Difficult positive vs negative correlation question

[BrownEMS]

Experiment 1:
A researcher conducts an experiment to study reflex times and the integration of several sensory processes. In the study, participants have to catch a ball that has been dropped. As an approximation for reflex "speed", researchers measure how far the ball falls before the participant catches it. The data in Table 1 is obtained:
Participant

7. What can be concluded from this data:

A. Reaction time is positively correlated with age and positively correlated with trial number.
B. Reaction time is positively correlated with age and negative correlated with trial number
C. Reaction time is negatively correlated with age and positively correlated with attempt number.
D. Reaction time is negatively correlated with age and negatively correlated with attempt number.

I don't know the answer, and find myself getting confused.



My instructor says the answer is D, but I'm pretty sure it is the exact opposite. Can you explain what your answer choice is?

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[MedHopeful20134]

I got D, but don't be discouraged!

I would suggest re-reading the definition of positive versus negative correlation.

First, compare age with reaction time. Then, attempt number with reaction time.

 

[BrownEMS]

I got D, but don't be discouraged!

I would suggest re-reading the definition of positive versus negative correlation.

First, compare age with reaction time. Then, attempt number with reaction time.

Thanks, but I am still confused. The higher the cm value, the lower the reaction time, right?

Let's take a look:

↑ cm (↓ reaction time) corresponds with ↓ trial number and ↓ age -- the lower the trial number and the lower the age, the higher the cm value.

When you compare reaction time (not cm) with trial number and age, you see that as reaction time decreases, trial # and age also decreases. Isn't this a positive correlation?

 

[IWillMakeIt1]

The ages aren't in order, make sure they are in order.


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[Coltuna]

I remember this question in my Kaplan course I think lol. A higher centimeter value corresponds to a higher reaction reation time. If you look as age INCREASES, reaction time DECREASES aka distance before reacting decreases. As subsequent trial number INCREASES, reaction time DECREASES. Because these relationships are opposite it's a negative correlation. If reaction time increased as age and attempt number increased, it would be a positive correlation. Remember that greater correlation is closer to 1 OR -1.

 

[Ad2b]

Old people do things better than young people. Next?

Okay, for real; easiest way to interpret graphs, to me, is to take 2 things that are most alike and then compare the others to them

Age goes up, reaction time also goes down (30 year old caught the ball at shorter distance than the younger peeps)

as age goes down (negative), trial goes down (negative): D

 

[DaAlienist]

Experiment 1:
A researcher conducts an experiment to study reflex times and the integration of several sensory processes. In the study, participants have to catch a ball that has been dropped. As an approximation for reflex "speed", researchers measure how far the ball falls before the participant catches it. The data in Table 1 is obtained:
Participant

7. What can be concluded from this data:

A. Reaction time is positively correlated with age and positively correlated with trial number.
B. Reaction time is positively correlated with age and negative correlated with trial number
C. Reaction time is negatively correlated with age and positively correlated with attempt number.
D. Reaction time is negatively correlated with age and negatively correlated with attempt number.

I don't know the answer, and find myself getting confused.



My instructor says the answer is D, but I'm pretty sure it is the exact opposite. Can you explain what your answer choice is?

The ball falls a shorter distance as they repeat the task, so they are getting quicker at catching the more the trials proceed (negative correlation between Trial # and reaction time). I got rid of A/C right then. As for the age, the table deliberately puts them out of order but if I arrange it 21-24-25-30 their times are 13.9-13.6-13.3-13.2 which again shows that as age goes up, the reaction time drops, another negative correlation.