Question 1

Answer the following questions for this graphic Relationship between ages and psychosocial maturity

  1. Identify the visual cues, coordinate system, and scale(s)
    Visual cue: bar chart with different colors for ‘Menarche’ and ‘Phychosocial maturation’.
    Coordinate system: Cartesian x-y coordinates, with the x-axis being time and y-axis being age of menarche and phychosocial maturation.
    Scale: scale of time is in 4 categories, being ‘20000 years ago’, ‘2000 years ago’, ‘200 years ago’ and ‘Present’. The scale of Age is in numerics, on the plot it ranges from 0 to 20.

  2. How many variables are depicted in the graph? Explicitly link each variable to a visual cue that you listed above.
    There are three variables in the graph: Time, Age and Event (Menarche vs Phychosocial maturation). Time is the x-axis, Age is the y-axis while menarche vs Phychosocial maturation is depicted by the different colors of the bars.

  3. Critique this data graphic using the taxonomy described in the lecture.
    This data graphic overall does a good job telling the story of how, for human societies, menarche and psychological maturation have been happening around similar age since 20000 years ago, but coming into present time, the ages for phychosocial maturation and menarche have been diverging, with phychosocial maturation happening at a significantly older age than menarche. The x-axis groups Time into 4 categories and clearly shows how menarche/phychosocial maturation age evolved over time. The y-axis has Age displayed in nominal numbers. Menarche/phychosocial maturation age ranges then appear as bars on the graph, in different colors, with bars for different time connected by a straight line of the corresponding color. One critique would be it is a bit unclear whether the point where the line goes out indicates the group mean.

Question 2

Answer the following questions for this graphic World’s top 10 best selling cigarette brands 2004-2007

  1. Identify the visual cues, coordinate system, and scale(s)
    Visual cues: This chart is a horizontal bar chart, with sales of 10 cigarette brands displayed as bars in different colors. In addition, this chart includes a chart title that clearly tells the audience what this chart is about and also a x-axis label that denotes the unit of accounting for the sales.
    Coordinate system: Cartesian x-y coordinates, with x-axis being sales in billions and y-axis being the different cigarette brands.
    Scale: X-axis uses a numeric scale, with values ranging from 0 to 500 billion dollars. Y-axis uses a categorical scale, with each category being a different cigarette brands.

  2. How many variables are depicted in the graph? Explicitly link each variable to a visual cue that you listed above. Two variables are depicted in the graph, cigarette brands and sales in billions. Sales in billions is displayed on the x-axis, and cigarette brands are displayed on the y-axis.

  3. Critique this data graphic using the taxonomy described in the lecture.
    This data graphic uses a horizontal bar chart to display the sales of world’s top 10 best-selling cigarette brands, with chart topic clearly represented in the chart title, and the unit of sales denoted in the x-axis label. The author did not include a y-axis label, and that is because the names of different cigarette brands are already included on the y-axis, and therefore a y-axis label is redundant. The author also used different colors to plot the bars, making the graph easier to read.

Question 3

Find two data graphics published in a newspaper on on the internet in the last two years.

  1. Identify a graphical display that you find compelling. What aspects of the display work well, and how do these relate to the principles that we have just gone over in lecture. Include a screenshot of the display along with your solution (Hint:use the following in a code chunk: knitr::include_graphics(“your_graphic”).

The following chart shows the global temperature change since 1880, compared to NASA’s 1951-1980 baseline. Since the data visualization module is interactive, the screenshot is taken when 2021 is selected. So the screenshot actually shows the temperature change from NASA’s 1951-1980 baseline to 2021. This chart uses a geographic coordinate, with areas of the world having different temperature difference assigned to different color hues. And color hue is then explained at the bottom on a numerical scale. This graphical display is compelling because by using the color scale, it clearly shows that the areas that have the largest temperature change are areas surrounding the North Pole, and the change is positive (displayed in bright red). Therefore it visually tells the story of global warming in the 21st century.

knitr::include_graphics("graph1.png")

  1. Identify a graphical display that you find less compelling. What aspects of the display don’t work well? Are there ways that the display might be improved? Include a screenshot of the display along with your solution (Hint:use the following in a code chunk: knitr::include_graphics(“your_graphic”).

According to the internet, the following graph shows some measure of voting among men and women in India from 1967 to 2019 But without this explanation, there is actually no way of telling which country this chart is about. The chart is also missing the y-axis label, without which we have no clear idea what is the measure used for voting. The chart does have a legend explaining the two series, Men Voters and Women Voters, but combined with the backgraound color used, it is a very poor choice of color scheme as the colors are too similar that it is hard to read.

knitr::include_graphics("graph2.png")

Question 4

Briefly (one paragraph) critique the designer’s choices. Would you have made different choices? Why or why not? Note: Link contains a collection of many data graphics, and I don’t expect (or want) you to write a full report on each individual graphic. But each collection shares some common stylistic elements. You should comment on a few things that you notice about the design of the collection.

What is a Data Scientist

Answer:
I liked how the designer chose to use the same color palette for this collection of charts, as it looks more uniform and is easier to read and understand. I also appreciate how the designer wrote chart titles in similar styles, incomplete sentences, that guide the readers to find the answers themselves in the charts. The designer also made smart choices in terms of color and font, with the most important part of each graph depicted in darkest color (or color of highest saturation) and biggest font, so that it’s easier to grab audence’s attention. There is one thing I would change for the first chart: the explanation is misleading since it says “over 2/3 believe demand for talent will outpace the supply of data scientists”. This statement seems to be false since below the numbers shows 63%, which is less than 2/3, of the people surveyed believe demand will outpace supply of talent.

Question 5

Briefly (one paragraph) critique the designer’s choices. Would you have made different choices? Why or why not? Note: Link contains a collection of many data graphics, and I don’t expect (or want) you to write a full report on each individual graphic. But each collection shares some common stylistic elements. You should comment on a few things that you notice about the design of the collection.

Charts that explain food in America

Answer:
Compared to the collection in Question 4, these charts are definitely harder to understand. They all lack chart titles that explains what the chart is about, so that the only way to read them is to read the text next to them. This make them less compelling since a good chart will save readers time by conveying text in a visual format. These charts also have different color hues and fonts, and that makes them look chaotic and requires more attention for readers to dive in and figure out what the chart is trying to say.