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--- a/journal/logbook.md
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@@ -1,5 +1,7 @@
 # MOOC Reproducible Research: my logbook
 
+# Mission 1
+
 ## Module 1: Cahier de notes, cahier de laboratoire
 
 I have started this module on June 5.
@@ -45,7 +47,7 @@ and completed several quizzes relsted to th each thematique of this Module.
 - How to use GitLab history
 - beginnig of the work with Jupyter notebook and commited it
 
-# Mission 2 - Module 2.
+# Mission 3 - Module 2.
 
 ## Excercice 02 (1st part)
 
@@ -90,3 +92,30 @@ Prior to the launch, a teleconference was held to assess the risk of taking off
     2. **Key data points were excluded** from the analysis.
     3. **the uncertainity of the logistic regression estimates was not taken into accounts**, leading to overconfidence in the predictions.
 
+# Mission 4 - Module 3
+
+## Exercise 03 (1st part)
+
+In this task, the following steps were perfomed:
+
+- The small part of code was implemented and modified to check whether the local CSV file already exists.
+- If the file does not exist, it is downloaded from the Réseau Sentinelles server and saved localy.
+- If the file is present, the local copy was used instead of re-downloading the data.
+- Necessary comments were added in the code to explain the logic and purpose of each step:
+    
+    - Firstly, check if the local CSV file already exists.
+    - Secondly, if the file does not exist, download it from the official URL and save it locally.
+    - Thirdly,this ensures that the analysis uses a consistent local copy and avoids repeated downloads.
+
+**A comparative analysis with the reference solution confirmed the implementation was correct.**
+
+## Exercise 03 (2nd part)
+
+The objective of this tast is to analyze the incidence of chickenpox using a new dataset. It is necessary to identify the strongest and weakest epidemic years using the incidence data.
+
+For this aim, I perfomed the following step:
+
+- Loaded the dataset from the Website Sentinelles 
+- Converted weekly data to dates and grouped it by epidemiological year (from September 1 to August 31)
+- Calculated the total incidence per epidemiological year
+