valid.days {accelmissing}

Select the Valid Days

Description

Selects the complete (valid) days that include sufficient wearing time.

Usage

valid.days(PA, label, flag, wear.hr = 10, time.range = c("09:00", "20:59"), 
mark.missing = 0)

Arguments

PA

an N by T matrix including activity counts, where N is the total number of daily profiles, and T is the total minutes of a day (T=1440).

label

an N by 2 matrix including the labels corresponding to PA matrix. The first column, label[,1], includes the person id, and the second column, label[,2], includes the day label of 1 to 7, indicating Sunday to Saturday.

flag

an N by T matrix with the values of either 1 or 0 which indicating wearing or missing. This matrix can be created from create.flag().

wear.hr

Minimum wearing hours during the time range. If wear.hr=10 (default), select the valid days that include more than 10 hours of wearing.

time.range

Define the time range for the standard measurment day. Default is time.range = c("09:00", "20:59").

mark.missing

If mark.missing = 0 (default), the nonwearing time is marked by 0 while the wearing time is marked by 1 in flag matrix. If mark.missing = 1, it is the opposite.

Value

List with the updated PA, label and flag matrix objects.

Author(s)

Jung Ae Lee <[e-mail]>

References

[1] Lee JA, Gill J (2016). Missing value imputation for physical activity data measured by accelerometer. Statistical Methods in Medical Research.

See Also

valid.subjects

Examples

data(acceldata); attach(acceldata) # read data
	
# filtering data for valid days
valid.days.out = valid.days(PA, label, flag, wear.hr=8,  time.range=c("09:00","20:59"))
ls(valid.days.out)