20 key chains: 0.4x=50. Since they are parallel
Answer:
The researcher should use correlation analysis for his studies.
Step-by-step explanation:
What is correlation?
Correlation is a statistical tool used to quantify the degree to which two variables are related. Through the correlation analysis, you evaluate correlation coefficient that tells you how much one variable changes when the other one does. Correlation analysis provides you with a linear relationship between two.
Types of correlation
1. Positive, Negative or Zero Correlation:
2. Linear or Curvilinear Correlation:
3. Scatter Diagram Method:
4. Pearson's Product Moment
Coefficient of Correlation:
5. Spearman's Rank Correlation
Coefficient:
