Warning!

1 / 23

# Warning! - PowerPoint PPT Presentation

Warning! Excel 97 (and almost all other statistical software and textbooks) define Residuals the same way as in this course: Residual = Observed value – Fitted Value But Excel 2000 uses Residual = Fitted Value – Observed Value Result: Residual Plots from Excel 2000 are upside down!.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Warning!

Excel 97 (and almost all other statistical software and textbooks) define Residuals the same way as in this course:

Residual = Observed value – Fitted Value

But Excel 2000 uses

Residual = Fitted Value – Observed Value

Result:

Residual Plots from Excel 2000 are upside down!

Logarithms and Exponential Relationships

Basic Rules:

ln(a x b) = ln (a) + ln(b)

ln(ex) = x,

Equivalently,

e(ln y) = y

Some Special Cases:

• ln(y) = ln(a) + bx equivalent to y = aebx
• Examples:
• ln(y) = 3 + 2 x => y = ??
• y = 5e-1.7x => ln(y) = ??

Some Special Cases:

• ln(y) = ln(a) + bx equivalent to y = aebx
• Examples:
• ln(y) = 3 + 2 x => y = ??
• y = 20.08e2x
• y = 5e-1.7x => ln(y) = ??
• ln(y) = 1.609 – 1.7 x

Example 2: Power Law

y = axb equivalent to ln(y) = ln(a) + b ln(x)

Examples:

y = 7x3 => ln(y) = ??

ln(y) = -0.2 + 1.5 ln(x) => y = ??

Example 2: Power Law

y = axb equivalent to ln(y) = ln(a) + b ln(x)

Examples:

y = 7x3 => ln(y) = ??

ln(y) = 1.946 + 3 ln(x)

ln(y) = -0.2 + 1.5 ln(x) => y = ??

y = 0.819 x1.5