Question to test your Scatterplots & Intro to Correlation knowledge

Question

A biologist records rainfall and plant species counts for 10 regions, but the actual data values are not provided. She then adds an 11th region known to be an influential high-leverage point with unusually high rainfall, low species count, and alignment with a negative rainfall-species trend.
Using the randomization method, explain whether statistical significance can be determined from the information given, and describe qualitatively how the 11th region would likely affect the correlation coefficient and p-value.

Accepted Answer

The information provided in the problem is insufficient to apply the randomization method, so we cannot determine whether the evidence supports a linear correlation

The inclusion of the $11$ th region strengthens the evidence for a linear correlation (likely negative) between rainfall and species count

The added region decreases the correlation coefficient and lowers the $p$ -value

Answer

The information provided in the problem is sufficient to apply the randomization method.

The inclusion of the $11$ th region strengthens the evidence for a linear correlation (likely positive) between rainfall and species count

The added region decreases the correlation coefficient and raises the $p$ -value

Answer

The information provided in the problem is insufficient to apply the randomization method, so we cannot determine whether the evidence supports a linear correlation

The inclusion of the $11$ th region strengthens the evidence for a linear correlation (likely negative) between rainfall and species count

The added region reverses the direction of the correlation

Answer

The information provided in the problem is insufficient to apply the randomization method, so we cannot determine whether the evidence supports a linear correlation

The inclusion of the $11$ th region strengthens the evidence for a linear correlation (likely negative) between rainfall and species count

The added region reverses the direction of the correlation

Scatterplots & Intro to Correlation: Videos & Practice Problems