data analysis

What is normal distribution?

A symmetrical spread of frequency data

What type of shape does a normal distribution form on a graph?

Bell-shaped curve

Where is the mode, median and mean on a normal distribution graph?

Mode, median and mean are all at the same point at the centre

What does the distribution of a positive skew look like on a graph?

Distribution is concentrated on the left side of the graph

What could be the reason for a positive skew?

Caused by a difficult task, but a handful of people did well

What happens to the central tendencies of a positively skewed graph?

Mean, mode and median are lower

What does the distribution of a negative skew look like on a graph?

Most of the distribution is concentrated on the right

What could be the reason for a negative skew?

Could be caused by an easy task, but a handful of people do not do well

What happens to the central tendencies of a negatively skewed graph?

Mean, mode and median are higher

How are the mode, median and mean positively skewed?

mean > median > mode

How are the mode, median and mean negatively skewed?

mean < median < mode

What are the two measures of dispersion?

Range

Standard deviation

What is standard deviation?

How spread out the data is from the mean

When is bar chart used?

When data is divided into categories/discrete data

When is a histogram used?

When data is continuous

When is a line graph used?

When there is continuous data and a change over time