Scatter graphs
A scatter graph has points that show the relationship between two sets of data. We can draw a line of best fit (also called a trend line) on this scatter plot. It may not join up all of the points on the graph, but it shows generally if the numbers in the data go up or down.
Correlation
If there is a correlation between two sets of data, that means they are connected in some way. When there is no correlations there is no connection between them, and this is represented with a scatter graph.
The types of data
Data can fit into two categories, qualitative and quantitative. Qualitative data can only be described in words, like the colour of cars in a car park. Quantitative data can only be shown with numbers, like the number of cars in a car park.
Quantitative has two categories, discrete and continuous. Discrete data cannot only take certain values. Continuous can take any value, but it needs to be measured.
Interpolation and extrapolation
Interpolation is where we find a value inside the set of data points on a graph. Extrapolation is where we find a value outside the set of data values on a graph. It can be found after drawing the line that connects all the points, or a line of best fit which can go on forever. But be careful: extrapolation is hard to work out and can give misleading results.
Non-linear relationships
A non-linear relationship is when two sets of data are connected, but doesn't necessarily mean that change in one means change in the other. This means the connection can be unpredictable.
Two-way tables
Two-way tables display frequencies for two different categories collected from the same group of data. One is represented by rows and the other by columns.
Frequency tables
The ungrouped frequency distribution is a type of frequency distribution that displays the frequency of each individual value, instead of groups of data. The grouped frequency table organises and simplifies larger sets of data to groups them in smaller chunks, thus making it easier to understand.
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Maths Revision
RandomMy funny and well-explained KS3 Maths Revision guide, derived from Bitesize. Still in progress, as I learn the nightmare called Maths by myself.
