Concluding – looking for patterns

Looking for patterns, trends and correlations in graphs

In this part of the paper, you will have to analyse your data and suggest or confirm a relationship between the independent variable (A), and the dependent variable (B). Here are some examples of relationships from graphs.

No correlation between variables A and B.

Variable A changes, B doesn’t change.

Variable B is independent of variable A.

A graph with the x axis labelled A and the y axis labelled B. A line runs horizontally from the y axis.

Direct proportion between A and B.

A changes, B changes in the same ratio, eg if A doubles, so does B.

A graph that shows direct proportion is a straight rising line that goes through the origin.

An example of this might be if A is the resultant force on a dynamics trolley and B is the acceleration of the trolley. The acceleration of the trolley is directly proportional to the resultant force.

A graph with the x axis labelled A and the y axis labelled B. A line runs upwards diagonally from the origin.

A and B are proportional to each other.

Variable A changes by a regular amount and so does B.

The graph does not go through the origin.

An example of this might be if A is a weight added to a spring and B is the length of the spring. The length of the spring is proportional to the weight added to it.

A graph with the x axis labelled A and the y axis labelled B. A line runs upwards diagonally from a point on the y axis.

There is an increasing positive correlation between variables A and B.

A increases by a regular amount.

B increases at an increasing rate.

A graph with the x axis labelled A and the y axis labelled B. A curved line runs horizontally from the origin and rises upwards.

There is a decreasing positive correlation between variables A and B.

A increases by a regular amount.

B increases at a decreasing rate.

A graph with the x axis labelled A and the y axis labelled B. A curved line runs vertically from the origin and then flattens.

Variables A and B show negative correlation to each other.

A increases by a regular amount.

B decreases by a regular amount.

A graph with the x axis labelled A and the y axis labelled B. A line runs downwards diagonally from the y axis to the x axis.

Variables A and B are inversely proportional to each other.

As A increases, B decreases.

As A doubles, B halves.

An example of this might be if A was the mass of a dynamics trolley and B was its acceleration. The acceleration of the trolley is inversely proportional to the mass of the trolley.

A graph with the x axis labelled A and the y axis labelled B. A concave curved line runs vertically from B to A.