Improvements to tutorial 5 and 6

Problem tutorial 5

[ ] Clarify what correlation metric you are using (Spearman, Pearson, etc. and why)
[ ] Wrong statement: Negative does not mean that they is no correlation. Negative means they are is a NEGATIVE correlation. can actually also be a predictor. Important: Significant values need to be mentioned.
[ ] Tutorial should be a simple regression first and then a lagged regression
[ ] Make sure during a training we actually RUN the cells
[ ] Explain what a linear regression is: What is the estimator used to fit the data?
[ ] Better explain why we use a lag of one and not more or less!
[ ] Missing: Splitting in test and training set, and then apply it to a make a prediction for a week that you do not have!
[ ] Include theories for lag regression and linear regression

Problem tutorial 6

[x] Remove section on adding "comments". We actually do not want to have comments!
[x] comma separate

ironhacks / Tutorials-COVID-19