Full Mathematical PowerIn Calculated QuestionsThrough Spreadsheets.

1. Full Mathematical Power
In Calculated Questions
Through Spreadsheets
Moodle Research 2013
hiram.bollaert@ap.be @hiramglows

2. Context
• Artesis Plantijn University College Anwerp
• 1st year Professional Bachelors Business Studies
a very heterogeneous group
• Applied Statistics
– collaborate and peer teach live online.
– self-pacing, enabling faster students to advance and help
slower students
– spreadsheets to solve the exercises.
– gather learning content from the web.
 first line electronic tutor.
hiram.bollaert@ap.be @hiramglows

3. Calculated Questions in Moodle
• Example:
Calculate the area of a rectangle with a base of
{base}cm and a height of {height}cm.
• 3 parts:
– Wildcards: {base} & {height}
– Formula: {base} * {height}
– Data Set: {base} = 8 {height}=4
{base} = 2 {height}=7
{base} = 5 {height}=3
… …
hiram.bollaert@ap.be @hiramglows

4. Published Calculated Questions
• Moodle merges the question text with values from
the data set:
Calculate the area of a rectangle with a base of 8cm and a
height of 4cm.
• Moodle calculates the result using a given formula
and the published values:
Answer: 8 * 4 = 32
hiram.bollaert@ap.be @hiramglows

5. Very powerful, but…
• Moodle understands about 42 mathematical
functions ranging from “+” to “tanh”
• Limits?
we managed to get a 1171 characters long formula
with nine variables working generating an answer
that looks like
“4 years, 7 months and 15 days”
• But…
What if you would like to create formulas using
statistical functions?
hiram.bollaert@ap.be @hiramglows

6. Example: The Binomial Distribution
• Calculate the chance of more than 1 but less than 7
successes given there are 8 trials and the chance of
success is 18%.
• With a spreadsheet this is easily solved:
BINOMDIST(6 , 8 , 0.18 , true)-BINOMDIST(1 , 8, 0.18 , true)
hiram.bollaert@ap.be @hiramglows

7. The solution: Moodle XML
• Moodle allows EXPORT & IMPORT of XML files
• XML = eXtensible Markup Language = markup
language defining a set of rules for encoding
documents in a format that is both human-readable
and machine-readable.
<question type="calculated">
<name>
<text>bi_tires</text>
</name>
<questiontext format="html">
<text>Sample</text>
</questiontext>
hiram.bollaert@ap.be @hiramglows

8. Trick {answer}
• VBA: extract content from a spreadsheet and
translate into XML
• Introduce new wildcard {answer} and give it the
value calculated by a formula of your choice.
PROBLEM
You need to include [answer} in the question text!
(and use {answer} in the formula specified in the
definition of the calculated question)
hiram.bollaert@ap.be @hiramglows

9. • Hide:
You can use HTML tags in the question text and thus
hide text with comment tags
<!– hidden text -->
Be aware that hidden text is very visible in the page source
code
• Camouflage:
Place a random set of random numbers in before
and after the correct answer
Hide and Camouflage
hiram.bollaert@ap.be @hiramglows

10. Result
Expect that somebody will explore the page source
code.
And if this is not enough, there are more easy tricks to hide away the correct answer.
hiram.bollaert@ap.be @hiramglows

11. CQ4M Generator
• Download this spreadsheet from
https://sites.google.com/site/cq4mgenerator/
hiram.bollaert@ap.be @hiramglows

12. Regions
hiram.bollaert@ap.be @hiramglows
Calculation of
the correct
answer and
alternatives
Definition
and
preparation
of all used
variables
(wildcards)
Dataset:
All values for the
wildcards, answers are
multiplied with a
‘disguising’ factor
Camouflaging
Moodle Question Definition
Macro assigned buttons
Moodle Formula Definition

13. Steps
1. Question Name
2. Category Name
3. Question Text
4. Default Grade
5. Formulas
6. Wildcards
7. Preparation
8. Work Area
9. XML
hiram.bollaert@ap.be @hiramglows

14. • Google Group CQ4M Generator
https://groups.google.com/forum/#!forum/cq4m-
generator
• Google Site CQ4M Generator
https://sites.google.com/site/cq4mgenerator/
• Mail, Twitter
h.bollaert@gmail.com, @hiramglows
hiram.bollaert@ap.be @hiramglows
Comment! Share!

15. hiram.bollaert@ap.be @hiramglows
Thank you