Chapter 3: Central Tendency and Variability
Answers for all ‘Test Yourself’ questions from the book to check your performance and widen your overall understanding of the contents.
- This data is positively skewed; the tail leads off to the right.
- a) Negatively skewed
- This could be pronounced in many ways. You might have picked any one of these, but they are all correct: “z is a deviation divided by the sample standard deviation” or “z is the difference between a score and the sample mean, divided by the sample standard deviation” or “z equals x minus x bar, all over s”.
- a) Ratio, Mean
b) Nominal, Mode
c) Ordinal, Median
- a) 5
- There are many ways to do this, but here are some possibilities:
“The centre of this dataset is 3.”
“The distance between the highest and lowest value is 20”