Data transformation
dplyr
Roland Krause
2021-09-09
Judgment
This short tutorial will allow you to explore dplyr functionality based on the previous lecture. Every question can be answered with a combination of %>% pipes. You should refrain from using temporary variables and statements outside of the range of the tidyverse.
Import the data from the website.
Assign to the name judgments
Use glimpse() to identify columns and column types.
Select all columns that refer to the STAI questionnaire
Select all subjects older than 25
Retrieve all subjects younger than 20 which are in the stress group
The column for the group is condition.
Abbreviate the gender column such that only the first character remains
Normalize the values in the REI group
Divide all entries in the REI questionnaire by 5, the maximal value.
Find the moral dilemma with the highest average score across all participants.
The result should be a tibble containing the dilemma and the average such that the dilemma with the highest average in the first row.
Genetic variants
Clean the table of genetic variants such that all variants appear as a column labeled by their position.
The format in the input is the reference allele, the position and the variant, commonly called alternative allele. In T6G, T is the reference allele, 6 is the position (along the gene) and G is the variant allele.
variants <- tribble(
~sampleid, ~var1, ~var2, ~var3,
"S1", "A3T", "T5G", "T6G",
"S2", "A3G", "T5G", NA,
"S3", "A3T", "T6C", "G10C",
"S4", "A3T", "T6C", "G10C"
)The table should look something like this.
| sampleid | 3 | 5 | 6 |
|---|---|---|---|
| S1 | T | G | G |
| S2 | G | G | NA |
Select relevant variants
Genetic variants are labeled acording to their effect on stability of the gene product.
Select the subjects in table variants that carry variants labeled as damaging.
The final output should be vector of sample ids.
variant_significance <- tribble(
~variant, ~significance,
"A3T", "unknown",
"A3G", "damaging",
"T5G", "benign",
"T6G", "damaging",
"T6C", "benign",
"G10C", "unknown"
)