Lecture 4 notes - 2.5 SUMMARY AND DISPLAY OF...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
2.5 SUMMARY AND DISPLAY OF MULTIDIMENSIONAL DATA 2.5.1 2-Dimensional Data ( X 1 , Y 1 ) , ( X 2 , Y 2 ) , ... ( X n , Y n ) eg X = height Y = weight X = SAT verbal Y = SAT math Scatter plot. Plot Y versus X . Example: Devore 7e Ed. p.448 (MINITAB: Graph Scatterplot... Simple) For multiple samples, (e.g. height vs. weight in men and in women) use one scatter plot, but use different symbols or colors for each sample to mark the points on the graph. MINITAB: Graph Scatterplot... With groups A numerical measure for strength of association between the two variables is the sample correlation coefficient r : (Example: Devore 7e. p.485–488.) r = n i =1 ( X i - ¯ X )( Y i - ¯ Y ) ( X i - ¯ X ) 2 ( Y i - ¯ Y ) 2 = 1 n - 1 n i =1 X i - ¯ X S x · ‡ Y i - ¯ Y S y · where S 2 x = ( X i - ¯ X ) 2 / ( n - 1) , S 2 y = ( Y i - ¯ Y ) 2 / ( n - 1) Note if X i = Y i all i then r = +1 X i = - Y i all i then r = - 1 Can show - 1 r 1 . (MINITAB will compute r . Use Stat Basic Statistics Correlation... ) 1
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2.5.2 Least Squares ( X 1 , Y 1 ) , . . . . . . , ( X n , Y n ) Suppose Y = response variable X = explanatory variable
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern