Types of Graphs and Charts for Data Analytics: Ultimate Guide and Examples
Charts and graphs play an important role in data analytics by providing visual clarity and context to large datasets. They give a visual overview of data elements, allowing analysts to better analyze and explain findings. Whether examining sales trends, customer behavior, or operational performance, these visual aids assist in uncovering actionable insights that drive strategic choices.
Description
A bar chart is one of the most popular forms of data displays. It displays categorical data using rectangular bars, with the length or height of each bar corresponding to the value it represents. Bars can be plotted either vertically (column chart) or horizontally (bar chart). Each bar represents a category, allowing you to compare different categories at a glance.
Uses
- Comparing Different Categories
Bar charts are extremely useful for comparing different types of data. A bar chart, for example, can be used to compare sales numbers for different goods, city populations, or the performance of several departments within a firm.
- Showing Changes Over Time (Discrete Time Axis)
When the time axis is discrete, such as years, months, or quarters, bar charts can efficiently depict changes in time. For example, a bar chart may be used to show annual income over many years, with each bar representing sales for a single year.
Best Practices
- Use Consistent Colors for Bars
To minimize misunderstanding, use the same colors for bars representing the same category on many charts. This allows the viewer to rapidly identify and compare categories without being distracted by the different hues.
Start the Y-Axis at Zero
Starting the y-axis at zero is critical for appropriately representing the proportions of the bars. If the y-axis does not begin at zero, it may mislead the observer by magnifying the disparities between the bars. This method guarantees that the data’s visual representation appropriately reflects its numerical values.
Line Chart
Description
A line chart is a style of data visualization in which information is shown as a sequence of data points known as’markers’ linked by straight line segments. This sort of chart is good for displaying trends over time because it allows you to observe how values change at set intervals. Each point on the line represents a distinct data value at a given period, and the lines linking these points help to show the general trend.
Uses
- Visualizing Trends Over Time
Line charts are very useful for displaying patterns over time. They aid in detecting patterns such as upward or downward trends, cyclical patterns, and other variations. For example, a line chart may be used to represent a company’s stock values over multiple years, demonstrating how they have climbed or declined over time.
- Comparing Different Data Sets Over the Same Time Period
When comparing various data sets over the same time period, line charts are an excellent option. Plotting numerous lines on the same chart allows you to readily compare how various variables behave over time. For example, you may compare the monthly sales numbers of several goods within a firm to see which performs better or worse over the same time period.
Best Practices
- Use Different Line Styles or Colors for Multiple Data Sets
To differentiate between many data sets on the same chart, use distinct line types (solid, dashed, dotted) or colors for each one. This aids in differentiating between data sets and makes the chart easier to read and comprehend.
- Ensure the Time Intervals Are Consistent
Consistency in time intervals is critical to proper portrayal. Make sure the intervals on the x-axis (time axis) are appropriately spaced. Irregular time periods can confuse the observer and misrepresent trends. For example, if you’re charting monthly data, ensure sure the months are evenly spaced on the chart.
Pie Chart
Description
A pie chart is a circular statistical visual split into slices that depict numerical quantities. Each slice of the pie symbolizes one category’s contribution to the overall. Each slice’s size is proportionate to the category’s value, allowing you to easily compare different areas of the entire.
Uses
- Showing the Composition of a Whole
Pie charts are useful for showing how a whole is split into several portions. A pie chart, for example, can be used to display the market share of several firms within an industry, budget distribution, or population composition by demographic groups.
- Comparing Parts of a Whole at a Single Point in Time
Pie charts are handy for comparing multiple categories at the same moment in time. They give a picture of how several sections contribute to the overall, making it simple to determine which categories are the greatest or smallest.
Best Practices
- Limit the Number of Slices to Avoid Clutter
To preserve clarity, restrict the number of slices in a pie chart. Too many slices might make the chart difficult to read and comprehend. As a matter of thumb, aim to keep the number of slices under eight. If you have many categories, try combining smaller slices into a single “Other” category.
Use Contrasting Colors for Different Slices
Use contrasting colors to differentiate between the slices. This helps to identify each group and improves the chart’s visual appeal. Avoid choosing comparable shades of the same hue, since this might make it difficult to distinguish between the slices.
