Measures of central tendencies

• The central tendency is a number that tell us…

  where the middle of the distribution is.
• The central tendency tells us where the centre of the distribution is located.The dispersion tells us how spread out the distribution is.
• Define mode

  most frequently occurring value
• How do we describe distribution?

  Central tendency + dispersion
• The bigger the range, the more spread out data there is

  the smaller the range, the less spread out data there is
• What is the range?

  The measure of dispersion
• What is standard deviation?

  How spread out the data is from the mean.
• when is standard deviation used?

  • Best when you need to know if the data is consistent or varied.
  • Used in experiments to check how reliable the results are.
• What does a low SD show?

  Data is closer to the mean = more consistent results
• What does a high SD show?

  Data is spread out = less consistent results and have anomalies
• What is the mean?

  The average of all the scores.👉 Add up all the scores and divide by how many there are.
• When is the mean used?

  • Best when there are no extreme outliers (weird numbers that mess everything up).
  • Gives the most accurate average 🔥.
• what is the median?

  the middle number when all the data is in order.
• when is the median used?

  • Best when there are extreme outliers because it ignores them.
  • Gives a better central value when data is skewed.
• Strength of the mean

  Most accurate average because it uses all data points
• Limitation of the mean

  🚫 Can be distorted by outliers, making results misleading
• Strength of mode

  Easy to calculate + shows the most common category
• limitation of mode

  🚫 Not useful if there's more than one mode or no mode at all
• Strength of median

  ✅ Not affected by outliers, giving a more representative score
• limitation of median

  Does not consider all the data — ignores higher and lower scores
• Strength of standard deviation

  Gives a more detailed view of how consistent the data is
• limitation of standard deviation

  Harder to calculate + doesn't show extreme scores clearly
• when is the range used?

  Quick and easy way to see how spread out the data is👉 Best when you need a basic measure of dispersion
• strength of the range

  Super easy to calculate

  ✅ Gives a rough idea of spread

  ✅ Useful when data is consistent
• Limitation of range

  🚫 Only uses two numbers — ignores the rest of the data

  🚫 Doesn't show how spread out the data is (Standard Deviation is better for that)

  🚫 Gets wrecked by outliers 🔥 (like one really high or low score)