Assignment 1: Visualization Design

In this assignment, you will design a visualization for a small data set and provide a rigorous rationale for your design choices. You should in theory be ready to explain the contribution of every pixel in the display. You are free to use any graphics or charting tool you please – including drafting it by hand. However, you may find it most instructive to create the chart from scratch using a graphics API of your choice.

(See Resources for a list of visualization tools.)

Data Set: U.S. Population, 1900 vs. 2000

Every 10 years, the census bureau documents the demographic make-up of the United States, influencing everything from congressional districting to social services. This dataset contains a high-level summary of census data for two years a century apart: 1900 and 2000. The data is a CSV (comma-separated values) file that describes the U.S. population in terms of year, reported sex (1: male, 2: female), age group (binned into 5 year segments from 0-4 years old up to 90+ years old), and the total count of people per group. There are 38 data points per year, for a total of 76 data points.

Dataset: CSV
Source: U.S. Census Bureau via IPUMS

Your Tasks

  1. Start by choosing a question you'd like a visualization to answer.
  2. Design a static visualization (i.e., a single image) that you believe effectively answers that question, and use the question as the title of your graphic.
  3. Provide a short write-up (no more than 4 paragraphs) describing your design.

While you must use the data set given, you are free to transform the data as you see fit. Such transforms may include (but are not limited to) log transformation, computing percentages or averages, grouping elements into new categories, or removing unnecessary variables or records. You are also free to incorporate external data as you see fit. Your chart image should be interpretable without recourse to your short write-up. Do not forget to include title, axis labels or legends as needed!

As different visualizations can emphasize different aspects of a data set, you should document what aspects of the data you are attempting to most effectively communicate. In short, what story are you trying to tell? Just as important, also note which aspects of the data might be obscured or down-played due to your visualization design.

In your write-up, you should provide a rigorous rationale for your design decisions. Document the visual encodings you used and why they are appropriate for the data and your specific question. These decisions include the choice of visualization type, size, color, scale, and other visual elements, as well as the use of sorting or other data transformations. How do these decisions facilitate effective communication?


The assignment score is out of a maximum of 10 points. Historically, the median score on this assignment has been 8.5. We will determine scores by judging both the soundness of your design and the quality of the write-up. We will also look for consideration of audience, message and intended task.

We will use the following rubric to grade your assignment. Note, rubric cells may not map exactly to specific point scores.

Component Excellent Satisfactory Poor
Data Question An interesting question (i.e., one without an immediately obvious answer) is posed. The visualization provides a clear answer. A reasonable question is posed, but it is unclear whether the visualization provides an answer to it. Missing or unclear question posed of the data.
Mark, Encoding, and Data Transforms All design choices are effective. The visualization can be read and understood effortlessly. Design choices are largely effective, but minor errors hinder comprehension. Ineffective mark, encoding, or data transformation choices are distracting or potentially misleading.
Titles & Labels Titles and labels helpfully describe and contextualize the visualization. Most necessary titles and labels are present, but they could provide more context. Many titles or labels are missing, or do not provide human-understandable information.
Design Rationale Well crafted write-up provides reasoned justification for all design choices. Most design decisions are described, but rationale could be explained at a greater level of detail. Missing or incomplete. Several design choices are left unexplained.
Creativity & Originality You exceeded the parameters of the assignment, with original insights or a particularly engaging design. You met all the parameters of the assignment. You met most of the parameters of the assignment.

Submission Details

This is an individual assignment. You may not work in groups. Your completed assignment is due on Wednesday 2/12, by noon.

Submit your assignment using this form. The form expects your visualization to be an image (either a .png or .jpg). Please make sure your image is sized for a reasonable viewing experience -- readers should not have to zoom or scroll in order to effectively view your submission!

Resubmissions. Resubmissions will be regraded by teaching staff, and you may earn back up to 50% of the points lost in the original submission. To resubmit this assignment, please use this form and follow the same submission process described above. Include a short 1 paragraph description summarizing the changes from the initial submission. Resubmissions without this summary will not be regraded. Resubmissions will be due by 11:59pm on Saturday, 2/29. Slack days may not be applied to extend the resubmission deadline. The teaching staff will only begin to regrade assignments once the Final Project phase begins, so please be patient.