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Correlation Explained Reading Grades

4.How much of the math grade can be explained by the PE grade? How much of the writing grade can be explained by the reading grade?Problem:How much of the math grade can be explained by the PE grade? How much of the writing grade can be explained by the reading grade? Correlation Coefficient (R) between: A ...there is mo

The Correlation Coefficient at a Particular Significance Level

1. A math teacher believes there is a correlation between a student's Exam I score (x) and the Final Exam score (y). Below is the test data (although Jean's scores were blotted out by accident) and the summations from all the students' scores in the class. Determine the appropriate correlation coefficient, r, and whether there i

Statistics - Correlation Coefficients - Interval variables

Determine correlation between pairs of all interval variables (i.e., absences with P.E) PE with math, math with writing, etc). Standard Test Scores Name Gender Absences PE Math Writing Reading Alex Boy 5 49 85 86 80 Anthony Boy 18 51 39 71 75 Douglas Boy 1 82 74 78 79 Jorge Boy 4 56 66 68 60 Joshua Boy 5 83 79 78 7

Linear relationship and the sample correlation coefficient

In which data set is there evidence of a strong nonlinear relationship between the two variables? (x,y u,v w,t m,n no data sets at all) Which data set indicates the strongest positive linear relationship between its two variables? (x,y u,v w,t m,n) Which data set has an apparent negative, but not perfect linear rela

Correlation Between Fat and Cancer

Researchers have shown that there is a positive correlation between average fat intake and the breast cancer rate across countries. Does this correlation mean that dietary fat is a contributing cause of breast cancer? Explain

Covariance and Correlation Calculations

Covariance and Correlation. Show all work in computing the covariance and coefficient of correlation for the data set: (-1,10), ( 3,9), (5,7), (9,2). (nearest 0.01) sxy = _______________ r = ________________ Simple Linear Regression. 1. Consider t

Business Examples: Positive, Negative and Spurious Relations

Give three real life or business examples of each of the following: a) Positively related events. Explain why they are directly related. b) Negatively related events. Explain why they are inversely related. c) Spuriously related events. Explain why they are spuriously related

The Correlation Coefficient Between Two Variables

A -0.947 correlation coefficient has been found between two variables after examining 43 pairs of observations. What can be concluded? a.There is a strong positive relationship between the two variables. b.There is a strong negative relationship between the two variables. c.There is a weak positive relationship between the

Analyzing Bivariate Relationships

1. For the following data on 10 persons, construct a scatterplot showing the relationship between age and number of children, and describe the relationship in verbal terms. Person (i) Age (X1) Number of Children (Yi) 1 42 5 2 26 2 3 38 2 4 23 1 5 21 0 6 19 0 7 79 6 8 25 2 9 75 4 10 67 3 2. Suppose social psycho

Linear equations for price and processor speed

The following data show the retail price for 12 randomly selected laptop computers along with their corresponding processor speeds in gigahertz. Computer Speed Price 1 2.0 $ 2,689 2 1.6 1,22

Statistics - Correlation and Causation - Example

Does correlation equal causation? Does the strength of correlation depend on the direction? What is the meaning of a zero correlation? Explain your answers. Provide an example of variables you feel might be correlated in your place of business. For instance, hours of studying would be correlated to scores received on a test.

Linear Regression and Correlation for Homes in Minnesota

A sample of 12 homes sold last week in St. Paul, Minnesota, selected. Can we conclude that, as the size of the home (reported below in thousands of square feet) increase, the selling price (reported in thousands) also increases? Home size Selling price 1.4 100 1.3 110 1.2 105 1.1 120 1.4 80 1.0 105 1.3 110 0.8 85 1.2

Correlation analysis

Given the data below, 8 100 5 85 6 89 4 60 3 50 1 20 From a data analysis regarding the Correlation feature the following results were obtained. Column 1 Column 2 Column 1 1 Column 2 0.969486 1 Describe what the results mean for this data set?

