What Is A Graph?
Graphs and charts are visual representations of data in the form of points, lines, bars, and pie charts. They are convenient ways of displaying large quantities of information in the form that is quick and simple to understand. Using graphs or charts, you can display values you measure in an experiment, sales data, or how your electrical use changes over time.
Types of graphs and charts include diagrams, tables, maps, line graphs, bar graphs, and circle/pie charts. Different types of graphs and charts display data in different ways, and some are better suited than others for different uses. To interpret a graph or chart, read the title, look at the key, read the labels. Then study the graph to understand what it shows.
Importance of Graphs to have a Clear Idea:
Graphs are undoubtedly a handy way to depict your data in an apparent manner. You just need to make sure the way to display your results with correct graph form. The x and y axes on bar and line graphs ought to be correctly labeled with appropriate units of measure. You can use metric units to label these axes. The line, bar, and circle graph depicts different types of data and below mentioned is a general description of these graphs:
Bar Graph:
You can use bar graphs to display the relationship among groups. Any two items that you will be comparing need not necessarily influence each other in any way. It is also a quickest way to display huge difference.
Line Graph:
You can use line graphs to depict continuing data, for how one thing is influenced by the other. You can clearly see how things are progressing by the fluctuations shown in line graph. Such types of graphs are necessary to display the consequence of independent variables on dependent variables. For example, pulse rate of a person is clearly viewable in a line graph. Since, the time continues and the pulse rate keeps on changing.
Circle or (Pie) Graph:
A pie graph or circle graph will help you to display a part of something that relates to the whole. Usually, circle graphs are a key way to show percentages efficiently.
Area Graph:
You can use area graphs to display things, which change over time. These graphs have an x-axis (horizontal) and a y-axis (vertical). Generally, the x-axis denotes the time scale, whereas the y-axis denotes what you are measuring.
You can use area graphs specifically, when you think to plot data that has ups (peaks) and downs (valleys) or for data collected over a short period.
One real example of area graph would be the graph required to show percentage of high school graduates, who have completed advanced English courses over a period.
Some graphs are easy to understand, while some are a bit complicated. You have to be a bit careful while you work on graphs, as there are several types of graphs with each one having moderate and definite use.
A good graph
accurately shows the facts
grabs the reader's attention
complements or demonstrates arguments presented in the text
has a title and labels
is simple and uncluttered
shows data without altering the message of the data
clearly shows any trends or differences in the data
is visually accurate (i.e., if one chart value is 15 and another 30, then 30 should appear to be twice the size of 15).
Why use graphs when presenting data?
Diagrams...
are quick and direct
highlight the most important facts
facilitate understanding of the data
can convince readers
can be easily remembered
Is it always appropriate to use a graph?
You might want to reconsider the use of a graph when
the data are very dispersed
there are too few data (one, two or three data points)
the data are very numerous
the data show little or no variations
Consider the following instructions and their appropriate terms when labelling the graph or describing features of it in an accompanying text:
| Determine the nature of the message | ||
| If your graph will... | Use the following terms... | |
| describe components | share of, percent of the, smallest, the majority of | |
| compare items | ranking, larger than, smaller than, equal to | |
| establish a time series | change, rise, growth, increase, decrease, decline, fluctuation | |
| determine a frequency | range, concentration, most of, distribution of x and y by age | |
| analyse relationships in data | increase with, decrease with, vary with, despite, correspond to, relate to | |
| do any combination of the above actions | e.g., 'percentage of dropouts among the 15 to 24 age group has increased because of....' | |
Experiment with different types of graphs and select the most appropriate.
1. pie chart (description of components)
2. horizontal bar graph (comparison of items and relationships, time series)
3. vertical bar graph (comparison of items and relationships, time series, frequency distribution)
4. line graph (time series and frequency distribution)
5. scatterplot (analysis of relationships)
Useful Expressions for Describing Graphs
1. Going up
· A little
| nouns | verbs |
| An increase увеличение A rise подъем A growth рост An improvement улучшение An upturn An upward trend тенденция к повышению | To increase To rise To grow To improve To go up |
· A lot
| A surge подъем, рост, волна An upsurge A jump A leap скачок | To surge To jump To leap To take off взлетать To shoot up To soar воспарить To rocket взлетать |
Going down
· A little
| A decrease A fall A drop A decline A downturn спад A downward trend тенденция к понижению | To decrease To fall (off) To drop To decline To go down To slip соскальзывать |
· A lot
| A plunge крутой спуск, погружение A slump резкое и внезапное падение A crash обвал A tumble падение | To plummet быстро и отвесно падать To plunge To slump To crash To tumble To sink тонуть |
2. Changes
| No change | Peaks | Low points |
| To remain stable To level off выравниваться To stay at the same level To remain constant To stagnate застаиваться To stabilize | To peak To reach a peak To top out достигать высшего уровня, высшей точки | To reach a low point To bottom out достичь нижнего предела перед фазой оживления To recover возвращать(ся) исходное положение To rebound скачок вверх; быстрое повышение, восстановление To revive восстанавливаться |
The degree of change
| adjectives | adverbs |
| A dramatic внезапный и существенный rise or fall - Considerable значительно - Sharp резко - Significant значительный - Substantial существенный - Moderate умеренный - Slight легкий | To rise or fall dramatically - considerably - sharply - significantly - substantially - moderately - slightly |
The speed of change
| adjectives | adverbs |
| An abrupt крутой, внезапный rise or fall A sudden - rapid быстрый - quick - steady устойчивый - gradual постепенный - slow медленный | To rise or fall abruptly - suddenly - rapidly - quickly - steadily - gradually - slowly |
Prepositions
To rise\fall from …to…
To increase\fall by 100%\50% на
A decrease of 15 % на