How to Choose a Data Visualization Method
Data visualization techniques are like spices in the kitchen: each chart or diagram helps highlight the features of a data set. Together with the head of the department Friflex design Svetlana Motorkina We figure out how to choose between line charts, bar charts, timelines, histograms and other visual communication methods.
What is data visualization
Data visualization is the translation of quantitative information (numbers, statistics, databases) into graphic information (graphs, charts, diagrams).
The purpose of visualization is to answer questions that a user might have. For example, graphs in fitness apps show how many steps and kilometers a user has walked, what their heart rate was, and how much time they spent.
Information visualization is used in a variety of industries, from scientific research to news and corporate reporting. Data can be presented in line charts, histograms, pie charts, or scatter plots.
Principles of visualization
Accuracy. Data must be accurate and complete. When a designer visualizes information, he or she must convey it without distortion. This way, the graph or chart will become a reliable source that the user will trust.
Benefit. Visualizations should help navigate the data with context. For example, a graph should have explanations: axis labels, notes, and titles. These help the user understand what the data is saying. Context helps interpret and make informed conclusions.
Scale. Visualization needs to be adapted to devices of different sizes. This way the reader will be able to read the data and see the details.
Types of visualization
Change graphs reflect data for a certain period.
They are used when you need to show trends or compare something across multiple categories. For example, to show price dynamics, health statistics for different periods, or to show a chronology.
Ratings, or ranking charts, are used to display the position of an element in an ordered list of graphs. For example, rankings are suitable when you want to show the difference between the results of candidates in elections.
Part-to-Whole Diagrams show how individual elements fit together to form the overall picture. For example, a budget structure diagram might look like a pie, with each slice representing a different type of income.
Correlation diagrams show relationships between variables. They are often used to show income or life expectancy.
Relationship diagrams convey how elements are related to each other or how they interact. Relationship diagrams are often used to analyze social networks. They can show who is at the center of the network, who is on the periphery, and what groups are forming.
Flow charts show how data moves through a system or program. These diagrams are often used to demonstrate how a neural network works. They clearly show how the AI receives information, processes it, and produces a result.
How to choose a visualization type
Set a goal. What do you want to convey to your audience? Show a trend over time, compare categories, analyze the structure of an object, or demonstrate correlations?
Determine the data typeThey can be numerical, categorical, geographic or other.
Study your audienceThe audience's level of knowledge, context, and other factors influence the choice of visualization method.
Select complexity and volumeSimple data looks good on histograms or line graphs, while complex data looks good on heat maps or bubble charts.
Don't forget about context and devicesThe smaller the screen size, the simpler the type of visualization should be.
Popular types of charts
Most often, designers use:
line graphs;
histograms;
area charts or area diagrams;
bar charts;
pie charts.
Line charts express minor differences in the data.
Histograms are suitable when it is necessary to show significant differences, comparisons and rankings of data.
Area diagrams summarize the relationships between sets of data. They show how individual points relate to the whole.
There are two types of area diagrams: area diagrams and overlapping area diagrams.
Area charts are best used to display multiple time series. A time series is a sequence of numbers that are arranged over time. It shows how a phenomenon or metric evolves. Area charts show how the data varies greatly.
In overlapping area charts, time series overlap each other. Avoid using more than two time series. They can obscure the data and make it difficult to read.
Bar and Pie Charts help compare parts with the whole.
Bar charts or histograms show quantity through the length of the bar and use a common baseline.
Pie charts express parts of a whole using arcs or angles within a circle.
Bar charts are better at showing changes over time than pie charts. It is easier for the user to compare or see differences across bars of different lengths.
For example, the bar chart clearly shows how sales figures differ between this quarter and last quarter for Alpha, Beta, Gamma, and Delta.
Instead of a conclusion, we will simply leave a template that helps you choose a way to visualize your data. Do not forget that you first need to clearly define your goal, the type, complexity and volume of data, the target audience and the devices they use.
In the next article we will discuss how you can style your charts.
Read our other design articles: how to manage user attention,
