Merits and Limitations of Concurrent Deviation Method

Merits

1. It is the simplest of all the methods.

2. When the number of items is very large, this method may be used to form a quick idea
about the degree of relationship before making use of more complicated methods.

Limitations.

1. This method does not differentiate between small and big changes. For example, if X increases from 100 to 101 the sign will be plus and if Y increases from 60 to 160 the sign will be plus. Thus both get equal weight when vary in the same direction.

2. The results obtained by this method are only a rough indicator of the presence or absence of  correlation.