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Water and Carbon Cycles

Measures of Central Tendency and Dispersion

  • 4 things to know
  • Component 1

Overview

Recall questions on the mean, mode and median as measures of central tendency, on range, inter-quartile range and standard deviation as measures of dispersion, and on reading, using and the limitations of dispersion diagrams.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

Define the mean as a measure of central tendency.

Key term

What is central tendency in statistics?

Key term

What does standard deviation measure?

Process

Define the mode, the median and the range.

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    Define the mean as a measure of central tendency.

    Model answer

    The sum of all values divided by the number of values in the data set.

  2. 2

    Define the mode as a measure of central tendency.

    Model answer

    The most frequently occurring value in a data set.

  3. 3

    Define the median as a measure of central tendency.

    Model answer

    The middle value when all values are arranged in rank order.

  4. 4

    What is central tendency in statistics?

    Model answer

    A single value that represents the typical or central value of a data set.

  5. 5

    Define range as a measure of dispersion.

    Model answer

    The difference between the highest and lowest values in a data set.

  6. 6

    What is the inter-quartile range?

    Model answer

    The difference between the upper quartile (75th percentile) and lower quartile (25th percentile), representing the spread of the middle 50% of data.

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