Final Grades

by Mike Gleicher on December 16, 2019

You cannot use Canvas to compute your final grades. It is set so that the Design Challenges and other meaningful parts of class “are not counted towards the final grade” – the things that were counted are things that shouldn’t.

Aditya and I agonized over grading for a while, since it was complicated. We computed the grades several different ways. We then went over each person individually to confirm the final grade.

What we did:

  1. There is an “adjusted online part” score – if you remember, I said that you can’t really excel for doing these parts. We combined seek and find and online discussion grades into a single score. There wasn’t too much variance in the class – so each person got an “AB” (but some people got “high ABs” and some got “low ABs”)
  2. There was a “subjective parts correction” – if you were chronically late, you were penalized (very few people). If you were really bad or good about online participation, or really bad/good with in class participation. This adjustment was about half of a grade step. (plus or minus). This was mainly a way to reward a few people for very exemplary participation.
  3. We tried many different formulas, all lead to very similar answers.

The simplest formula is to count “adjusted online part” (#1) and the design challenges equally, and then add in the “subjective parts correction”. We then shifted people upwards a bit. We did a few checks: to get an A, you should have gotten at least one A on a DC (probably 2), etc.

We had a few other ways to compute grades (a decision tree, some non-linear scalings, different weightings, …). They all gave very similar results. In the rare cases where they gave different answers, we looked closely at the differences and usually gave the higher grade.

All of this is consistent with the way grading was explained in the Course Policies and Parts of Class.

DC3 Grades

by Mike Gleicher on December 16, 2019

DC3 Feedback

You should get DC3 feedback soon on Canvas. This is for the final handin.

Grades – the letter grades sometimes have a +/-. A “AB-” means “an AB, but on the low side of AB” – it gets the same grade as an “AB +”, but we kept it in our notes so we can compare things for consistency.

The numbers are A=90, B=80, etc.

We had to grade very quickly, so we may have missed some of the good things in your assignment. To make up for this, we are adding 2 points to everyone’s assignment. (this is why the number posted on Canvas is two higher than what is posted in the explanation).

Because grading was done quickly, the comments we provide may not be that extensive.

Any assignment turned in by the time we started grading on Sunday morning was not penalized for being late. We thank everyone for being prompt with turning in assignments on time.

We categorized assignments into a few basic “types”. For each type, we had things we were looking for in a good assignment. These can give you an idea of what we were thinking.

  1. Single Standard design to show hierarchy (TreeMap, Sunburst, Tree)

    • suggested design
    • deals with overlap somehow
    • consider interactions (details, navigation)
    • actually shows hierachy (vs. level at a time, require interaction)
    • talks about tasks (potential use cases)
    • describes design in detail
    • rationale for details
    • rationale for high level choice (i.e., to use a colored treemap)
    • describes implementation details and how to run
    • extra bells and whistles
    • discussing findings (use case)
    • scalability discussion
  2. Multiple, task-specific designs integrated

    • multiple designs that work together in a system
    • each design is described
    • each design has tasks associated
    • use cases use designs
    • discusses rationale / encoding choices for each design
    • deals with category sharing questions
  3. Multiple Designs, Not-Integrated

    • multiple designs used independently
    • each design is well described
    • rationale for each design given and discussed
    • tasks for each
    • anti-tasks for each (to know when not to use each design – motivation for others)
    • Standard (suggested) vs. Non-Standard designs
  4. Single, Non-Standard (or semi-standard) Design

    • considers multiple tasks with one design
  5. Analysis of a Data Set Using Multiple Views

  6. Sketch of Multiple View System

    • rationale and task thinking must be really good to make up for lack of implementation
    • needs to consider multiple tasks thoroughly
    • needs to consider how different views work together to solve harder tasks
    • discuss encodings and designs and interactions
    • must show creativity in designs (not just standard views)

DC2 Grades

by Mike Gleicher on December 11, 2019

DC2 Grades were posted . These are for the final hand-ins only. They do not consider the earlier phases or lateness.

The scale is 90=A, 85=AB, etc.

Interpreting DC3 Data

by Mike Gleicher on December 9, 2019

I had two questions today about the DC3 Data.

First: the sub-tree totals don’t necessarily add up. This is intentional: the subtree count tries to avoid duplicates.

In other words, if you have category “parent”, “child1” and “child2”, parent.subtreeProductCount <= child1 + child2 (because there might be some products that are in both child1 and child2). As far as I know, the code computes this correctly.

Second: for the “small” data sets, the root nodes may have incorrect counts. There is a bug in the code that only affects the root (the first line in the file), and only for the subtree data sets. If you really need the numbers for those nodes, you can look them up in the “all-nodes” file.


The Week in Vis 15 (Mon, Dec 9 – Fri, Dec 13): SciVis

by Mike Gleicher on December 6, 2019

Week in Vis 15 Mon, Dec 9-Fri, Dec 13

Please do a course evaluation! ( It really does help me! (and it will help future students in the class)

We’ve made it to the last week. You’re probably focused on DC3, but we’ll have 2 last things to do in class. On Monday, I’ll talk about “scientific visualization” – which is a huge set of topics that probably could be a separate course. I just don’t feel like you can have a vis class without discussing them at all. On Wednesday, we’ll have one last ICE – that we’ll use as a way to reflect on everything we’ve done this semester.

