Plot two variables of hourly or daily data over a year. The scatterplot shows whether a relationship between two variables exists, the strength of that relationship, and its direction.

Open the map and choose a location. You must clear the current location before selecting a different one.
Central Park, NY
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Select two variables to see how the first affects the second.

The independent variable is represented on the X-axis. This is the variable that is presumed to be causing a change. The dependent variable is represented on the Y-axis.

The resulting correlations may be positive (dots rising from lower left to upper right), negative (falling from upper left to lower right), or neither (uncorrelated).

The trendline shows the correlation between the variables. You can then express this relationship in the form of an equation, which is a mathematical model of how the variables are related. The equation can help you estimate values on the X axis for which there are no actual data.
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