# Maths unit 3&4

 Types of data Categorical: Ordinal, nominalNumerical: Discrete, continuous Categorical A category is recorded when the data is collected. Numerical When data is collected a number is recorded. There are two typesDiscrete: The numbers are distinct values, often whole numbers and usually the data comess from counting.Continuous: Any number on a continuous number line is recoded; usally the data is produced by measuring to any desired level of accuracy. Bar chart Categorical data Mode The most frequently occuring value or category. Segmented bar chart & Percentage segmented bar chart Categorical data Histogram Continuous dataColumns are joined together Column graph Discrete dataEqual width with spaces between Symmetrical Same shape either side of the centre Positively skewed Tails off to the right Negatively skewed Tails off to the right Outliers Extreme values, well away from the majority of data, should be considered. Range largest value - smallest value Stemplot discrete data Median O2The middle value when the data is ordered(n+1/2) The interquartile range IQRQ3 - Q1Q3= the midpoint of the upper halfQ1= the midpoint of the lower half Box plot MinimumQ1medianQ3maximum Mean ẋThe averagemean= sum of data values/ total number of data values 68% one standard deviation of the mean 95% two sd of the mean 98% three sd of the mean Authorbridgit ID66966 Card SetMaths unit 3&4 Descriptionstudy notes for further maths units 3&4 Updated2011-02-17T09:54:06Z Show Answers