T test for Correlation coefficient

A correlation coefficient for Bee Taylor's Department Store in Mayberry, NC, between sales ability and amount of sales is Sales ability is measured on an interval scale and amount of sales is measured on a ratio scale. Note that the correlation was conducted on 42 sales employees. Test this coefficient by using a t test and

Multiple choice question from Correlation Coefficient

A study was conducted to determine if there was a relationship between A study was conducted to determine if there was a relationship between the prices a non-member of a club paid for various publications and the prices that a member paid for the same publications. The data collected is shown below. Non-member Membe

Correlation Coefficient and Determination- Schering-Plough Corporation

Listed below are the net sales for Schering-Plough Corporation (a pharmaceutical company) and its subsidiaries for the six years from 1997 to 2002. The net sales are in millions of dollars. Year Net Sales 1997 $ 6,714 1998 7,991 1999 9,075 2000 9,775 2001 9,762 2002 10,180 a. Determine

Coefficient of Correlation and Effects

1. The following sample observations were randomly selected. Determine the coefficient of correlation. Interpret. X: 4 5 3 6 10 Y: 4 6 5 7 7 2. Can you please share with me some examples of strong and weak correlation coefficients? What are the variables?

Independent and Dependent Relationship in Correlation

1) Is an understanding of the dependent/independent relationship important before attempting to discern correlation? 2) Do you suppose there are many relationships in nature where there is a near perfect dependency such that correlation is near 1 or -1?

Least-Squares Regression Lines for Bivariate Data

Bivariate data for the quantitive variables x and y are given in the table below. These data are plotted in the scatter plot shown next to the table. In the scatter plot, sketch an approximation of the least-squares regression line for the data. X Y 4.2 6.7 4.6 6.2 4.5 5.5 8.6 3.4 3.6

Correlation Analysis: Significance of Correlations

Using the same sample data listed in the Background Response below, calculate the variance of the same sample data, and use that as the population variance. Use the P-Value Method for the calculations. Background: 1. Ask fifteen (15) people to estimate the distance (in miles) from Washington D.C. to New York, New York (sa

Correlation and Regression (Descriptive Statistics)

Finding the Equation of the Regression Line and Making Predictions. In each case, find the regression equation, letting the first variables be the independent (x) variable. Find the indicated predicted values. 1. Tobacco and Alcohol in Children's Movies: Refer to data Set name Children movies and use the times that the

Scatter Diagram Characteristics

A graph that shows the pattern of the relation of two variables is a scatter diagram. How would you define or describe a scatter diagram? When making a scatter diagram, the lowest value on the horizontal axis us usually what value? The overall shape of a scatter diagram should be roughly square. What is the difference between

Methods of Computation and Correlation Lines

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 correlation. Not

Differentiate between correlation and causation

Share the practical applications of studying job satisfaction level of employees. How would the results of this survey be used in the workplace? Briefly describe correlational research. Name a variable from this study and one from the workplace that might prove to provide a correlational relationship and explain why you would

Hypothesis Testing, coefficient of correlation, coefficient of determination.

Please see the attached file for fully formatted questions. ------------------------------------------------------------------- Please use the 5 step hypothesis method for each problem. 1. The management of Discount Furniture, a chain of discount furniture stores in the Northeast, designed an incentive plan for salespe

Testing for serial correlation

Membership on a stock exchange for five years is given below: year members 1996 520 1997 510 1998 505 1999 508 2000 512 Use the exponential smoothing procedure to obtain estimates of the trend (this is not the logarithm approach here. Set the smoothed value for 19

Descreptive Statistics - Correlation

A researcher demonstrated a correlation of .60 between teacher attire and student academic performance across 150 grade schools in her state. She concluded that encouraging teachers to be properly attired will increase academic performance. Based on your professional roles, briefly describe three correlational studies you


1. Which is the weakest correlation? a. +0.76 b. +0.21 c. -0.01 d. -0.88 2. What would a correlation of .35 would be called? a. Moderate b. Weak c. Very Strong d. Very Weak 3. Which correlation coefficient indicates the strongest relationship? a. 0.00 b. +0.50

Spearman Rank correlation in SPSS

A common concern for students and teachers is the assignment of grades for essays or term papers. Because there are no absolute right or wrong answers, these grades must be based on a judgment of quality. To demonstrate that these judgments actually are reliable, an English instructor asked a colleague to rank-order a set of t

Point Biserial Correlation

To test the effectiveness of a new studying strategy, a teacher randomly divides a sample of 8 students into tow groups, with n = 4 in each group. The students in group one receive training in the new studying strategy. Then all students are given 30 minutes to study a chapter before taking a quiz. The quiz scores for the t