Data Interpretation Syllabus and Study Material
Data Interpretation bears the closest resemblance to the kind of problems that you as a manager would be tackling in your professional career. Data Interpretation has no particular syllabus. In Data Interpretation tests the questions will test your speed, decision making capability and analysing data. The questions consists of a graphs, charts and tables from which you will have to analyse data. Quickly identify the key pieces of data that you will require to work on the questions asked is the key to crack the problem.
Data represented in the form of a table is quite time consuming to analyses such as trends, problem areas, percentage distribution. Graphs on the other hand represent the same data visually and we can easily see the trends and distribution. Even problem areas are easy to identify by looking at the deviation from the trends. Representing data in the form of caselets is quite uncommon, however, it is very popular with car examiners. In this case, date is hidden between paragraphs and you have to unearth the data as you go on reading the paragraph. This is probably the worst case of data representation when it comes to analyzing and drawing conclusions out of it.
Data Sufficiency problems usually take the form of a logical puzzle, and are in the form of a question followed by two statements. The key to answering such problems is to pretend like one statement does not exist, try solving the problem, and then pretend like the other statement does not exist and try solving the problem again. These problems are generally tricky, and I would recommend lots of practice and perhaps solving them near the end of your section, after you have solved the other problems.
Some tips to score better in the Data Interpretation section:
1. Read the Question in parts: Most Data Interpretation questions will consist of a bunch of statistics, numbers & diagrams that might look scary, but are actually not at all difficult to solve. In fact the trend has been: the scarier a DI set/caselet looks, the easier it is to solve.
2. Improve your Calculation Skills/Speed: The Date Interpretation section is calculation-intensive. Such calculations can eat up your time. Learn shortcuts that will help you calculate fast.
3. Get familiar with all types of Data Interpretation questions: There will be bar charts, tables, pie charts etc. There will also be questions where a lot of text/information will be provided in 1 long paragraph.
4. Practice, practice, practice: With a very good amount of practice your speed and confidence will increase considerably.
Tabular method is the most fundamental way of representing data. In fact, most of the different kinds of data presentation formats like the bar charts, line charts etc. originate from the table. In other words, presenting the data in a tabular format is the first step in forming other types of data presentation formats.
While tables express actual numbers, graphs are a diagrammatic representation of data. They bring out the relationship between data more clearly than numbers in a table. Graphs are far better to understand changes in variables - whether a particular value has risen or fallen over the past few years and hence analyze the trends.
They always represent data in the form of a percentage of the total, with the total percentage being 100. In such a chart, the length of the arc (and therefore the angle each sector subtends at the centre) is proportional to the quantity it represents. Such charts are often used in the corporate world and in newspapers. Since a circle comprises 360 degrees, each percent of a pie-chart is equal to 360 divided by 100, or 3.6 degrees. This fact will be important for the calculations you are expected to perform.
Bar graphs represent data in the form of columns or bars. Bar graphs can be horizontal or vertical. The length of the bar is proportional to the data value represented by it.
Line graph represents data in the form of straight lines that connect various data values. Both line graphs and bar graphs are used to convey same things and hence can be used inter-changeably. For example, a line graph can be generated by joining the tip of the bar graph.
In caselets, the mathematical data is represented in the form of a paragraph. Hence extracting data and establishing relationships between different data values becomes difficult. However caselets are very popular with the CAT examiners.
Combined Data Sets
Data is represented in two or more different types of data sets. It could be combination of a table and a graph or two or more graphs. You may have to correlate the data in different data sets to solve these questions.
Data Interpretation questions typically have large amounts of data given in the form of tables, pie-charts, line graphs or some non-conventional data representation format. The questions are calculation heavy and typically test your approximation abilities. A very large number of these questions check your ability to compare or calculate fractions and percentages. If you sit down to actually calculate the answer, you would end up spending more time than required. Here are few ideas that you can use for approximation.
A Summary of Strategies for Charts, Tables, and Graphs
- Examine the entire graph, noticing labels and headings.
- Focus on the information given.
- Look for major changes—high points, low points, and trends.
- Don’t memorize the chart, table, or graph; refer to it.
- Skimming questions can be helpful.
- Circle or underline important words in the question.
- Pay special attention to which part of the chart, table, or graph the question is referring to.
- If you don’t understand the graph, reread the labels and headings.
Don’t get stuck on any one question!