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Lesson code

Please download the zip folder below to code along with the instructor.

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Lesson notes

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Very good presentation! 😊


Hello everyone. I would ask a clarification about my code. I have met challenges when I want to execute the code related on pratice 1 and pratice 5. Code pratice 1 : {r eval = FALSE} # Enter your answer as a WHOLE number without quotes: Q_age_group_percentage <-   flu_linelist %>%   mutate(age_group = case_when(age… Read more »


Hi Axel, for the first question, you are assigning the entire table to the object “Q_age_group_percentage”. You should generate the table by itself, and then assign only the desired number to the object. For example, if your answer is 61, then you can put “Q_age_group_percentage <- 61″


Dear Joy, your answer isn’t clear. can you explain more on it?


Hi Joy/Axel, for me this does not work either. It might have to do with the tabyl output, which actually is in the unit proportion, not unit percentage.


Hi Edgar! Thank you for your message. I believe what Joy meant to say is that you SHOULDN’T assign the tabyl() table to the object “Q_age_group_percentage”. Instead, what we recommend you to do is to execute the code to see the table created with tabyl() AND THEN assign the correct value in percentage… Read more »


For practice question 5, you’re quite close to the correct answer. It looks like you are missing the word “to” in “Recruit to Jiangsu study” and “Recruit to Zhejiang study”. If you fix those two text strings, you should get the correct answer.


for this,it’s ok. I have modified it. Thank you.


Thank you for the lesson

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