Scatterplots

Nevada

A scatter plot is a graph used to visually examine the relationship between two quantitative variables that are plotted on the x- and y- axis, respectively. Points are plotted in relation to both variables, and from this a correlation can be determined.  A “line of best fit” can be used further in analysis of the relationship between variables.

A few types of correlation to look for include:

  • Positive correlation- upward, rising trend of data (positive slope)
  • Negative correlation- downward, decreasing trend of data (negative slope)
  • No correlation- scattered data with no obvious relationship

2007-11-16_120504

Further analysis on scatter plots and correlation can be found  here. However, correlation is not to be confused with causality. Supposing that a relationship exists, it cannot be proven one variable causes a change in the other variable. More on the avoidable pitfalls of scatter plots can be found at Sky Mark and at the Regents Exam Prep Website.

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3 comments

  1. Your first link is broken.

  2. Nice explanation with helpful graphics choice.

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