The scatter plot below shows the average traffic volume and average vehicle speed on a certain freeway for 50 days in 1999.

Explain the relationship/correlation you notice on the graph - positive or negative; linear or nonlinear; strong or weak

1 answer

Without seeing the scatter plot, I can provide a general explanation based on typical relationships between average traffic volume and average vehicle speed.

  1. Type of Correlation: Generally, you might observe a negative correlation between average traffic volume and average vehicle speed. As the volume of vehicles on the freeway increases, the average speed tends to decrease due to congestion.

  2. Linear vs. Nonlinear: The relationship could appear linear if the data points form a straight line when plotted. However, it may also appear nonlinear, showing a curve that illustrates more complexity in the relationship, such as speed decreasing at a certain point of volume increase.

  3. Strength of Correlation: If the points are tightly clustered around a line (whether straight or curved), it would indicate a strong correlation, meaning that changes in traffic volume reliably correspond to changes in vehicle speed. Conversely, if the points are widely scattered, the correlation would be described as weak.

In summary, if we follow the common trend, you might describe the correlation as negative and possibly linear, depending on the plot's specifics, and assess the strength based on how closely the data points cluster around the trend line.