"After transforming table values into data points and plotting them all on the plane, we’ll get a cloud of data points where we get an accurate representation of their relative distances. This is the stepping stone for everything we’ll do afterwards, because a lot of things start to happen when we see and compare distances between data points or between each of them and the axes. What will we do with this cloud? Essentially, we’ll make it visible by, for example, using lines to connect data points and creating a line chart. These complementary primitives play a key role in the way we’ll read the chart and how effective it will become." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Because we should, whenever possible, try to understand relationships between variables and not only describe each one of them in isolation, scatter plots are the most powerful charts available to us. The connected scatter plot is not easy to read at first, but I strongly encourage you to become familiar with it - at least during the exploratory stage - to check for relevant shapes in the relationships. Whenever you feel the need to use a dual-axis chart with two independent variables, you should try the connected scatter plot first." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Being aware of the limits of our perception helps us not only to choose a display that respects these limits, but also to find devices that minimize them." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"But here’s the contradictory thing about pie charts. A common argument in favor of pie charts is that reading the labels compensates for what really are our difficulties in reading them accurately. […] this is not an argument in favor of pie charts; rather, it’s an argument to the detriment of visualization. Shouldn’t we be able to read the chart without deciphering all the labels? If we have to read both the labels and the chart, the chart becomes pointless, as labels should complement rather than entirely support it." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Chart selection ultimately boils down to two things: what the task is really about, and the trade-offs you’re willing to accept." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Charts are always an interpretation of data, in the same way that a photo is an interpretation of reality, no matter how objective it may seem. This should be not only recognized but encouraged within an ethical framework that seeks to identify its own subjectivity and minimize its influence on choices. There can be no contradiction between 'what I want to say' and 'what the data say'. This difference is often difficult to detect, especially when the subject’s message is fully determined by his beliefs, ideological position, and activism." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Color is just a complicated physiological phenomenon associated with symbolic, aesthetic, and emotional qualities. Each of these qualities is enough by itself to wreak havoc in data visualizations if not treated with care. Together, they make disaster almost inevitable […]" (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Complementary colors send a message of opposition but also of balance. A chart with saturated complementary colors is an aggressively colored chart in which the colors fight (equally) for their share of attention. Apply this rule when you intend to represent very distinct variables or those that for some reason you want to show as contrasting each other. Do not use complementary colors when variables have some form of continuity or order." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Data stories are a subset of the much broader concept (or buzzword) of storytelling. […] Stories, or narratives, are useful in data visualization because they force us to recognize the limited value of a single chart in a complex environment. Stories also force us to recognize the need for a better integration of our displays, as we move away from strings of siloed charts." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"[...] data visualization [is] a tool that, by applying perceptual mechanisms to the visual representation of abstract quantitative data, facilitates the search for relevant shapes, order, or exceptions. [...] We must think of data visualization as a generic field where several (combinations of) perspectives, processes, technologies, and objectives (not forgetting the subjective component of personal style) can coexist. In this sense, data art, infographics, and business visualization are branches of data visualization." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Data visualization is marketed today as the miracle cure that will open the doors to success, whatever its shape. We have enough experience to realize that in reality it’s not always easy to distinguish between real usefulness and zealous marketing. After the initial excitement over the prospects of data visualization comes disillusionment, and after that the possibility of a balanced assessment. The key is to get to this point quickly, without disappointments and at a lower cost." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Data visualization is not a science; it is a crossroads at which certain scientific knowledge is used to justify and frame subjective choices. This doesn’t mean that rules don’t count. Rules exist and are effective when applied within the context for which they were designed." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"'Distribution' refers to how the vof a variable are placed along an axis, keeping the proportional distances taken from the values in the table. In descriptive statistics, there are two complementary ways to study a distribution: searching for what is common (the measures of central tendency) and searching for what is different along with how much different it is (measures of dispersion)." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Donuts appear to have the advantage over pie charts of allowing for the comparison of multiple series, one in each ring, which makes them the circular version of stacked bar charts. In fact, though, there is little value in this, for it only helps to compare the first and last values of each series, just like the stacked bar chart." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Even a small table can answer many questions, and there are a variety of chart types we can choose from to answer these questions." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"For every rule in data visualization, there is a scenario where that rule should be broken. This means that choosing the best chart or the best design is always a trade-off between several conflicting goals. Our imperfect perception means that data visualization has a larger subjective dimension than a data table. Sometimes we only need this subjective, impressionist dimension and other times we need to translate it into hard figures. Striving for accuracy is important, but it’s more important to provide those insights that only a visual display can reveal." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Form simplification means simplifying relationships among the components of the whole, emphasizing the whole and reducing the relevance of individual components by standardizing and generalizing relationships. This results in an increased weight of useful information (signal) against useless information (noise)." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"From a functional point of view, colors per se don’t really matter, and if you can avoid strong symbolic meanings, it doesn’t matter if you pick them randomly. Data visualization deals with discriminating among visual stimuli, defining their relationships, and establishing the intensity of these stimuli. The colors you pick just need to meet these requirements. Realizing this helps us overcome our fears of aesthetic catastrophe." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Graphical literacy, or graphicacy, is the ability to read and understand a document where the message is expressed visually, such as with charts, maps, or network diagrams." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Grouping charts according to a theme and in sequence with the message and putting them all on the same sheet or slide helps you find the thread of the message (even if the charts are separated again later)." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"It’s imperative that you find an alternative visualization model. One that makes you feel comfortable and through which you’re able to analyze the data and communicate your findings effectively. This is something you have to do by yourself, depending on your tasks, your skills, your organization’s requirements, and the tools that it allows you to use." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"It’s important to note that parsimony and simplicity are not absolute principles. We should not take them to the extreme and risk losing useful elements for understanding." