Test: Measures Of Central Tendency

Arithmetic mean is of two types:

• Simple arithmetic mean
• Weighted mean.

Deciles, as its name suggests, refers to the division of series into ten equal parts. The value of each part is known as deciles.

Measures of central tendency refers to all those methods of statistical analysis which are used to calculate the average of a set of data.

Median requires arrangement of data in either ascending or descending order before calculating median.

In case of classes like, below 10, 10-20, 20-30, 30-40, 40-50, above 50, computation of arithmetic mean would be impossible unless we assume the unknown limits.

► Standard deviation is the measure of how spread out the numbers of a data are.

► Mean is the average.

► Median is the middle number, when data is arranged in numerical order.

► Mode is the data item the appears most frequently.

Mean, median and mode are all measures of central tendencies.

► Mean is a mathematical average.

The arithmetic mean or mean is defined as the sum of values of a group of items divided by the number of items. It is denoted by mean.

In case of open end classes, computation of arithmetic mean would be difficult unless we assume the unknown limits.

Values that divide the series into hundred equal parts are called percentiles. In percentile, we get 99 dividing positions denoted by P₁, P₂,……..,P₉₉.