statistics

posted by .

Please Help! My book and instructor are no help. Please help me understand why I need to make a scatter diagram, when dealing with bivariate data, and how to find SS(x), SS(y), SS(xy), and r. I have all the formulas, but don't understand. Thanks!


I don't know that the diagram is required to be drawn, if you have all the xi, yi.

See http://www.ms.unimelb.edu.au/~s620202/EMS05ch7.pdf

Using Excel, there is a method of doing the scatter plot, then a fitted line, and from that, determining SS.

So, I really guess I cant offer much help....is there another student in your class you can team up with...that is my recommendation.


Why a scatter diagram?
Well, to repeat a phrase, a picture is worth a 1000 words. With a scatter diagram, one can usually see, at an instant, any correlation between the variables x and y.

SS(x), SS(y), and SS(xy) are, by themselves, not very interesting or informative. However, they are components of calculations that are very helpful. So, dividing SS(x) by n-1 gives the sample variance of the x value; a very helpful statistic.
Combining the three statistics, according to your formula, gives r, which is a correlation statistic. r provides a measure of the linear relationship (correlation) between x and y. With a high degree of correlation, one can use values of x to predict values of y -- Which is what regression analyses is all about.

I hope this helps.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. statistics

    3. The following data shows expenditures (in millions of dollars) and case (sales in millions) for seven major soft drink brands. Show a scatter diagram of the data and describe in words what it tells you. Calculate the correlation …
  2. environmental science

    Please check this: Scientists use statistics to a. graph data b. analyze data c. communicate ideas to each other d. all of the above B ( in my book it says: scientists rely on and use statistics to summarize, characterize, analyze, …
  3. language

    okay i read the book Royally Jacked for english and i had to return the book and i need to finsh my book report ASAP ! i need to know 20 vocab words used in the book , venn diagram , plot diagram , summary 3-10 ! and i cant FAIL . …
  4. statistics

    These data were generated using the equation y = 2x + 1. A scatter diagram of the data results in five points that fall perfectly on a straight line. x 0 1 2 3 4 y 1 3 5 7 9 (a) Find the correlation coefficient.
  5. math

    Consider the following bivariate data. Point A B C D E F G H I J x 3 4 2 1 7 2 1 0 4 2 y 1 7 3 3 6 6 5 0 6 2 (a) Construct a scatter diagram of the given bivariate data. (Do this on paper. Your instructor may ask you to turn in this …
  6. math help

    Can some one help me with this one??? Consider the following bivariate data. Point A B C D E F G H I J x 3 4 2 1 7 2 1 0 4 2 y 1 7 3 3 6 6 5 0 6 2 (a) Construct a scatter diagram of the given bivariate data. (Do this on paper. Your
  7. math

    Consider the following bivariate data. Point A B C D E F G H I J x 3 4 2 1 7 2 1 0 4 2 y 1 7 3 3 6 6 5 0 6 2 (a) Construct a scatter diagram of the given bivariate data. (Do this on paper. Your instructor may ask you to turn in this …
  8. Statistics

    I have all the data, I just need someone to tell me how to start xc Please! I've been working on this for 5 hours now! 8. Calculate the equation of the least squares regression line. Draw this line on your scatter plot. The point (x,y) …
  9. Pre-Calc

    For the data set shown by the table, a. Create a scatter plot for the data. (You do not need to submit the scatter plot) b. Use the scatter plot to determine whether an exponential function or a logarithmic function is the best choice …
  10. Statistics/Math

    I have population data for the last 50 years (total population for a country), that I need to make linear. In its original it has a positive relationship (looking at a scatter plot) but it is not linear. There are three smaller periods …

More Similar Questions