Codebook.md

Codebook for tidyMeans_wide

How the data was derived from source The data in tidyMeans_wide is based on provided data in "UCI HAR dataset.zip" Data was mutated in following manner (for details of transformations see README.md)

1. load and combine data from test and train-sets
2. subject and activity was linked to rows
3. columns without mean() of std() were removed from datatable leaving 66 measurements (plus 'subject' and 'activity', so 68 columns in total)
4. some labels were corrected
5. for each measurement mean was calculated per subject per activity This results in a wide format dataset with 68 columns and 180 rows: tidyMeans_wide as described below.

Two important remarks

1. Original test and train sets where normalized and bounded [-1,1] -> calculated means tidyMeans [-1,1]
2. The original dataset contains more columns with either mean or std in their variable names. I ONLY selected the 17 variables named in features_info.txt, 8 of those are three dimensional data, so 8*3 (single dimension + 9 = 33 with each mean() and std > 66 variables in the tidy dataset, plus 2 identifiers (subject and activity)

Data definition (column name - values = description) subject - integer [1..30] = unique identifier for the subject taking part in experiment
activity - factor [LAYING, SITTING, STANDING, WALKING, WALKING-DOWNSTAIRS, WALKING-UPSTAIRS] = activity type by subject tBodyAcc.mean...X - numeric [-1,1] = averaged mean body acceleration in X-axis ; time tBodyAcc.mean...Y - numeric [-1,1] = averaged mean body acceleration in Y-axis ; time tBodyAcc.mean...Z - numeric [-1,1] = averaged mean body acceleration in Z-axis ; time tBodyAcc.std...X - numeric [-1,1] = averaged std deviation body acceleration in X-axis ; time tBodyAcc.std...Y - numeric [-1,1] = averaged std deviation body acceleration in Y-axis ; time tBodyAcc.std...Z - numeric [-1,1] = averaged std deviation body acceleration in Z-axis ; time tGravityAcc.mean...X - numeric [-1,1] = averaged mean gravity acceleration in X-axis ; time tGravityAcc.mean...Y - numeric [-1,1] = averaged mean gravity acceleration in Y-axis ; time tGravityAcc.mean...Z - numeric [-1,1] = averaged mean gravity acceleration in Z-axis ; time tGravityAcc.std...X - numeric [-1,1] = averaged std deviation gravity acceleration in X-axis ; time tGravityAcc.std...Y - numeric [-1,1] = averaged std deviation gravity acceleration in Y-axis ; time tGravityAcc.std...Z - numeric [-1,1] = averaged std deviation gravity acceleration in Z-axis ; time tBodyAccJerk.mean...X - numeric [-1,1] = averaged mean Body Jerk acceleration in X-axis ; time tBodyAccJerk.mean...Y - numeric [-1,1] = averaged mean Body Jerk acceleration in Y-axis ; time tBodyAccJerk.mean...Z - numeric [-1,1] = averaged mean Body Jerk acceleration in Z-axis ; time tBodyAccJerk.std...X - numeric [-1,1] = averaged std dev Body Jerk acceleration in X-axis ; time tBodyAccJerk.std...Y - numeric [-1,1] = averaged std dev Body Jerk acceleration in Y-axis ; time tBodyAccJerk.std...Z - numeric [-1,1] = averaged std dev Body Jerk acceleration in Z-axis ; time tBodyGyro.mean...X - numeric [-1,1] = averaged mean Body Gyro in X-axis ; time tBodyGyro.mean...Y - numeric [-1,1] = averaged mean Body Gyro in Y-axis ; time tBodyGyro.mean...Z - numeric [-1,1] = averaged mean Body Gyro in Z-axis ; time tBodyGyro.std...X - numeric [-1,1] = averaged std dev Body Gyro in X-axis ; time tBodyGyro.std...Y - numeric [-1,1] = averaged std dev Body Gyro in Y-axis ; time tBodyGyro.std...Z - numeric [-1,1] = averaged std dev Body Gyro in Z-axis ; time tBodyGyroJerk.mean...X - numeric [-1,1] = averaged mean Body Gyro Jerk in X-axis ; time tBodyGyroJerk.mean...Y - numeric [-1,1] = averaged mean Body Gyro Jerk in Y-axis ; time tBodyGyroJerk.mean...Z - numeric [-1,1] = averaged mean Body Gyro Jerk in Z-axis ; time tBodyGyroJerk.std...X - numeric [-1,1] = averaged std dev Body Gyro Jerk in X-axis ; time tBodyGyroJerk.std...Y - numeric [-1,1] = averaged std dev Body Gyro Jerk in Y-axis ; time tBodyGyroJerk.std...Z - numeric [-1,1] = averaged std dev Body Gyro Jerk in Z-axis ; time tBodyAccMag.mean... - numeric [-1,1] = averaged mean Body acceleration Magnitude; euclidian norm from XYZ signals ; time tBodyAccMag.std... - numeric [-1,1] = averaged std dev Body acceleration Magnitude; euclidian XYZ ; time tGravityAccMag.mean... - numeric [-1,1] = averaged mean Gravity acceleration Magnitude; euclidian XYZ ; time tGravityAccMag.std... - numeric [-1,1] = averaged std dev Gravity acceleration Magnitude; euclidian XYZ ; time tBodyAccJerkMag.mean.. - numeric [-1,1] = averaged mean Body acceleration Jerk Magnitude; euclidian norm from XYZ signals ; time tBodyAccJerkMag.std.. - numeric [-1,1] = averaged std dev Body acceleration Jerk Magnitude; euclidian XYZ ; time tBodyGyroMag.mean.. - numeric [-1,1] = averaged mean Body Gyro Magnitude; euclidian XYZ ; time tBodyGyroMag.std.. - numeric [-1,1] = averaged std dev Body Gyro Magnitude; euclidian XYZ ; time tBodyGyroJerkMag.mean.. - numeric [-1,1] = averaged std dev Body Gyro Jerk Magnitude; euclidian XYZ ; time tBodyGyroJerkMag.std.. - numeric [-1,1] = averaged std dev Body Gyro Jerk Magnitude; euclidian XYZ ; time fBodyAcc.mean...X - numeric [-1,1] = averaged mean body acceleration in X-axis ; freq fBodyAcc.mean...Y - numeric [-1,1] = averaged mean body acceleration in Y-axis ; freq fBodyAcc.mean...Z - numeric [-1,1] = averaged mean body acceleration in Z-axis ; freq fBodyAcc.std...X - numeric [-1,1] = averaged std deviation body acceleration in X-axis ; freq fBodyAcc.std...Y - numeric [-1,1] = averaged std deviation body acceleration in Y-axis ; freq fBodyAcc.std...Z - numeric [-1,1] = averaged std deviation body acceleration in Z-axis ; freq fBodyAccJerk.mean...X - numeric [-1,1] = averaged mean Body Jerk acceleration in X-axis ; freq fBodyAccJerk.mean...Y - numeric [-1,1] = averaged mean Body Jerk acceleration in Y-axis ; freq fBodyAccJerk.mean...Z - numeric [-1,1] = averaged mean Body Jerk acceleration in Z-axis ; freq fBodyAccJerk.std...X - numeric [-1,1] = averaged std dev Body Jerk acceleration in X-axis ; freq fBodyAccJerk.std...Y - numeric [-1,1] = averaged std dev Body Jerk acceleration in Y-axis ; freq fBodyAccJerk.std...Z - numeric [-1,1] = averaged std dev Body Jerk acceleration in Z-axis ; freq fBodyGyro.mean...X - numeric [-1,1] = averaged mean Body Gyro in X-axis ; freq fBodyGyro.mean...Y - numeric [-1,1] = averaged mean Body Gyro in Y-axis ; freq fBodyGyro.mean...Z - numeric [-1,1] = averaged mean Body Gyro in Z-axis ; freq fBodyGyro.std...X - numeric [-1,1] = averaged std dev Body Gyro in X-axis ; freq fBodyGyro.std...Y - numeric [-1,1] = averaged std dev Body Gyro in Y-axis ; freq fBodyGyro.std...Z - numeric [-1,1] = averaged std dev Body Gyro in Z-axis ; freq fBodyAccMag.mean.. - numeric [-1,1] = averaged mean Body acceleration Magnitude; euclidian norm from XYZ signals ; freq fBodyAccMag.std.. - numeric [-1,1] = averaged std dev Body acceleration Magnitude; euclidian XYZ ; freq fBodyAccJerkMag.mean.. - numeric [-1,1] = averaged mean Body acceleration Jerk Magnitude; euclidian norm from XYZ signals ; freq fBodyAccJerkMag.std.. - numeric [-1,1] = averaged std dev Body acceleration Jerk Magnitude; euclidian XYZ ; freq fBodyGyroMag.mean.. - numeric [-1,1] = averaged mean Body Gyro Magnitude; euclidian XYZ ; freq fBodyGyroMag.std.. - numeric [-1,1] = averaged std dev Body Gyro Magnitude; euclidian XYZ ; freq fBodyGyroJerkMag.mean.. - numeric [-1,1] = averaged std dev Body Gyro Jerk Magnitude; euclidian XYZ ; freq fBodyGyroJerkMag.std.. - numeric [-1,1] = averaged std dev Body Gyro Jerk Magnitude; euclidian XYZ ; freq