Advantages of Z
scores:
One major advantage of standard or z scores is that they can
be used to compare raw scores that are taken from different tests especially
when the data are at the interval of management.
The
advantage of the z score transformation is that it takes into account both the
mean value and the variability in a set of raw scores
Disadvantages of Z
scores:
The main disadvantage
of standard scores is that they always assume a normal distribution. But if this
assumption is not met, the scores cannot be interpreted as a standard
proportion of the distribution from which they were calculated. For example, if
the distribution is skewed, the area with the standard deviation of 1 to the
left of the mean is not equal to the area within the same distance to the right
of the mean.
Conclusion:
Considering the foregoing, it was concluded that
Standard Scores are critical requirement for research into problems dealing
with data analysis in educational management. This is evident in the fact that
standard or z scores can be used to compare raw scores that are taken from
different tests especially when the data are at the interval level of
measurement.