Suppose a researcher is interested in how children respond to earthquakes. She collects a random sample of children aged 12 to 18 years who live within 25 miles of a known earthquake fault and asks them how many earthquakes they have felt in their lifetime. The researcher also collects other basic physical and demographic data, including height, weight, age, health status, education attained by each parent, and number of siblings.The researcher begins her exploratory analysis of the data by calculating the Pearson correlation coefficient (the zero-order correlations) between each pair of variables. She is surprised to find that the number of earthquakes ever felt is significantly correlated with the child's shoe size (r=0.74r=0.74).

Which of the following explanations are consistent with the number of earthquakes ever felt and the child's shoe size being positivelycorrelated? (Hint: Here you are looking for explanations that are consistent with the correlation, not necessarily the correct explanations.)Check all that apply.

-Children who have bigger feet are less sensitive and, therefore, less likely to feel an earthquake.

-Children who have bigger feet have more surface area touching the ground and, therefore, are more likely to feel an earthquake.

-Children who have bigger feet tend to be more active and are, therefore, less likely to be still when an earthquake hits. Thus, they are less likely to feel an earthquake.

-Children who have bigger feet tend to move around less and, therefore, are more likely to already be still when an earthquake hits. Thus, they are more likely to feel the earthquake.

The researcher believes this apparent relationship between the number of earthquakes ever felt and the child's shoe size may be spurious. She wonders whether a third variable is influencing both the number of earthquakes ever felt and the child's shoe size. The researcher believes this third variable might be age. She decides to calculate the partial correlation of the number of earthquakes ever felt and shoe size while controlling for age.Suppose the researcher assigns the following letters to each of the variables:X = shoe sizeY = number of earthquakes ever feltZ = ageShe calculates the following zero-order correlations:ryxryx= 0.740.74(correlation of shoe size and number of earthquakes ever felt)ryzryz= 0.840.84(correlation of number of earthquakes ever felt and age)rxzrxz= 0.860.86(correlation of age and shoe size)

The partial correlation of the number of earthquakes ever felt and shoe size while controlling for age is ryx.zryx.z= .OPTIONS: 0.74,0.30,0.02,0.06

The magnitude, or absolute value, of the zero-order correlation between the number of earthquakes ever felt and shoe size is MUCH LESS THAN, MUCH GREATER THAN, APPROXIMATELY THE SAME AS the magnitude of the partial correlation between the number of earthquakes ever felt and shoe size when controlling for age. This outcome suggests that age HAS LITTLE OR NO EFFECT ON OR CHANGES the relationship between the number of earthquakes ever felt and shoe size, supporting the notion that the relationship is DIRECT, INTERACTIVE, SPURIOUS OR INTERVENING .

Which of the following best explains why the number of earthquakes ever felt and the child's shoe size are positively correlated? (Hint: The correct choice does not assume correlation implies causation.)

-Children who have bigger feet tend to be more active and are, therefore, less likely to be still when an earthquake hits. Thus, they are less likely to feel an earthquake.

-Children who are older have experienced more earthquakes. Children who are older also typically have bigger feet.

-Children who have bigger feet tend to move around less and, therefore, are more likely to already be still when an earthquake hits. Thus, they are more likely to feel the earthquake.

-Children who have bigger feet are less sensitive and, therefore, less likely to feel an earthquake.