Why it is necessary to summarise data. Explain the approaches available to summarize the data distributions?

Answer 1

Statistics For ManagementWhy it is necessary to summarise data? Explain the approaches available to summarize the data distributions?

Graphical representation is a good way to represent summarised data. However, graphs provide us only an overview and thus may not be used for further analysis. Hence, we use summary statistics like computing averages. to analyse the data. Mass data, which is collected, classified, tabulated and presented systematically, is analysed further to bring its size to a single representative figure. This single figure is the measure which can be found at central part of the range of all values. It is the one which represents the entire data set. Hence, this is called the measure of central tendency.

In other words, the tendency of data to cluster around a figure which is in central location is known as central tendency. Measure of central tendency or average of first order describes the concentration of large numbers around a particular value. It is a single value which represents all units.

Statistical Averages: The commonly used statistical averages are arithmetic mean, geometric mean, harmonic mean.

Arithmetic mean is defined as the sum of all values divided by number of values and is represented by X.

Before we study how to compute arithmetic mean, we have to be familiar with the terms such as discrete data, frequency and frequency distribution, which are used in this unit.

If the number of values is finite, then the data is said to be discrete data. The number of occurrences of each value of the data set is called frequency of that value. A systematic presentation of the values taken by variable together with corresponding frequencies is called a frequency distribution of the variable.

Median: Median of a set of values is the value which is the middle most value when they are arranged in the ascending order of magnitude. Median is denoted by 'M'.

Mode: Mode is the value which has the highest frequency and is denoted by Z.

Modal value is most useful for business people. for example, shoe and readymade garment manufactures will like to know the modal size of the people to plan their operations. for discrete data with or without freuency it is that value corresponding to highest frequency.