| Date | May 2016 | Marks available | 1 | Reference code | 16M.1.SL.tz0.27 |
| Level | Standard Level | Paper | Paper 1 | Time zone | time zone 0 |
| Command term | What | Question number | 27 | Adapted from | N/A |
Question
What does standard deviation represent?
A. The ratio of the correlation to the mean
B. A causal relationship between two variables
C. The correlation between two variables
D. It summarises the spread of values around the mean
Markscheme
D
Examiners report
An easy question, with A as the main distractor.
Syllabus sections
Topic 6: Measurement and evaluation of human performance » 6.1. Statistical analysis » 6.1.3. State that the statistic standard deviation is used to summarize the spread of values around the mean, and that within a normal distribution approximately 68% and 95% of the values fall within plus or minus one or two standard deviations respectively.
