**Statistics for Economics for Class 11 Chapter 4 Presentation of Data**

1. **Bar Diagram **– The pictorial representation of grouped data, in the form of vertical or horizontal rectangular bars, where the lengths of the bars are equivalent to the measure of data, are known as bar graphs, bar diagrams, or bar charts.

The bars drawn are of uniform width, and the variable quantity is represented on one of the axes. Also, the measure of the variable is depicted on the other axes. The heights or the lengths of the bars denote the value of the variable, and these graphs are also used to compare certain quantities. The frequency distribution tables can be easily represented using bar charts which simplify the calculations and understanding of data.

2. **Simple Bar Diagram** – A simple bar diagram is used to illustrate the data having only one variable that is classified on a temporal, quantitative, or spatial basis. In a simple bar diagram, one makes the bars with equal widths with varying lengths, that is, the vastness of a quantity portrayed by the length or height of the bars.

3.** Multiple Bar Diagram **– In a multiple bar diagram, different components are shown in different bars, and not more than three items can be shown comfortably. It can be used to compare the relative importance of different components.

In other words, a bar diagram is used to represent just one set of data. Therefore, when there are two or more sets of data that need to be represented and compared on the same graph, a multiple bar diagram or component bar diagram is used.

4. **Component Bar Diagram** – Component bar diagrams are also called sub diagrams that represent different components of a single piece of data. A pie chart is also used to represent a similar distribution of data, but it is a circular diagram, unlike a component bar diagram which is rectangular.

In other words, subdivided bar diagrams are those diagrams that simultaneously present total values as well as part values of a set of data. Different parts of a bar must be shown in the same order for all bars of a diagram.

5. **Pie Diagram or Pie Chart** – The “pie chart” is also known as a “circle chart”, dividing the circular statistical graphic into sectors or sections to illustrate the numerical problems. Each sector denotes a proportionate part of the whole. To find out the composition of something, Pie-chart works the best at that time. In most cases, pie charts replace other graphs like bar graphs, line plots, histograms, etc.

6. **Histogram** – A histogram is a graphical representation of a grouped frequency distribution with continuous classes. It is an area diagram and can be defined as a set of rectangles with bases along with the intervals between class boundaries and with areas proportional to frequencies in the corresponding classes. In such representations, all the rectangles are adjacent since the base covers the intervals between class boundaries. The heights of rectangles are proportional to corresponding frequencies of similar classes, and for different classes, the heights will be proportional to corresponding frequency densities.

In other words, a histogram is a diagram involving rectangles whose area is proportional to the frequency of a variable, and the width is equal to the class interval.

7. **Frequency Polygon** – A frequency polygon is almost identical to a histogram, which is used to compare sets of data or to display a cumulative frequency distribution. It uses a line graph to represent quantitative data. Frequency polygons are a visually substantial method of representing quantitative data and its frequencies.

8.** Mode** – In statistics, the mode is the value that is repeatedly occurring in a given set. We can also say that the value or number in a data set, which has a high frequency or appears more frequently, is called mode or modal value. It is one of the three measures of central tendency, apart from mean and median. For example, the mode of the set {3, 7, 8, 8, 9} is 8. Therefore, for a finite number of observations, we can easily find the mode. A set of values may have one mode or more than one mode, or no mode at all.

9. **Ogive** – The ogive is defined as the frequency distribution graph of a series. The ogive is a graph of a cumulative distribution, which explains data values on the horizontal plane axis and either the cumulative relative frequencies, the cumulative frequencies, or cumulative percent frequencies on the vertical axis.

Cumulative frequency is defined as the sum of all the previous frequencies up to the current point. To find the popularity of the given data or the likelihood of the data that fall within a certain frequency range, the ogive curve helps in finding those details accurately.

10. **Median** – The median of a set of data is the middlemost number or centre value in the set. The median is also the number that is halfway into the set.

To find the median, the data should be arranged, first, in order of least to greatest or greatest to the least value. A median is a number that is separated by the higher half of a data sample, a population, or a probability distribution, from the lower half. The median is different for different types of distribution.

For example, the median of 3, 3, 5, 9, and 11 is 5. If there is an even number of observations, then there is no single middle value; the median is then usually defined to be the mean of the two middle values: so the median of 3, 5, 7, 9 is (5+7)/2 = 6.

11. **Arithmetic Line Graph** – A graph showing arithmetic values of a variable is called an ‘Arithmetic-line graph’. Often such graphs are constructed to present time series data, that is, the data corresponding to different weeks, months, or years. Therefore, arithmetic-line graphs are often called ‘time series graphs’.

We hope that the offered Statistics for Economics Index Terms for Class 11 with respect to Chapter 4: Presentation of Data will help you.

Related Links:

- Class 11 Statistics for Economics Terms – Chapter 1: Introduction
- Class 11 Statistics for Economics Terms – Chapter 2: Collection of Data
- Class 11 Statistics for Economics Terms – Chapter 3: Organisation of Data
- Class 11 Statistics for Economics Terms – Chapter 5: Measures of Central Tendency
- Class 11 Statistics for Economics Terms – Chapter 7: Correlation
- Class 11 Statistics for Economics Terms – Chapter 8: Index Numbers
- Class 11 Statistics for Economics Terms – Chapter 9: Use of Statistical Tools