Histogram
Description
A histogram is a bar graphic that depicts the distribution of a data collection. Unlike a normal bar chart, which displays categorical data, a histogram divides numerical data into ranges (also known as bins). Each bar in a histogram indicates the frequency of data points within a given range, making it an effective tool for displaying the form and distribution of continuous data.
Uses
- Understanding the Distribution of a Data Set
Histograms are typically used to analyze the distribution of a data collection. They assist in visualizing how data points are distributed over different ranges and can indicate patterns such as normal distribution, uniform distribution, or skewed distribution.
Identifying the Central Tendency, Dispersion, and Skewness
Histograms can show the data’s central tendency (mean, median, mode), dispersion (range, variance, standard deviation), and skewness (asymmetry). A histogram with a single peak (unimodal) shows that the majority of data points are concentrated around a central value, whereas a histogram with many peaks (multimodal) indicates that there are multiple clusters of data points.
Best Practices
- Use Appropriate Bin Sizes to Accurately Reflect the Distribution
Choosing the appropriate bin size is critical for correctly representing the distribution of data. Bins that are too large can oversimplify the data and mask critical nuances, whereas bins that are too tiny can introduce noise and make it difficult to discover relevant patterns. Experiment with different bin sizes to see which one best captures the data.
Ensure There Are No Gaps Between the Bars
A histogram’s bars should be contiguous to one other with no gaps, indicating that the data is continuous. Gaps between bars may mislead readers into believing that the data is categorical rather than continuous.
Scatter Plot
Description
A scatter plot is a style of data visualization in which dots indicate values for two distinct numeric variables. Each dot’s position on the horizontal (x-axis) and vertical (y-axis) axes represents a value for a single data point. Scatter plots are very effective for visualizing the relationship between two variables and detecting patterns or trends.
Uses
- Identifying Correlations Between Variables
Scatter plots are useful for determining relationships between two variables. Plotting data points on a scatter plot allows you to visually analyze if the variables have a positive, negative, or no association. For example, a scatter plot may be used to investigate the link between advertising costs and sales income.
Detecting Outliers and Trends in Data Sets
Scatter plots assist in identifying outliers and patterns in data sets. Outliers are data points that differ considerably from the broader pattern and may suggest abnormalities or exceptional circumstances. Observing the general distribution of the data points allows you to identify trends such as linear or nonlinear correlations.
Best Practices
Label Axes Clearly to Represent the Variables
Label the x and y axes to indicate which variables are being plotted. This allows viewers to grasp what each axis represents and analyze the data correctly. For example, if you’re comparing age to income, call the x-axis “Age” and the y-axis “Income.”
Use Trend Lines to Highlight Relationships Between Variables
Adding trend lines to a scatter plot might assist to emphasize the link between the variables. Trend lines, such as linear regression lines, offer a visual representation of the data’s direction and intensity. They can help you identify the general trend and determine the association between factors.
Bubble Chart
Description
A bubble chart is a scatter plot with a third dimension expressed by the size of the markers (bubbles). Each bubble’s position on the horizontal (x-axis) and vertical (y-axis) axes represents the values of two numerical variables, while the size of the bubble represents the value of a third variable. This sort of chart is good for illustrating intricate connections between three variables.
Uses
- Comparing and Showing the Relationships Between Three Numerical Variables
Bubble charts are useful for examining and visualizing relationships between three numerical variables. They allow you to examine how two variables interact while concurrently accounting for the effect of a third variable. For example, a bubble chart can depict the link between sales, marketing spend, and market share, with the size of the bubble representing market share.
- Visualizing the Weight of Different Factors
Bubble charts allow to show the relative weight or relevance of various aspects. Changing the size of the bubbles allows you to easily determine whether data points have greater or lower values for the third variable. This is important in cases like risk assessment, when you need to compare the influence of several factors at the same time.
Best Practices
- Use Varying Bubble Sizes to Represent the Third Variable Clearly
Ensure that the bubble sizes appropriately represent the third variable’s values. To provide clarity and prevent confusion, use a uniform and proportionate scale for bubble sizes. It may be useful to include a legend explaining the bubble size scale.
