Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Least-squares problem

  1. Aug 6, 2005 #1
    Hello,

    I'm stuck with a chemistry problem as I did not have any statistics course so far and don't really understand the explanations I found online.

    It's about dating rock and I'm supposed to use the least-squares method to calculate the slope and intercept of a linear isochron.

    I can solve the problem with any given pair of data, but my results differ quiet a lot when I try to use a least-squares method as described on different websites (so I probably don't understand it, which also shows as I don't quiet know what the result actually represents)

    Here's a rather random set of data

    x - y
    700 - 17
    40 - 2
    100 - 3
    150 - 4

    further given:
    slope m=e^(labda t) - 1
    and
    t=(1/labda)ln(m+1)
    labda = 1.4x10^-11

    Any help is greatly appreciated

    lil'me

    edit: I know that I get the slope as one result and can calculate the time with it. I also know how to calculate the intercept if y=mx+b and mx being the slope and b the intercept. I just don't know which figure to use for y.
     
    Last edited: Aug 6, 2005
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted