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# Correlation

### What is the relationship between the sign of the correlation coefficient and the sign of the slope of the regression line?

A. What is the relationship between the sign of the correlation coefficient and the sign of the slope of the regression line? b. As the value of the correlation coefficient increases from 0 to 1, or decreases from 0 to -1, how do the points of the scatter plot fit the regression line? c. In your own words, state the prim

### Does correlation equal causation?

I am not understanding how to do this question as I am still trying to grasp an understanding of the material. I came across these questions at the end of the chapter: 1) Does correlation equal causation? Why or why not? 2). What is the relationship between correlation and association?

### Statistics: Correlation Analysis and Coefficient

(a) How does correlation analysis differ from regression analysis? (b) What does a correlation coefficient reveal? (c) State the quick rule for a significant correlation and explain its limitations. (d) What sums are needed to calculate a correlation coefficient? (e) What are the two ways of testing a correlation coefficient

### Computing Sample Correlation Coefficients

A popular, nationwide standardized test taken by high-school juniors and seniors may or may not measure academic potential, but we can nonetheless examine the relationship between scores on this test and performance in college. We have chosen a random sample of fifteen students just finishing their first year of college, and

### Scatter diagram, covariance, correlation, weighted average

45. Nielsen Media Research provides two measures of the television viewing audience: a television program rating, which is the percentage of households with televisions watching a program, and a television program share, which is the percentage of households watching a program among those with televisions in use. The following d

### Determining Correlation of Datasets

Can you provide an example using your own data set (two related and unrelated variables) of at least twenty numbers each and apply the formula of correlation. Determine the correlation of each of the two sets of data. Is the correlation positive or negative? Can you explain what this means? Can you explain the difference bet

### Correlation and Causation and Association

1) Does correlation equal causation? Why or why not? 2). What is the relationship between correlation and association? Please provide detailed explanation.

### Regression, Correlation and Variables

1. Does the strength of the correlation depend on the direction of the correlation ( + or -)? 2. How does linear regression relate to straight lines in algebra (slope, y-intercept, x and y)? 3. In regression, x predicts y. Does x cause y to happen? 4. What is the difference between the independent and dependent variabl

### Inferential Statistics and Linear Correlation

A study was conducted with alpha = 0.05 to determine if there is a significant linear correlation between the number of credit hours earned at the time of taking statistics 101 and the grade in the course. Eight pairs of data were collected. The linear correlation coefficient is y = 0.6777 Pick the correct answer a. T

### Calculate the correlation coefficient

Estimate a correlation coefficient for the following: SUBJECT X Y 1 1 8 2 2 7 3 5 5 4 2 4 5 6 5 6 1 3 7 5 4 8 5 8 9

### The Correlation Between the Returns

The correlation between the returns on Ceramics Craftsman, Inc., and the returns on the S&P 500 is 0.675. The variance of the returns on Ceramics Craftsman, Inc., is 0.004225, and the variance of the returns on the S&P 500 is 0.001467. What is the beta of Ceramics Craftsman stock?

### Correlation and Prediction

1. What statistic do you use to precisely describe a correlation? 2. Why is the regression line "the line of best fit"? 3. What are the properties of Z scores and the Z distribution? 4. Why do you study samples and not populations?

### More appropriate variable to replace one of the two variables.

We must use common sense when we analyze data and discover correlation exists. A large value for a correlation coefficient does not necessarily mean that real correlation exists. One of the classic examples is the study that discovered a high correlation between the increased use of illegal drugs by high school students and th

### Random Sample and correlation

A sample of 20 countries has been randomly selected. Attached is a chart indicating the literacy rate, population, and GDP for each country. Compute the correlation among the variables. In other words, find the correlation between: literacy and population, literacy and GDP, and population and GDP. At the .05 significance lev

### Practical Application of Correlational Research in the Workplace

Share the practical applications of the study from the Unit 2 Individual Project. How would the results of this survey be used in the workplace? Briefly describe co relational research. Name a variable from this study and one from the workplace that might prove to provide a co relational relationship and explain why you would

### Random Variable Problem

The total population of car passengers involved in traffic accidents are classified into six categories: two factors (one with 2 levels and one with 3 levels) crossed. The first factor is: Survivors (X1=0), Fatalities (X1=1). The second factor is: No Belt (X2=0), Adult Belt (X2=1), and Child Seat (X2=2). The proportions are as f

### Positive Linear Correlation

See the attached file for full problem description. In Display the data in a scatter plot. Then find the sample correlation coefficient r. Determine whether there is a positive linear correlation, a negative linear correlation, or no linear correlation between the variables. What can you conclude? The annual per capita sug

### Correlations, Correlation Coefficient, and Random Variables

Please help with the following problems. 1. Describe the correlation in this graph (see graph in attachment) 2. Which of these is true for the correlation coefficient? - its range is [-1 1] - we use r to represent it - we use r^2 to represent it - both 1 and 2 - both 1 and 3 3. Indicate whether the random variabl

### coefficient of determinations and correlation coefficient

A sample of eight observations of variables x and y is shown below: x 5 3 7 9 2 4 6 8 y 20 23 15 11 27 21 17 14 Also, Correlation of x and y = -0.991 i) Calculate and interpret the coefficient of determinations (Rxy2 and Ryx2 ) ii) How is the value of the correlation coefficient ryx affected

### Statistics: Construct and analyze Scatter Diagrams

11. Make up a scatter diagram with 10 dots for each of the following situations: (a) perfect positive linear correlation, (b) large but not perfect positive linear correlation, (c) small positive linear correlation, (d) large but not perfect negative linear correlation, (e) no correlation, (f) clear curvilinear corr

### What is correlation?

1.What is correlation? What are the different types of correlation? Why is it important to determine correlation? 2. How is the strength of a correlation determined?

### WidgeCorp: Simple and Multiple Correlation and Regression

You're in a brainstorming session at WidgeCorp, where no idea is too outrageous. You're discussing penetration in the school lunch market. Ideas around school lunch subsidies, Internet subsidies, and Internet target marketing are being discussed. As the end of the meeting, the group asks you to prove or disprove some assumptions

### Correlation Between Income and Education

There is a correlation between income and education. We find that people with higher income have more years of education. GIVE A STATISTICAL EXAMPLE OR EQUATION OF THIS: When we know there is a correlation between two variables, we can make a prediction. If we know a group's income, we can predict their years of education.

### Correlation Coefficient - least square regression

A movie studio wishes to determine the relationship between the revenue from rental of DVDs and videotapes of comedies and the revenue generated from the theatrical release of such movies. The studio has the following bivariate data from a sample of fifteen comedies released over the past five years. These data give the revenue

### Analysis of Lowell data in SPSS

? Open the S Using the hypothesis testing procedure in the course text, select any two appropriate variables from the Howell data set. ? Retrieve the descriptive statistics for each of the nine project variables in spss121017.doc. Select the variables that you will use to perform your SPSS analysis this week. Using the varia

### Distinction between the Pearson and Spearman correlations

1. What information is provided by the sign (= or -) of the Pearson correlation? 2. What information is provided by numerical value of the Pearson correlation? 20. What is the major distinction between the Pearson and Spearman correlations? 10a. A professor obtains SAT scores and freshman grade point averages (GPAs) for a

### Correlation

? Explain how correlation is often miscast as causation. Specifically, as it relates to how cause is attributed to a variable when in fact, there is no causal relationship but only a correlation between the two variables. ? Give an example of correlations. ? Using the example, describe how correlation might be interpreted i

### Value of R

10. a. Use one of the raw score formulas to find r for the following data. What is the value of r? _____ (2 Points) Case X Y 1 13 5 2 17 45 3 9 0 4 11 18 5 15 25 X-bar =13 SDx = 3.16 Y-bar =18 Sdy = 17.81 b. What does r tell us? ___________ (2 Points) Describe the strength of r. ________ (2 Points)

### Mean, range and constructing 2 bivariate tables percentage

Using the mean and range, (to describe the distribution of responses) to the question, how often have you used the library as a place to study" for ALL respondents Then I need help to construct 2 bivariate tables. Each of the title has to be titled, percentage, and include the number of cases on which the percentages are bas

### Correlation coefficient and coefficient of determination.

Using the countries in South America, let's analyze the relationship between GNP and infant mortality rate (IMR). (See attached) a. Construct a scatterplot from the following data, predicting IMR from GNP. What is the relationship between GNP and IMR for these 10 countries in South America? b. Does it appear (visually) t