- Avoid Overlapping Bubbles to Maintain Clarity
To ensure clarity, avoid overlapping bubbles if feasible. Overlapping bubbles can conceal critical information and make it difficult for users to differentiate between data points. Consider utilizing transparency or arranging the bubbles in a way that reduces overlap. Tools such as “jittering” can be used to slightly modify the location of overlapping bubbles, making them more identifiable.
Area Chart
Description
An area chart is similar to a line chart, except that the region below the line is filled in. This filler visually enhances the chart and is especially good for displaying cumulative totals over time. Area charts are frequently used to show the evolution of data over a continuous interval or time period, and they may assist grasp the amount of change over time.
Uses
- Displaying How a Quantity Changes Over Time
An area chart is similar to a line chart, except that the region below the line is filled in. This filler visually enhances the chart and is especially good for displaying cumulative totals over time. Area charts are frequently used to show the evolution of data over a continuous interval or time period, and they may assist grasp the amount of change over time.
- Showing Part-to-Whole Relationships
Area charts may also be used to represent part-to-whole connections. When numerous data sets are piled on top of one another, the chart may show how each one contributes to the total. This is important in situations when you need to compare the contributions of multiple categories over time, such as the market share of various items.
Best Practices
- Use Transparency to Distinguish Overlapping Areas
When working with various data sets in an area chart, it’s critical to employ transparency to separate overlapping sections. This keeps the chart from getting crowded and ensures that all data sets are viewable. Adjusting the transparency allows you to create a clear and layered visual impression.
- Ensure Clear Labeling of Different Data Sets
Clear labeling is essential in an area chart, particularly when numerous data sets are involved. To identify between data sets, use legends, labels, and distinct colors. This allows viewers to easily comprehend what each region represents and how it relates to the overall data.
Box Plot
Description
A box plot, also known as a whisker plot, is a standardized method for depicting the distribution of a data set using a five-number summary: minimum, first quartile (Q1), median (Q2), third quartile (Q3), and maximum. It gives a visual depiction of the data’s dispersion and skewness, emphasizing the central tendency, variability, and existence of anomalies.
Uses
- Comparing Distributions Between Several Groups
Boxplots are very useful for comparing distributions across many groups. Displaying numerous box plots side by side allows you to readily evaluate the central tendency, dispersion, and variability of different data sets. This makes box plots an excellent tool for comparing different categories, treatments, and diseases.
- Identifying Outliers and Variability Within Data Sets
Box plots aid in spotting outliers, which are data points that fall outside of the normal range. They also give a clear view of variability within data sets by displaying the range, interquartile range (IQR), and overall spread. This information is critical for determining the distribution and consistency of data.
Best Practices
Use for Small to Moderate-Sized Data Sets
Box plots are best suited for small to medium-sized data sets. For really big data sets, alternative representations, such as histograms or density maps, may be more suited. Ensure that the data set is not very sparse, as this might make the box plot less helpful.
Clearly Label the Quartiles and Outliers
Label each component of the box plot, including the quartiles, median, and outliers. This allows users to better grasp the distribution and identify relevant statistical metrics. If required, add a legend or comments to describe the various components of the box plot.
Heatmap
Description
A heatmap provides data in the form of a matrix, with colors representing values. It generates a visual summary of information, making it simple to identify patterns, correlations, and anomalies in massive data sets. Each column in the matrix represents a data point, and the color intensity indicates the value.
Uses
- Visualizing Data Density
Heatmaps are ideal for visualizing data density, helping to identify areas of high and low concentration within a data set. This makes them useful in fields such as geographical mapping, where you can visualize population density, and bioinformatics, where you can see the expression levels of genes.
Showing the Correlation Between Two Variables
Heatmaps are useful for displaying the association between two variables. By showing the data in a grid style, you can quickly see how changes in one variable influence the others. This is especially useful in correlation matrices, where each cell reflects the correlation coefficient of two variables.
