being ill) and I don't understand statistical analysis importance (some parts of it)
1 Firstly: Basically we perform statystical analysis to learn about data. However what's the purpose of counting mean, standard deviation as shown here:
https://www.sciencedirect.com/science/article/pii/S0010482522000762#bib27
What insight will it give me?
2 Moreover: They perform statistical test like Chi-Square to find the statistically significant features. Suppose they have around 15 "blood parameteres" and the tests would tell that only 10 of them are statistically important. Does it mean those 5 won't be used in the training and can be removed?
3 If they can be removed: Would feature elimination prove the same? Suppose we used Recursive Feature Elimination / Random forest with 10-best features. Would results be the same?