Mean and Median vs Shape of Distribution

In a skewed distribution...

• data can only skew to the right

• mean = median

• Data points do not follow any pattern

• one side of the distribution has more values farther from the bulk of the data than the other side.

This data is...

• skewed to the right

• skewed to the left

• symmetrical

• bimodal

This data is...

• skewed to the right

• bimodal

• symmetrical

• uniform

Bimodal distributions...

• has two very common data values (peaks) seen in a dot plot or histogram

• are always symmetric

• mean = median

• may be skewed to the right of to the left

Make notes now on the shapes of distributions and how the mean, median and mode might predict the skew of a distribution. Page 180-181 in the Statistics GCSE book will help. Let me know you have completed this task by writing a message bekow,

It is useful to describe the shape of data. It can be symmetrical or have a positive or negative skew. Data with a positive skew has a long tail in the positive direction of the horizontal axis. Data with a negative skew has....

• a long tail in the direction of the negative horizontal access

• a long tail in the direction of the positive horizontal access

Box plots can display the skew of data. The position of the median relative to the quartiles describes the skew. Match the box plots to the correct graphs below

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A positive number means positive skew. Negative number means negative skew, What do you think 0 means?

• Very negatively skewed

• Moderate negative skew

• Symmetrical data

• Moderate positive skew

• Very positive skew

The data in the picture:

• is negatively skewed

• positively skewed

• symmetrical

The data in the picture:

• is negatively skewed

• positively skewed

• symmetrical