data analysis: descriptive statistics Flashcards
What are descriptive statistics?
Are used to summarise and analyse quantitative data in order to draw conclusions
What are measures of central tendency?
General term for any measure of the average value in a set of data ( mean , mode and median)
What is the mean?
Arithmetic average
- done by adding up all the numbers & dividing by how many there are
What are the strengths of the mean?
- includes all score which is the most sensitive and most representative
What are the weaknesses of the mean
easily distorted by extreme values
What is the mode?
most frequently occurring value
What are the strengths of the mode?
easy to calculate
What are the weaknesses of the mode
not very representative as a whole
What is the median?
central value when values are arranged from lowest to highest
What are the strengths of the median
- not affected by extreme scores
- easy to calculate
What are the weaknesses of the median
- less sensitive than the mean which means it doesn’t use all the data
What are measures of dispersion?
any measure of the spread or variation in a set of scores
What is the range?
highest and lowest number subtracted
What are the strengths of the range?
- easy to calculate
What are the weaknesses of the range?
only considers 2 extreme scores which is unrepresentative of the spread of scores
