Correlation Analysis Flashcards
What is the goal of correlational analysis in scientific research?
To determine if there is a relationship between two or more variables.
How does correlational analysis differ from other statistical analyses?
Variables are observed in their natural state rather than being manipulated.
What does a correlational analysis measure?
How two quantitative variables are related.
What do researchers look for when plotting data in a correlational analysis?
If there is a linear or curvilinear relationship.
What is the importance of calculating the strength of the relationship in correlational analysis?
To determine if there is a statistically significant relationship.
True or False: Correlation implies causation.
False
What defines a positive correlation?
Both variables increase together.
What defines a negative correlation?
As one variable increases, the other decreases.
What happens on a scatterplot when there is no correlation?
Points are spread out and do not resemble a specific line.
What is the correlation coefficient represented by Pearson’s r?
A statistic that indicates the degree and direction of the relationship between two variables.
What is the range of values for Pearson’s r?
- -1: Perfectly negative correlation
- 0: No correlation
- +1: Perfectly positive correlation
What does an r-value of -0.62 indicate?
Moderate, negative correlation.
What is the impact of outliers on correlation coefficients?
They can strongly impact the correlation coefficient in one direction or another.
What type of data does Spearman’s ρ (rho) analyze?
Ordinal data or non-normal continuous data.
True or False: Pearson’s r is used for nonparametric tests.
False
What does a strong positive correlation indicate?
As the values of X increase, so do the values of Y.
What is the definition of covariance?
The direction of the linear relationship between two variables.
Fill in the blank: A _______ relationship exists when the plotted ordered pairs approximate a straight line.
linear
What is a curvilinear relationship?
When the relationship between two variables does not follow a linear pattern.
What does a correlation coefficient less than r = -0.5 or greater than r = +0.5 indicate?
A potential relationship between two variables.
What is one limitation of correlational studies?
They cannot verify a cause-and-effect relationship.
What is a common method to visually represent correlations?
Scatterplots.
What is the role of the independent variable in a correlational analysis?
It explains changes in the dependent variable.
What is the significance of the correlation coefficient in a dataset?
It indicates the degree of relationship or consistency between variables.
