Scatter Plot
Definition
A two-dimensional graph in which each observation is plotted as a point at coordinates (x, y), where x and y are two measured variables. Used to detect correlation, clustering, and anomalies in paired measurements.
- Axes
- Two measured variables, x and y
- Unit of display
- One point per observation
- Detects
- Correlation, clustering, outliers
- Field
- Forensic data visualisation
Common questions
What kind of forensic question suits a scatter plot?+
Any question about the relationship between two continuous measurements, such as plotting bloodstain drop diameter against fall height, or comparing two chemical concentrations across a batch of drug samples, to see if they move together.
What limits does a scatter plot have with forensic data?+
It shows only two variables at a time, so relationships involving three or more factors, or effects hidden by overlapping points in large datasets, need additional techniques such as colour coding, jittering, or multivariate plots.
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- Kernel Density Estimate (KDE)
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