Best Practices
Use a Color Gradient to Represent Data Values
Use a continuous color gradient to represent data values, making sure the transition between colors is seamless. This allows visitors to comprehend the range of numbers at a glance. Choose a color palette that is easy to understand and has a clear contrast across different value ranges. Common options include gradient scales from blue to red or green to red.
- Avoid Using Too Many Colors to Maintain Readability
Avoid adding too many colors, as this might make the heatmap difficult to see and understand. Stick to a restricted color palette and make sure the contrasts between hues are plainly discernible. Use perceptually uniform color scales, which means that equal steps in data are interpreted as equal steps in color.
Gantt Chart
Description
A Gantt chart is a bar chart that depicts a project timetable. It shows the start and end dates of the project’s major components. Tasks are represented by bars, the length of which indicates the task’s duration. Gantt charts are commonly used in project management to visually represent project timetables, measure progress, and manage task dependencies.
Uses
- Project Management
Gantt charts are crucial tools for project management. They give a visual chronology of project activities, assisting project managers and teams in planning, coordinating, and tracking work. Gantt charts improve resource allocation, scheduling, and deadline management by presenting job sequences and durations.
Tracking Project Timelines and Dependencies
Gantt charts are useful for tracking project deadlines and dependencies. They make it clear which activities must be finished before others can begin, as well as how modifications to one job affect the overall project timetable. This visibility helps in spotting possible bottlenecks and ensuring that the project stays on pace.
Best Practices
Use for Projects with Distinct Tasks and Timelines
Gantt charts are best suited for projects with separate tasks and timeframes. Break the project down into digestible tasks, each with a specific start and finish date. Ensure that the tasks are well-defined and that the timeframes are reasonable.
Clearly Mark Task Durations and Dependencies
Clearly note job durations and any relationships between them. Use arrows or lines to express dependencies, indicating which activities rely on the accomplishment of others. This aids comprehension of the project’s critical route and successful work sequence management.
Waterfall Chart
Description
A waterfall chart is a form of column chart that shows the cumulative effect of positive or negative numbers inserted successively. It depicts how an initial value is influenced by a sequence of intermediate positive or negative values, ending in a final value.
Uses
- Visualizing the Incremental Impact of a Series of Data Points
Waterfall charts are useful for illustrating the progressive impact of a succession of data items. They show viewers how each data point affects the total shift, whether positive or bad. This is especially valuable in financial analysis, where you can demonstrate how various factors contribute to changes in revenue or profit over time.
Showing How an Initial Value is Affected by Intermediate Values
Waterfall charts show the effects of a sequence of intermediate positive or negative values on a starting value. By breaking down the shift into discrete phases, the chart clarifies the components that influence the ultimate outcome. This makes it easy to discover patterns, abnormalities, or areas that need more examination.
Best Practices
Use for Data Sets with a Logical Order
Waterfall charts are best suited for data sets that follow a logical order or series of events. Ensure that the data points are presented in a sensible order to demonstrate the cumulative effect. This allows viewers to track the evolution from the original number to the ultimate conclusion.
- Clearly Label Each Step to Explain Changes
Label each step in the waterfall chart to describe the changes that occur at each level. Include annotations or tooltips to offer further context or information about each data point. This improves understanding and ensures that viewers perceive the chart correctly.
Treemap
Description
A treemap is a technique for visualizing hierarchical data that uses built rectangles. Each branch of the hierarchy is represented by a rectangle, which is further split into smaller rectangles that represent sub-branches. The size of each rectangle represents a specific statistic, such as the relative value or size of each category in the hierarchy.
Uses
- Displaying Hierarchical Data
Treemaps are useful for displaying hierarchical data structures, with each rectangle representing a distinct level in the hierarchy. This allows you to easily examine the link between the parent and child categories, as well as how they contribute to the overall structure.
Comparing the Proportions Between Different Categories
Treemaps are excellent for comparing proportions across different categories in a hierarchy. Each rectangle’s size directly represents the relative importance or size of each category, allowing readers to easily determine which are larger or more relevant.
