“Visual Analysis of Variance (ANOVA)”
Visual Analysis of Variance (ANOVA)
Jul 20, 2002
- Visual ANOVA is an interactive Flash program which demonstrates visually how
variability between and within experimental groups contributes to the F ratio in
the Analysis of Variance. It is not a numerical calculator; rather it visually
and holistically demostrates the relations among important concepts. Visual
ANOVA is supported by online instructions and by an extensive online lecture
explaining the theory behind the Analysis of Variance. The online lecture is
supported by two types of assignments: 1) Online computer-graded homework, and
2) A pdf file that gives students the opportunity to do handwritten homework
problems with answer keys.
- Type of Material:
- Flash program.
- Recommended Uses:
- After finishing a section of ANOVA, this too is an eye-opener fro students as it
distills all the complex mathematics into an interactive visualization. While
not appropriate for doing statistical analysis, it provides a further intutive
grasp of ANOVA.
- Technical Requirements:
- Flash plug-in.
- Identify Major Learning Goals:
- To increase understanding of ANOVA by supplementing with a visual interactive
interface, to allow the learner to move back and forth between textual,
mathematical, and visual representation of ANOVA.
To extend the lerner's understanding of variance and hypothesis testing with an
- Target Student Population:
- College and University students of beginning statistics and a refresher for
graduate students in statistical concepts.
- Prerequisite Knowledge or Skills:
- Understanding of basic statistics including means, variance, and hypothesis
- Content is clear and accessible. A few moves of the mouse and complex
statistical concepts are visually displayed. While the module does not claim to
be mathematically accurate, it is very sufficient to convey the concepts of
mean, variance, within and between sums of squares and the f ratio.
- Students may try to use the program before a reasonable understanding of ANOVA
and the assumptions such as homogeneity of variance.
- An amazingly efective tool to make mathematical concepts clear and
- Some initial confusion as to what the "red jelly beans" mean. But quickly
resolved with user interaction.
- Very easy to use both for teachers and students. A simple demonstration will
suffice to provide students with the understanding to carry out several problems
and may even be used in quizzes and exams using screen captures.
- Some old browsers may not be capable of using flash and some students may be
averse to installing the flash plug-in to a new browser. Most modern browsers
will have flash installed to mitigate this problem.
- Other Issues and Comments:
- It would be easy to imagine the "red jellybeans" could be redrawn as
distributions with normal shape distributions. The author is to be commended
for not doing this as the characterization is truly a model and s a teaching
tool should be presented as such. This is a program that one of the peer
reviewers had been teaching research methods with and found it to be engaging
and enlightening even after 25 years of teaching.
- Creative Commons: