Logic of NHST using Pearson's r Flashcards
You obtain data on two variables (X & Y) for a sample of 6 people and calculate a Pearson’s r statistic from this data. Under the assumption that these variables are uncorrelated, the probability of obtaining a value of Pearson’s r of 0.82 or higher is:
a. less than 0.5%
b. between 0.5% and 1.0%
c. between 1.0% and 2.5%
d. between 2.5% and 5.0%
c. between 1.0% and 2.5%
You obtain data on two variables (X & Y) for a sample of 7 people and calculate a Pearson’s r statistic from this data. Under the assumption that these variables are uncorrelated, the probability of obtaining a value of Pearson’s r of -0.68 or less is:
a. less than 0.5%
b. between 0.5% and 1.0%
c. between 1.0% and 2.5%
d. between 2.5% and 5.0%
d. between 2.5% and 5.0%
You obtain data on two variables (X & Y) for a sample of 25 people and calculate a Pearson’s r statistic from this data. Under the assumption that these variables are uncorrelated, the probability of obtaining a value of Pearson’s r as extreme or more extreme than 0.48 (i.e. > 0.48 or < -0.48) is:
a. less than 1.0%
b. between 1.0% and 2.0%
c. between 2.0% and 5.0%
d. between 5% and 10%
b. between 1.0% and 2.0%
There is a positive correlation between variables X & Y
Is this a 1 or 2 tailed hypothesis?
1 tailed
There is a negative correlation between variables X & Y
Is this a 1 or 2 tailed hypothesis?
1 tailed
There is a correlation between variables X & Y
Is this a 1 or 2 tailed hypothesis?
2 tailed
What does it mean when p > 0.05 and we fail to reject the null in terms of Pearson’s r?
The r value is not sufficiently inconsistent with what I would expect randomly sampling from uncorrelated variables
What does it mean when p < 0.05 and we reject the null in terms of Pearson’s r?
It’s too unlikely that I would have got this value of r if sampling at random from uncorrelated variables
