In week 4 study, we’ve learned about the clear definition of observational unit(level-1) and the grouping units(level-2), which we have to clarify them in a real experiments. Also, we learned about how to find out fixed effects, random effects, and mixed effects in a real case, in order to determine…

In week 3, we learned about confounding variables and study design. Confounding variable s a variable that will both affect the explanatory and response variable, which we have to be aware of when carrying out a study design, otherwise, an incorrect conclusion is very likely to be conducted. For…

In week 2, we learned about several useful packages in R, for example, ggplot2, dplyr, readr, sgringr, janitor, forcats, and tydyverse. Generally, these packages are very useful when doing data wrangling and data visualization. One of the important points in this week’s study is principle of tidy data, which has…

Stats Learning Week 1 In Week 1, we generally reviewed what we learned from linear regression model and the key assumptions of linear regression. Four assumptions should be satisfied before fitting a linear model: Linear relationship Errors are independent Errors are normally distributed Homoscedasticity The model are in the following…