1. For each of the following, indicate whether you would expect a positive or a negative correlation. a. Height and weight for a group of adults b. Daily high temperature and daily energy consumption for 30 days in the March. c. Daily high temperature and daily energy consumption for 30 days in the December.
Correlation
Correlation defines a relationship between two independent variables. It tells the degree to which variables move in relation to each other. When two sets of data are related to each other, there is a correlation between them.
Linear Correlation
A correlation is used to determine the relationships between numerical and categorical variables. In other words, it is an indicator of how things are connected to one another. The correlation analysis is the study of how variables are related.
Regression Analysis
Regression analysis is a statistical method in which it estimates the relationship between a dependent variable and one or more independent variable. In simple terms dependent variable is called as outcome variable and independent variable is called as predictors. Regression analysis is one of the methods to find the trends in data. The independent variable used in Regression analysis is named Predictor variable. It offers data of an associated dependent variable regarding a particular outcome.
1. For each of the following, indicate whether you would expect a positive or a negative
a. Height and weight for a group of adults
b. Daily high temperature and daily energy consumption for 30 days in the March.
c. Daily high temperature and daily energy consumption for 30 days in the December.
2. The data points would be clustered more closely around a straight line for a correlation of – 0.80 than for a correlation of +0.05. (True or False?)
3. If the data points are tightly clustered around a line that slopes down from left to right, then a good estimate of the correlation would be +0.90. (True or False?)
4. As sample size gets smaller, what happens to the magnitude of the correlation necessary for significance? Explain why this occurs.
5. Describe what is measured by Spearman correlation, and explain how this correlation is different from the Pearson correlation.
6. Identify the two procedures that can be used to compute the Spearman correlation.
7. A correlation can never be greater than +1.00 (True or False?)
8. Describe what is measured by Pearson Correlation.
9. Compute the Spearman correlation for the following set of scores,
x y
2
12
9
10 7
38
6
19
Salary
More Than Php40,000 Salary
Less Than Php40,000
2
12
9
10 7
38
6
19
10. The following data represent job-related stress scores for a sample of n=8 individuals. These people also are classified by salary level.
a. Convert the data into a form suitable for the point-biserial correlation
b. compute the point-biserial correlation for these data.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps
