Results 1 to 5 of 5

Math Help - Linear Regression Model

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    3

    Linear Regression Model

    Hi, I don't really understand how I go about this problem. I understand regression but I need a little help here.

    Question:
    Reaction time to a stimulus (y seconds) is believed to be related to the amount of the drug in the bloodstream (x%) by a simple linear regression model where

    E(y) = -0.1 + 0.8x
    and with \sigma = 0.2

    What proportion of individuals with 4% of the drug in the bloodstream will have a reaction time in excess of 3 seconds?

    Well, so far I have substituted in (x = 4) into the equation to get
    E(y) = 3.1

    I'm not sure how to calculate the proportion. Could somebody help me?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Ond
    Ond is offline
    Junior Member
    Joined
    Feb 2009
    Posts
    28
    Well, one way could be that you have the Y that's normally distributed with mean 3,1 and 0,2 in standard deviation, and you're supposed to find the probability of Y>3?

    Am I understaning that correctly? If so, that's a pretty simple problem to solve.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Mar 2009
    Posts
    3
    Yes that is what I was thinking.
    I am wondering now if i get the Probability of Y > 3, is this the same as the proportion >3?

    Are Probability and Proportion related?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Mar 2009
    Posts
    3
    Quote Originally Posted by Ond View Post
    Well, one way could be that you have the Y that's normally distributed with mean 3,1 and 0,2 in standard deviation, and you're supposed to find the probability of Y>3?

    Am I understaning that correctly? If so, that's a pretty simple problem to solve.
    What type of distribution would this be z, t ?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Ond
    Ond is offline
    Junior Member
    Joined
    Feb 2009
    Posts
    28
    Hi there again.

    I think this would be Z since the standard deviation is known, the t-distribution is used when it's unknown.

    Regards.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Multivariate Linear Regression Model Question
    Posted in the Advanced Algebra Forum
    Replies: 0
    Last Post: September 8th 2011, 04:37 AM
  2. Replies: 2
    Last Post: October 6th 2010, 06:13 PM
  3. Linear Regression Model Matrix
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: October 11th 2009, 07:27 PM
  4. Simple linear regression model
    Posted in the Business Math Forum
    Replies: 0
    Last Post: April 6th 2009, 07:58 AM
  5. Replies: 0
    Last Post: October 25th 2008, 09:36 PM

Search Tags


/mathhelpforum @mathhelpforum