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Like a pie chart, a treemap is used for a part-of-a-whole analysis, but because you have better control over the rectangle sizes than over slices, you can have many more data points. Unlike with traditional pie charts, you can arrange the data hierarchically. You can compare a rectangle to all data points or to its own branch." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Making multiple individual charts is like jotting down unstructured thoughts on pieces of paper. At some point, you will start to repeat some thoughts and forget others. Joining these charts in sequence and trying to form a coherent sentence from their titles will help you focus on your priorities. Resist the temptation to make charts that try to respond to too many questions. Be aware also that, by making something interesting, you’re not actually hiding or demoting what is relevant." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Optical illusions show how the context and the interaction of objects lead us to a wrong assessment of their properties." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Tailoring the message to the audience should not be synonymous with accepting its prejudices, routines, and the usual ways of doing things. Many of what we believe to be good data visualization principles are opposite to what is practiced within organizations. When presenting a chart type the audience is unfamiliar with, or when breaking a rule, the author must argue for its advantages. Annotating the chart, showing how to read it, drawing aention to key points, and making direct comparisons with alternative representations will help the audience feel safer in their reading and possible adoption of the new chart." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The ability to manipulate geometric primitives and the retinal variables […] is not enough to guarantee a 'tasty' visual representation." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The ability to see meaningful shapes in the data represents the highest level of data visualization, because it represents the highest level of data integration and a richer graphical landscape. Line charts and scatter plots are frequently used for this shape visualization." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The first and most important functional quality of color is its suitability to the task. For example, color selection differs depending on whether you want to encode either a categorical variable or a variable with a continuous range of values. The second functional quality of color is stimuli intensity. Pure primary colors and pastel colors have different intensity levels, which allow us to establish various levels of chart reading and evaluate the stimulus intensity of each object on the chart. The final functional quality of color is, in a broad sense, its symbolism." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The first requirement for a chart not to lie is, naturally, that the data don’t lie either. […] One of the most transverse and insidious forms of a lie is the conflict between the perceptual and cognitive dimensions of a chart. As we know, what we see in the chart can’t be corrected by the legend or other objects." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The law of connectivity tells us that objects connected to other objects tend to be seen as a group. […] The law of common fate tells us that objects moving in the same direction are seen as a group." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The law of continuity states that we interpret images so as not to generate abrupt transitions or otherwise create images that are more complex. […] we can arbitrarily fill in the missing elements to complete a pattern. It’s also the case of time series, in which we assume that data points in the future will be a smooth continuation of the past. […] In a line chart, those series with a similar slope (that is, they appear to follow the same direction) are understood as belonging to the same group." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The law of segregation tells us that objects within a closed shape are seen as a group. A frame around objects (charts or legends, for example) has this function, but it’s also useful for adding visual annotations." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The most pragmatic way of beginning the data visualization process is with a question, and then making a chart that answers that question. […] Certain charts are better suited to answer certain questions than others, but you should take this relationship as a broad principle. Subtle changes in the question and in the chart design can impact the results. Having a clear goal in mind and knowing what type of visualization could be more effective can help us reduce the range of options of chart types and design choices." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The use of dual-axis charts is a subtle form of graphical lie through which [...] a spurious relationship is established between variables. Considering that the author of a dual-axis chart tries to harmonize the representation, it’s natural to break some rules: The vertical scale is one of the first victims." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"The 'whole', expressed in absolute or relative terms, is central to any composition chart. No matter what, the whole must be displayed in each and every composition chart." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"There can be several reasons why someone breaks the rules, whether from ignorance, malice, or the sincere desire to find a more effective way to explore the data or communicate the results. Whatever the reason, breaking the rules frustrates the audience’s expectations and will incur a cost. Sometimes you might consider this an investment, while often it is nothing more than waste." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Unfortunately, setting the scale at zero is the best recipe for creating dull charts, in both senses of the word: boring and with little variation. The solution is not to break the scale, but rather to find a similar message that can be communicated using alternative metrics." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Using sparklines is not as simple as it might seem. You must ensure that variation is as clear as possible. […] Sparklines are an interesting concept, but there are a few issues associated with their extreme miniaturization, among which is the removal of the vertical axes and the consequent absence of quantitative references." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Visual clutter is one of the most serious issues with bar charts. Using a bar to represent a simple data point is clearly overkill that results in no room for more data. At times, this may make us overlook less obvious things. The population pyramids offer a glaring example of this. But dot plots are not only about reducing clutter and avoiding overstimulation. Because we don’t compare heights, dot plots actually allow us to break the scale to improve resolution, and that’s a big plus over bar charts." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"We can use visualization to support the validation and assessment of data quality because the genesis of an outlier may be in the data collection stage or from incorrect data entry. In most cases, however, the outlier is a legitimate value that appears again in other variables. Whatever the case, an outlier should always be examined and explained." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"We must not rush to conclude that we should always select the encoding that ensures a maximum degree of precision, which in practice would result in the exclusive use of dot charts, since those represent the example of 'position in a common scale'." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"We tend to see closed objects, objects seen as a unit, or objects that look smaller as the object that stands out from the amorphous background." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"When we use the number of dimensions as the classification criterion of visual displays, we get four distinct groups: charts, networks, and maps, along with figurative visualizations as a special group." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)
"Your goal when designing a scattr plot is to make the relationship between two variables as clear as possible, including the overall level of association but also revealing clusters and outliers. This is easier said than done. The data and a few bad design choices can make reading a scaer plot too complex or misleading." (Jorge Camões, "Data at Work: Best practices for creating effective charts and information graphics in Microsoft Excel", 2016)