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1.13 Replacing Missing Data: Median Imputation Method (cont..)

1.13 Replacing Missing Data: Deriving Values Method

Looking at above image we see that we are remaining with values in column profit and expenses, which can be derived from other variables.
The formula is like this
Revenue = Expenses - Profit
Expenses = Revenue - Profit
Let's single out rows with missing values in column Profit
Very simple code, implemented as below
Let's check complete.cases().

We see only two rows with missing values and only one of them to be dealt with. It can be tackled using the same procedure.

 Let's check complete.cases() once again.

And there is only one row remaining now, which agreed to keep because it is not going to affect our calculation.
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