14.Types of Data Classifications:
Data can be classified by one, two or more characteristics at a time:
(i) One-way: when data are classified by one characteristic.
(ii) Two-way: when data are classified by two characteristics.
(iii) Three-way: when data are classified by three characteristics.
(iv) Many-way: when data are classified by many characteristics.
(i) Two-fold or dichotomy: we may divide a characteristic into two sub-classes one possessing the characteristic and the other not possessing it. For example, the literacy and illiteracy of a country.
(ii) Three-fold or trichotomy: when data are classified into three sub classes.
(iii) Manifold: when data are classified into many sub-divisions.