Key Features Vocabulary
Name the two measures we use to compare spread between two groups.
Range (max−min) and IQR (UQ−LQ).
What is the formula for IQR?
UQ − LQ
What percentage do we compare our tail proportion to?
All the students at the high school
What do we call the group that receives no treatment?
Control group
What is Ms Cheng's first name?
Emily
If the mean sits above the median, which direction is the data skewed?
Skewed to the right.
True or false: a bigger range always means a bigger IQR.
False
Same difference occurred 375/1000 times — what percentage?
37.5%
Give one way of avoiding bias in group allocation.
Random allocation (coin toss, random draw, etc.)
Which house has the most students in our class?
Hanrahan and Domitille
What do we call it when we point out an unusual value and try to explain why it's there?
An interesting point / interesting feature.
Two groups have medians of 83.5 and 83.5. What do you say about centre?
No difference — medians are identical.
If tail proportion > 10%, what do we conclude?
Likely due to chance alone.
What does it mean for an experiment to be "blind"?
Participants don't know which treatment they got.
Which country has appeared in the most FIFA World Cup tournaments?
Brazil (22 times, every World Cup since it began).
If each group's median falls inside the other group's box, what do we say about the two groups?
There is overlap — this suggests there may be no clear difference.
If Group 1's median sits just above Group 2's UQ, roughly what % of Group 2's data is below it?
75%
Why can't we just stop at the box plot. Why do we need re-randomisation?
Sample size too small for a reliable conclusion.
Which stages of PPDAC must be fully decided before you run the experiment on real participants?
Problem and Plan.
How many months have 28 days?
12