Continuous series means where frequencies are given along with the value of the variable in the form of class intervals. For example. Here: (i) 10-20, 20-30 ... etc. are class intervals. (ii) 3, 7, 11, 9, 6 is known as their respective frequencies. (iii) In 20-30, 30-40.... etc. 20 is the lower and 30 the upper limit of 20-30 class [...]
Individual Series: Individual series means where frequencies are not given. Here the mean can be found by three methods. (i) Direct Method: Example 1. Find Mean for the following figures. Solution: ∑X =30 + 41 + 47 + 54 + 23 + 34 + 37 + 51 + 53 + 47=417; N= 10. (ii) Short Cut Method: Here X is [...]
(A) Merits: 1. It can be easily calculated; and can be easily understood. It is the reason that it is the most used measure of central tendency. 2. As every item is taken in calculation, it is effected by every item. 3. As the mathematical formula is rigid one, therefore the result remains the same. 4. Fluctuations are minimum for [...]