Dear R-helpers, I'm for sure not familiar with R, but it seem like a nice sofware tool, so I've decided to try using it. Here is my problem I just can't figure out: I'd like to do least square fit of a straight horizontal (a = 0) line y = ax + b through some data points x = (3,4,5,6,7,8) y = (0.62, 0.99, 0.83, 0.69, 0.76, 0.82) How would i find b????? All the best, Ked [[alternative HTML version deleted]]
If you really want to fit a horizontal line then the best estimate (meaning least squares) for b is mean(y), regardless of the actual x values, which becomes clear if you look at your design matrix / regressor matrix . In general least squares regression could be done with lsfit(). In your case the design matrix (X matrix) is a simple vector of ones. K?re Edvardsen schrieb:> Dear R-helpers, > > I'm for sure not familiar with R, but it seem like a nice sofware tool, > so I've decided to try using it. > > Here is my problem I just can't figure out: > > I'd like to do least square fit of a straight horizontal (a = 0) line y > = ax + b through some data points > > x = (3,4,5,6,7,8) > > y = (0.62, 0.99, 0.83, 0.69, 0.76, 0.82) > > How would i find b????? > > All the best, > Ked > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >
b = mean(y) On 08/12/06, K?re Edvardsen <ked at nilu.no> wrote:> Dear R-helpers, > > I'm for sure not familiar with R, but it seem like a nice sofware tool, > so I've decided to try using it. > > Here is my problem I just can't figure out: > > I'd like to do least square fit of a straight horizontal (a = 0) line y > = ax + b through some data points > > x = (3,4,5,6,7,8) > > y = (0.62, 0.99, 0.83, 0.69, 0.76, 0.82) > > How would i find b????? > > All the best, > Ked > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- ================================David Barron Said Business School University of Oxford Park End Street Oxford OX1 1HP