Compute the sample SD of binary data (i.e., only 0 and 1 values) in either of four ways, each based on different inputs:
sd_binary_groups()takes the cell sizes of both groups, those coded as 0 and those coded as 1.sd_binary_0_n()takes the cell size of the group coded as 0 and the total sample size.sd_binary_1_n()takes the cell size of the group coded as 1 and the total sample size.sd_binary_mean_n()takes the mean and the total sample size.
These functions are used as helpers inside debit(), and consequently
debit_map().
Usage
sd_binary_groups(group_0, group_1)
sd_binary_0_n(group_0, n)
sd_binary_1_n(group_1, n)
sd_binary_mean_n(mean, n)Arguments
- group_0
Integer. Cell size of the group coded as 0.
- group_1
Integer. Cell size of the group coded as 1.
- n
Integer. Total sample size.
- mean
Numeric. Mean of the binary data.
References
Heathers, James A. J., and Brown, Nicholas J. L. 2019. DEBIT: A Simple Consistency Test For Binary Data. https://osf.io/5vb3u/.
See also
is_subset_of_vals(x, 0, 1) checks whether x (a list or atomic
vector) contains nothing but binary numbers.
Examples
# If 127 values are coded as 0 and 153 as 1...
sd_binary_groups(group_0 = 127, group_1 = 153)
#> [1] 0.4987311
# ...so that n = 280:
sd_binary_0_n(group_0 = 127, n = 280)
#> [1] 0.4987311
sd_binary_1_n(group_1 = 153, n = 280)
#> [1] 0.4987311
# If only the mean and total sample size are
# given, or these are more convenient to use,
# they still lead to the same result as above
# if the mean is given with a sufficiently
# large number of decimal places:
sd_binary_mean_n(mean = 0.5464286, n = 280)
#> [1] 0.4987311