This document contains an explanation of the variable column names, as well as a full list of all the variables in the tidyData.txt file.
subject - Each row identifies the subject who performed the activity for each window sample. Its range is from 1 to 30.
activity - Each row identifies the activity that was performed. Possible values are: WALKING, WALKING_UPSTAIRS, WALKING_DOWNSTAIRS, SITTING, STANDING, LAYING
Besides the subject and activity variables, the column names for all other variables have "subjectMean:" pre-pended in their name. This indicates that the data in these columns represent the by subject and activity for the given variable (a requirement of the assignment).
Bolded Examples:
subjectMean: fBodyAccJerkMean
subjectMean: tBodyGyroStdZ
After this prefix, the next part of the column name indicates the name of the signal that was used to estimte the variable for the original raw data set. In other words, the type of measurement.
Bolded Examples:
subjectMean: fBodyAccJerkStdX
subjectMean: fBodyAccJerkMeanY
Next, you will see in the column name either the word "Mean" or "Std". This indicates whether or not the column represents the mean or standard that was provided in the original raw data. This assignment required that we only include mean and standard deviation data, so those are the only two possible values.
Bolded Examples:
subjectMean: fBodyAccJerkStdX
subjectMean: fBodyAccJerkMeanY
Finally, some of the variable colmumns will have a letter X, Y, or Z at the very end. This indicate which of the 3-axial signals this variable represents.
Bolded Examples:
subjectMean: fBodyAccJerkStdX
subjectMean: fBodyAccJerkMeanY
For more information on how the data within each variable was collected, please consult the README file of the original data set, available at this URL: https://d396qusza40orc.cloudfront.net/getdata%2Fprojectfiles%2FUCI%20HAR%20Dataset.zip
subject - int
activity - factor
subjectMean: tBodyAccMeanX - normalized number
subjectMean: tBodyAccMeanY - normalized number
subjectMean: tBodyAccMeanZ - normalized number
subjectMean: tGravityAccMeanX - normalized number
subjectMean: tGravityAccMeanY - normalized number
subjectMean: tGravityAccMeanZ - normalized number
subjectMean: tBodyAccJerkMeanX - normalized number
subjectMean: tBodyAccJerkMeanY - normalized number
subjectMean: tBodyAccJerkMeanZ - normalized number
subjectMean: tBodyGyroMeanX - normalized number
subjectMean: tBodyGyroMeanY - normalized number
subjectMean: tBodyGyroMeanZ - normalized number
subjectMean: tBodyGyroJerkMeanX - normalized number
subjectMean: tBodyGyroJerkMeanY - normalized number
subjectMean: tBodyGyroJerkMeanZ - normalized number
subjectMean: tBodyAccMagMean - normalized number
subjectMean: tGravityAccMagMean - normalized number
subjectMean: tBodyAccJerkMagMean - normalized number
subjectMean: tBodyGyroMagMean - normalized number
subjectMean: tBodyGyroJerkMagMean - normalized number
subjectMean: fBodyAccMeanX - normalized number
subjectMean: fBodyAccMeanY - normalized number
subjectMean: fBodyAccMeanZ - normalized number
subjectMean: fBodyAccJerkMeanX - normalized number
subjectMean: fBodyAccJerkMeanY - normalized number
subjectMean: fBodyAccJerkMeanZ - normalized number
subjectMean: fBodyGyroMeanX - normalized number
subjectMean: fBodyGyroMeanY - normalized number
subjectMean: fBodyGyroMeanZ - normalized number
subjectMean: fBodyAccMagMean - normalized number
subjectMean: fBodyBodyAccJerkMagMean - normalized number
subjectMean: fBodyBodyGyroMagMean - normalized number
subjectMean: fBodyBodyGyroJerkMagMean - normalized number
subjectMean: tBodyAccStdX - normalized number
subjectMean: tBodyAccStdY - normalized number
subjectMean: tBodyAccStdZ - normalized number
subjectMean: tGravityAccStdX - normalized number
subjectMean: tGravityAccStdY - normalized number
subjectMean: tGravityAccStdZ - normalized number
subjectMean: tBodyAccJerkStdX - normalized number
subjectMean: tBodyAccJerkStdY - normalized number
subjectMean: tBodyAccJerkStdZ - normalized number
subjectMean: tBodyGyroStdX - normalized number
subjectMean: tBodyGyroStdY - normalized number
subjectMean: tBodyGyroStdZ - normalized number
subjectMean: tBodyGyroJerkStdX - normalized number
subjectMean: tBodyGyroJerkStdY - normalized number
subjectMean: tBodyGyroJerkStdZ - normalized number
subjectMean: tBodyAccMagStd - normalized number
subjectMean: tGravityAccMagStd - normalized number
subjectMean: tBodyAccJerkMagStd - normalized number
subjectMean: tBodyGyroMagStd - normalized number
subjectMean: tBodyGyroJerkMagStd - normalized number
subjectMean: fBodyAccStdX - normalized number
subjectMean: fBodyAccStdY - normalized number
subjectMean: fBodyAccStdZ - normalized number
subjectMean: fBodyAccJerkStdX - normalized number
subjectMean: fBodyAccJerkStdY - normalized number
subjectMean: fBodyAccJerkStdZ - normalized number
subjectMean: fBodyGyroStdX - normalized number
subjectMean: fBodyGyroStdY - normalized number
subjectMean: fBodyGyroStdZ - normalized number
subjectMean: fBodyAccMagStd - normalized number
subjectMean: fBodyBodyAccJerkMagStd - normalized number
subjectMean: fBodyBodyGyroMagStd - normalized number
subjectMean: fBodyBodyGyroJerkMagStd - normalized number