add installation spoiler + fix

Author: avallecam

episodes/modelling-interventions.Rmd

@@ -28,8 +28,24 @@ library(epidemics)
 Learners should also familiarise themselves with following concept dependencies before working through this tutorial: 
 
 **Outbreak response** : [Intervention types](https://www.cdc.gov/nonpharmaceutical-interventions/).
+
+**R packages installed**: `{epidemics}`, `{socialmixr}`, `{scales}`, `{tidyverse}`.
+
 :::::::::::::::::::::::::::::::::
 
+:::::::::: spoiler
+
+Install packages if their are not already installed
+
+```r
+if (!base::require("pak")) install.packages("pak")
+pak::pak(c("epiverse-trace/epidemics", "socialmixr", "scales", "tidyverse"))
+```
+
+If you have any error message,
+go to the [main setup page](../learners/setup.md#software-setup).
+
+::::::::::
 
 ## Introduction
 

episodes/simulating-transmission.Rmd

@@ -37,7 +37,7 @@ Learners should familiarise themselves with following concept dependencies befor
 
 **Epidemic theory** : [Transmission](https://doi.org/10.1155/2011/267049), [Reproduction number](https://doi.org/10.3201/eid2501.171901).
 
-**R packages installed**: `{epidemics}`, `{socialmixr}`, `{tidyverse}`.
+**R packages installed**: `{epidemics}`, `{socialmixr}`, `{scales}`, `{tidyverse}`.
 
 :::::::::::::::::::::::::::::::::