In today’s world, the importance of data is at its peak. Data, if organized and put to use, can be more informative than a book or a podcast. From big multinational companies to simple human beings, the need for data is ever increasing. There are many ways to represent and interpret data, such as bar graphs, histograms, pie charts, etc.
Bar Graph vs Histogram
The main difference between a bar graph and a histogram is that a bar graph can be used to represent discrete data i.e. data of different entities and kinds. Histogram, on the other hand, is used to represent non-discrete data, which belongs to a similar category. The bar graph is just a categorical representation, whereas the histogram is a graphical distribution of scrutinized data, which can be used for calculations.
A bar graph is used to represent, associate, and compare different categories of data in a pictorial form. Each bar is of equal width and assumes a shape according to the data. It is just a diagrammatic record of data of different kinds, which need to be compared for a purpose.
A histogram represents numeric data of different frequencies, plotted on a graph. The data is grouped in continuous frequency distributions, and the bars are associated with these distributions and not entities. The bars may or may not be of equal width, as this is not made for pictographic representation but statistical numeric distribution.
Comparison Table Between Bar Graph and Histogram
| Parameters of Comparison | Bar Graph | Histogram |
| Gap Between Bars | Gaps are left between the bars in a bar graph for comparison. | No gaps are left between the bars in a histogram, as the data is continuous. |
| Width | The width of each bar in a bar graph needs to be the same. | The width of the bars in a histogram may or may not be the same, as it depends on the data. |
| Rearranging Property | The bars of a bar graph can be rearranged, as the each bar represents a different entity and they are not related. | The bars of a histogram cannot be rearranged, as each bar represents the frequency of a particular class, written in a particular order. |
| Uses | It is used to compare categorical data of similar or different entities, which may or may not be related to each other. | It is used to represent frequencies of continuous classes. |
| Examples | A bar graph can be used to show the sale of burgers of different companies in a particular region. | A histogram can be used to represent the consumption of internet among people of different age groups. For example, 10 to 20 years, 20 to 30 years, and so on. |
What is Bar Graph?
Bar Graph or Bar chart uses parallel rectangular blocks or bars to represent grouped data. The bar graph is said to have been designed by William Playfair. As mentioned before, it represents discrete data that may be different from each other but needs to be categorically compared with each other. The size of the bar depends on the value of each variable.
A bar graph can be drawn both vertically and horizontally. Hence, there is no strict division of the X and the Y axes. One axis represents the variables or entities of the chart, and the other axis shows the range of numerical values of those variables. Apart from pictorial representation, this graph has limited use, such as basic comparison and limited arithmetical calculations.
The bars of a bar graph never touch, and there is a gap between them. This explains how they are different, and apart from the basic interpretations, no relation can be established between those entities. There are certain advantages of the bar graph, such as it provides easy-to-understand diagrams of complex data as well as it summarising large tabulated data.
However, it is not always useful as it fails to mention the causes or give a definite pattern to the tabulated data.
What is Histogram?
Histogram can be defined as a graphical representation of continuous numerical data grouped in a frequency distribution. The term was introduced and coined by Karl Pearson. The data is continuous and is of the same entity. Hence, there are no gaps left between the bars. The distribution of frequency is of the total number of observations present within a particular class or bin. A histogram is plotted on a graph paper, or a digital interface, where the class intervals are marked on the X-axis and the frequency distribution is marked on the Y-axis. Adjacent rectangular blocks or bars are plotted according to the value of each class. There are 4 types of histograms,
- Uniform Histogram: Such a histogram is drawn when the classes are small, and their frequencies are similar to each other. It has a uniform shape.
- Bimodal Histogram: This histogram has two peaks, and it generally occurs when two sets of data are represented.
- Symmetric Histogram: This histogram is a bell-shaped representation. If a vertical line is drawn in the middle of the histogram, it would be divided into equal shapes.
- Probability Histogram: This histogram is a pictorial representation of discrete data. It begins by selecting the class, and the height of each bar represents the probability of each outcome.
There are some shortcomings of histograms as well. A histogram only works with continuous data. Moreover, it is difficult to compare two data sets in a histogram.
Main Differences Between Bar Graph and Histogram
- A bar graph is used to represent discrete data, i.e. of different kinds of entities. A histogram is used for representing non-discrete data, i.e. of a similar kind and of the same entity.
- A bar graph is just a pictorial representation of data that represents categorical data. A histogram is a graphical representation of frequencies of data, which is numerical and distributed in classes.
- A bar in a bar graph represents the value exhibited by an individual entity. A bar in a histogram represents values or frequencies of a particular class, having a certain range.
- The bars of a bar graph can be rearranged as per the user’s need, as they are just categorical and not related. The bars of a histogram cannot be rearranged and should be drawn according to the ascending or descending class intervals.
- The width of the bars in a bar graph should be equal as this is made for comparison. The width of the bars in a histogram may or may not be equal and depends on the size and frequencies of different class intervals.
Conclusion
In conclusion, we can say that both the bar graphs and histograms are very different from each other. Their somewhat identical origin and structures make them look similar. However, the above-mentioned differences set them apart. Both the bar graphs and histograms have their uses and advantages, and hence, they cannot be preferred over the other.
Both of them are important tools in the study of statistics, where they handle different sets of data in different ways and help in representing and interpreting tabulated data. Hence, they not only save time but also help the firms, companies, industries, policymakers, etc., to draw important conclusions and take informed decisions thereafter.
References
- https://eric.ed.gov/?id=EJ1035637
- https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002128&utm_source=web&utm_medium=pdf&utm_campaign=ppu15