mssd {REAT} | R Documentation |
Calculating the mean square successive difference
mssd (x)
x |
a |
The mean square successive difference, \delta^2
, is a dimensionless measure of variability over time (von Neumann et al. 1941). It can be used for assessing the volatility of a variable with respect to different subjects/groups.
Single numeric value (the mean square successive difference, \delta^2
).
Thomas Wieland
Von Neumann, J./Kent, R. H./Bellinson, H. R./Hart, B. I. (1941): “The mean square successive difference”. In: The Annals of Mathematical Statistics, 12, 2, p. 153-162.
data1 <- c(10,10,10,20,20,20,30,30,30)
# stable growth
data2 <- c(20,10,30,10,30,20,30,20,10)
# high variability
# Means:
mean2(data1)
mean2(data2)
# Same means
# Standard deviation:
sd2(data1)
sd2(data2)
# Coefficient of variation:
cv(data1)
cv(data2)
# Measures of statistical dispersion are equal
mssd(data1)
mssd(data2)
# high differences in variability