valid {ddp} | R Documentation |
This function calculates the item-rest correlation.
valid(data, alpha = 0.05, total = NULL)
data |
A data set/ matrix (see Details). |
alpha |
An alpha value (see Details). |
total |
A single numeric value of the index column (see Details). |
The data set is a data frame/ matrix n x k. The row is
the name of the respondent as many as n, while the column is
the variables (k). The alpha value is set between 0.0001 and
0.20, the default is 0.05. If the total
input is NULL
,
it means that the total score will be calculated first,
the column index of the total score can be also stated otherwise.
The index of the column is a numeric value with a length of one.
It has to be between 1 and (k).
Function returns a data frame with k row and four columns. the columns indicate the item-rest correlation, correlation threshold, p value, and validity and reliability conclusion.
Weksi Budiaji
Contact: budiaji@untirta.ac.id
#data simulation of 10 person 5 variables
set.seed(1)
dat <- matrix(sample(1:7,10*5, replace = TRUE), 10,5)
valid(dat)