Beyond this week… if you are interested in doing more Vis stuff, talk to me. There are opportunities for projects in the future.

Readings for the Week

For Scientific Visualization, there is nothing I know of that is at the right level of detail. The chapter from Munzner will give you some of the basic concepts. But, this late in the class, you’re probably burned out from reading anyway.


This is the closest thing I can find to a survey paper about volume rendering (which is probably the most common case). The front parts cover the basics, but it quickly gets into more detail than you probably want.

  • Arie Kaufman and Klaus Mueller. Overview of Volume Rendering. Chapter 7 of The Visualization Handbook (Hansen and Johnson eds), Academic Press, 2005. (chapter7-volumerendering.pdf 0.7mb)

Course Evals

by Mike Gleicher on December 5, 2019

It’s time for Course Evaluations.

These are being done online (go to

I really do look at these things and use them to plan and improve the class. They really do help me.

Week in Vis 14 Mon, Dec 2-Fri, Dec 6

On Monday, I’ll give a presentation about how to give presentations. Historically, this has been me ranting – I’ll try to be a bit more organized this year. Student have told me this is useful – since giving presentations is something everyone has to do, but you might not get much “training” in. I’ll probably also talk a little bit about Graphic Design – we aren’t going to cover the topic this year, but I feel like I should say something about it.

On Wednesday, we’ll do an ICE to get you thinking about design a bit more.

The readings this week are intentionally light. I know you’re focused on DC3. Not much to turn in, but the end of the semester is coming along fast…

Readings for the Week

The “readings” for this week are to watch 2 videos, and to look over my notes on presentations. The notes are likely redundant with what I’ll present in class, but they have some resources and details. But make sure to watch the videos.

Before reading my notes, here are some caveats (note: this is taken from the 2012 class):

  • The goals and standard for presentation really vary across venue/discipline. What we value in computer science (in particular the areas I work in) are quite different than in other disciplines. It’s hard for me to discuss this without value judgement (since I am bred to believe in the “CS way”), but I also plead ignorance to the practices in other area. I’d like to use this as a chance to learn about others.
  • I don’t consider myself to be a great presenter. Do as I say, not as I do. The upside of this, is that it means I think about how to be better at it.
  • A lecture is not the same as a talk, so what you see in class is quite different than what you would see in one of my talks.
  • Even within a particular style/venue/type of talk, there is a wide range of opinions on what is good talk, what the goals should be, …
  • The “right answer” depends not only on the situation, but on the person. But that will be one of the biggest lessons I hope you get. I may not speak to your specific case, but hopefully, you can see how the general lessons apply.
  • As you might guess, I have strong opinions. But you don’t have to guess at what they are, since I’ve written them down.

Given that…

My real goal is to get you to think about what might make for a good presentation, and to form your own strong opinions – even if they are different than mine.

Given that, read my posting about presentations. Yes, it’s from a 2011 class – but I think if I were updating it, it wouldn’t be much different.

Video Presentations

Hans Rosling is a famous presenter – talking about social issues around the world in venues like TED, etc. He was famous for presenting data in a compelling way to make his points for a broad audience. Sadly, he died this year. But his influence is significant (both on presentating data and on the world in general).

If you haven’t seen a Rosling talk, you need to experience one. If you have seen one, you probably won’t mind watching another.

There are lots of videos of rosling presentations – here’s one I have handy, or here’s another one.

The actual point of Rosling is not his visualizations (he does use standard visualization effectively – often with animation), but rather as a way to talk about presentations.


Rather than read about animation, I’ll let you watch a (reasonably old video) about it’s role in visualization.

I’ll kill two birds with one stone here: I want you to think about the role of animations in visualization, and how to present research results in video form. So, I’ll have you watch a research video about animation in visualization!

You don’t have to read the paper, but you do have to watch the video:

  • Heer, Jeffrey, and George Robertson. “Animated Transitions in Statistical Data Graphics.” IEEE Transactions on Visualization and Computer Graphics 13, no. 6 (January 2007): 1240–47. doi:10.1109/TVCG.2007.70539. (web page with video)

Some of the ideas in the video have been questioned in perceptual studies, but I think the basic concepts are still worthwhile.

The Week in Vis 13 (Mon, Nov 25 – Fri, Nov 29): 3D

by Mike Gleicher on November 22, 2019

Week in Vis 13 Mon, Nov 25-Fri, Nov 29

It’s Thanksgiving already. We will have class on Wednesday.

Hopefully, you are starting Design Challenge 3. If you have not yet found a partner (but would like to work with a partner), please stay around after class on Monday. There were enough people looking for partners on Wednesday that you should be able to find someone. It’s OK if you tell us your partner on Monday. (but please post on Canvas with your partner, or whether you are working along, by Monday). For this week’s design challenge component, we would like to have some evidence that you’re thinking about the problem. Just post something.

The topic for lecture this week is 3D. We’ve avoided the topic for the whole semester. We’ll talk about how we “see 3D”, and some of the things this might mean for making visualizations in 3D. We won’t get to talk about graphics programming much (that’s another class), and we’ll talk about specific kinds of 3D visualization (like Volumes) when we get to Scientific Visualization.

For the ICE, we’ll probably look at some things from design challenges. Or we’ll try some other design thing.

Readings for the Week

It’s hard to know where to start to talk about 3D. But for required readings, we’ll focus on the perceptual issues.


More resources on these topics are on the readings page from 2017. All of the links should work for you, except for the Illustration handbook (which may be my favorite):

This is a chapter of the “Guild Handbook of Illustration” that helps illustrators learn to convey 3D shape in their drawings. A lot of it is about how to think about how light helps you perceive shape (and it does so with fabulous examples). When they start talking about the actual techniques (like how to use charcoal to make the pictures), it’s a little less interesting.

DC1 Peer Review Feedback / Grades

by Mike Gleicher on November 18, 2019

Peer Critique Score Sheet

20pts total (since this is 20% of the DC1 grade)

  • 5 pts – Did all 3 reviews correctly
  • 5 pts per critique
    • 5 – Great critique. Has all required parts (acknowledgments, specifics connected to principles). Commits no bad practices. Offers interesting insight or multiple insights.
    • 4 – Good critique. Has all required parts (acknowledgments, specifics connected to principles). Commits no bad practices.
    • 3 – Marginal Critique. Missing a required part, or commits bad practices.
    • 2 – Poor critique. Multiple problems (missing parts, multiple bad practices, …)
    • 1 – Unacceptable critique – we couldn’t even show this to the author.

Parts of a critique:

  • Provides an overall statement that shows that acknowledges the design.
  • Provides at least 1 specific detail and connects it to principle
  • Avoids bad critique practice
    • prescriptive without backing up with principle and reason
    • prescriptive suggesting the author do something that might address a different question
    • poorly phrased prescription
    • critique of the author
    • incorrect use of a principle (e.g. suggesting use of non-ordered encoding for an ordinal variable)
  • bonus for insightful comment or thorough criticism

Generally, good critiques get a 4. You get a 3 if something is missing, or a 5 if you do something exceptional. For each critique. In grading, rather than write down each reason speficially, we used the following standard codes:

Reason Codes (generally things that are missing – causes why you didn’t get a 4):
– Z – prescribes without goal and/or incomplete reasoning
– Y – negative comment without principle to back it up
– X – Non-specific acknowledgment (or no acknowledgment of design/goal)
– W – unfounded (or unsupported) assertion
– V – Specific change not connected to reason.
– U – No specifics.
– T – Gives alternative design without motivation.
– S – Negative not connected to goal
– R – “Is not the best. X is better.” (mixes in T,W,Y)
– Q – Questioning the authors motivation

Reason Codes (things that are good and push your score up)

A – Extensive acknowledgment
B – Extra-thorough reasoning
C – Many good detail points

It works out that if you get a 4 on each, you get 17/20 which is 85% or an AB. We don’t always write all applicable codes.

Some specific examples:

Provides an overall statement that shows that acknowledges the design:
Good: The task for this visualization is to present trends among average household income with two separate education measurements – % of adults with bachelor’s degrees or higher and % of adults with some college or associate’s degree. Specifically, the visualization raises the question if bachelor’s degrees tend to lead to higher income than just an associate’s degree.
Not Good: The design has presented the data in a very informative manner. Awesome!

Provides a specific Detail and connects it to principle:
Good: If the goal was to more directly compare the scatter plots and trend lines for the two separate education levels, then it would have been better to have the two education levels on the same scale. The bachelor’s degree attainment scale ranges from 0 to 55% while the associate’s degree scale ranges from 0 to 40%. This makes it easier for the viewer to draw incorrect conclusions from the visualization.
Less Good (only detail, no principle): One suggestion is that maybe it can change the representation of average line as it is a little distractive for me.
Bad (prescribes, without giving principle or rationale): If the purpose is to show the relationship of the factors with respect to months, it would have been better to use discrete variables for months.

Acknowledges the design thoroughly:
Good: The design shows the relation among birth rate, death rate and numeric change in resident total population in 2015 for a few states in the United States. It contains two overlapped plots: stacked area chart to show birth and death rates, and bar chart to show numeric change in resident total population. They are good choices although both stacked line chart and grouped bar chart could be options for the former one. And I understand stacked area chart as a variation of stacked line chart, and it is good at emphasizing the difference between two sets of points (i.e. birth rates and death rates for several states in this case). The bar chart shows negative numbers below x-axis, which is great to highlight negative cases. Three variables are color encoded and length encoded (i.e. height of the bar), and they all contribute to a clear story. Also, states are sorted alphabetically, which makes the viewer locate a state effortlessly.

Design Challenge 3 has been posted!

by Mike Gleicher on November 18, 2019

Design challenge 3 has been posted. Check here.

Please read through it and bring questions to class on Wednesday, November 20th. If you have a question about the assignment, please ask in class – someone else probably has a similar question. (if you want to ask by email, I may answer in class)

For this week, we want people to choose partners. Working with a partner is optional, but encouraged. We will help you find a partner if you want one.