No correlation – All points are scattered and no best fit line could be drawnĬorrelation between height and weight of an individual can be found out using this data set:.

Negative correlation – the slope of the line is from right to left (falling) as the value of one variable increases, the value of other decreases.

Positive correlation – the slope of the line is from left to right (rising) as the value of one variable increases, the value of other also increases.

Closer the points to this line, stronger the correlation between the two variables. Unlike line graphs, here we get a scattered set of points which are used to get ‘best fit line’ or ‘trendline’. The use of scatter plots is when there is a huge data set and the requirement is to obtain the relationship between two variables, if any exists. It is also used in finding out the future trends by studying past data. Scatter plot is one of the seven basic tools used in quality control. Each point represents one data, showing the value of both the variables for that particular data.

The chart on which the dots are plotted is also called as a Dotogram.A scatter plot, also known as scatter chart, scatter diagram, or scattergraph, is a type of mathematical chart which displays a set of data, as a collection of individual points, using two variables on the two Cartesian coordinates. Thus, the scatter diagram method is the simplest device to study the degree of relationship between the variables by plotting the dots for each pair of variable values given. Here the correlation is absent and hence r = 0. No Correlation (r= 0): The variable is said to be unrelated when the points are haphazardly scattered over the graph and do not show any specific pattern.Low Degree of – Ve Correlation (r= + Low): The degree of correlation is low and negative when the points are scattered over the graph and the show the falling tendency from the upper left-hand corner to the lower right-hand corner.Low degree of +Ve Correlation (r= + Low): The correlation between the variables is said to be low but positive when the points are highly scattered over the graph and show a rising tendency from the lower left-hand corner to the upper right-hand corner.The variables on this scatter plot have no correlation with each other since the data is scattered in a general tendency with a zero slope, meaning, they do not. High Degree of –Ve Correlation (r= – High): The degree of negative correlation is high when the point plotted fall in the narrow band and show the declining tendency from the upper left-hand corner to the lower right-hand corner. Following the scatter plot definition and description we have learnt, we obtain the following scatter plot for the table above: Figure 3: Scatter plot for the data table in figure 2.High Degree of +Ve Correlation (r= + High): The degree of correlation is high when the points plotted fall under the narrow band and is said to be positive when these show the rising tendency from the lower left-hand corner to the upper right-hand corner.Perfect Negative Correlation (r=-1): When all the points lie on a straight line falling from the upper left-hand corner to the lower right-hand corner, the variables are said to be negatively correlated.Perfect Positive Correlation (r=+1): The correlation is said to be perfectly positive when all the points lie on the straight line rising from the lower left-hand corner to the upper right-hand corner.The following types of scatter diagrams tell about the degree of correlation between variable X and variable Y.

The degree of correlation is denoted by “r”. The more the points plotted are closer to the line, the higher is the degree of correlation.

The more the points plotted are scattered over the chart, the lesser is the degree of correlation between the variables. The degree to which the variables are related to each other depends on the manner in which the points are scattered over the chart.

Correlation scatter plot meaning