Best Practices
Use Clear and Distinct Colors for Different Categories
Assign clear and distinct colors to different categories or levels of the treemap. This allows visitors to readily distinguish between categories and grasp the composition of the data at a glance. Consider utilizing a sensible color scheme to ensure that neighboring rectangles do not blur together.
Keep the Hierarchy Simple to Avoid Clutter
Maintain a clear hierarchy to reduce clutter and make the treemap easy to understand. Limit the amount of levels and categories presented, focusing on the most important parts of the data. This guarantees that the treemap is clean and useful without overloading users with too much material.
Violin Plot
Description
A violin plot is a style of visualization that combines elements of a box plot with a rotating kernel density plot on either side. Compared to typical box plots, it gives a more detailed portrayal of data distribution across many variables.
Uses
- Comparing the Distribution of Data Across Multiple Categories
Violin plots are useful for examining the distribution of data across categories or groupings. They display the shape, spread, and central tendency of the data within each category, allowing you to easily discover differences in distribution between groups.
Visualizing the Density and Distribution of Data
Violin charts are very good for showing data density and dispersion. The breadth of the plot at a particular point shows the density of data points at that value, and the height represents the frequency or proportion of data points.
Best Practices
Use for Medium to Large Data Sets
Violin plots are best suited for medium to large data sets in which you wish to understand data distribution across multiple groups or factors. They give more comprehensive information about the shape of the distribution than typical box plots.
- Combine with Box Plots to Provide More Detailed Insights
Combining violin plots with typical box plots can improve visualization and analysis. This combination displays both summary data (such as quartiles and outliers) from box plots and the entire distribution from violin plots. This holistic picture aids in comprehending both the core trend and variability of the data.
Funnel Chart
Description
A funnel chart is a sort of chart that portrays phases in a process and displays the amount or quantity of data at each step. It usually begins with a large top and narrows down progressively to the bottom, symbolizing the diminishing amount or size as the process moves through each stage.
Uses
Visualizing Stages in a Process
Funnel charts are useful for illustrating phases in a process, such as a sales funnel or a customer journey. Each stage is represented by a funnel segment, the breadth of which is proportional to the amount of data at that level. This aids in understanding how data or humans progress through various phases of a process.
Identifying Bottlenecks in a Process
Funnel charts can help identify bottlenecks or areas for improvement in a process. Visually comparing the breadth of each segment allows you to identify stages with a considerable drop-off or where the process may be less efficient. This knowledge enables focused efforts to enhance processes and increase overall performance.
Best Practices
Clearly Label Each Stage
Make sure each stage of the funnel chart is properly labeled to reflect the relevant phase or step in the process. Labels should be descriptive and put next to or within each segment of the funnel. This allows viewers to grasp the flow and advancement of data across the phases.
Use for Processes with a Clear Flow
Funnel charts are best suited for processes with a clear and sequential flow, in which data or personnel go through discrete phases in a predetermined order. Avoid using funnel charts for processes with complicated or non-linear flows, as they can cause confusion and misinterpretation.
Bullet Chart
Description
A bullet chart is a sort of bar chart that compares a single metric to a goal value and preset ranges of performance. It gives a clear visual picture of how well a specific metric or performance measure meets its aim and where it stands within the stated ranges.
Uses
Displaying Performance Data
Bullet charts are frequently used to illustrate and compare performance data from several categories, such as sales numbers, KPIs (Key Performance Indicators), and operational measures. They enable stakeholders to swiftly analyze performance levels and highlight areas requiring attention or improvement.
Showing Progress Towards Goals
Bullet charts are useful for visually representing progress toward goals or targets. They give a full perspective of performance status at a glance by displaying the actual performance measure in relation to a goal value and predetermined ranges (such as bad, sufficient, and good).
Best Practices
Use Distinct Colors for Target, Actual Value, and Ranges
Use various colors to distinguish between the goal value, actual performance measure, and predetermined ranges in the bullet chart. This color coding improves clarity and allows viewers to comprehend the graphic more quickly.
Keep the Design Simple to Emphasize Key Metrics
Maintain a minimal, uncomplicated style to highlight the main data offered in the bullet chart. Avoid unimportant embellishments or items that might detract from the chart’s essential message of comparing performance to objectives and ranges.