Computational Methods in Civil Engineering
I’m looking for someone to write me a matlab code for this project please let me know if you can. The project is this:
The attached text file contains about 1,000 test results (from Prof. I-Cheng Yeh, Chung-Hua Univer- sity, Taiwan) on the strength of concrete with different mixture compositions and curing times.
The goal of regression here is to predict the concrete strength (x9) as a function of the other variables, so that concrete of the required strength can be made with less trial and error. The variables are:
x1 = cement content (kg per m3)
x2 = slag content (kg per m3)
x3 = fly ash content (kg per m3)
x4 = water content (kg per m3)
x5 = superplasticizer content (kg per m3) x6 = coarse aggregate content (kg per m3) x7 = fine aggregate content (kg per m3) x8 = curing time (days)
x9 = concrete compressive strength (MPa).
Fit each of the following function classes using least squares:
x9 as a (a) linear, (b) quadratic, or (c) cubic polynomial function of x1;
(d) x9 as a linear combination of x1, x2, x3, …x8, i.e. x9 1×1 + 2×2 + 3×3 +…+8×8
(e) x9 1(1 exp(x8/2))
(f)x9 1×1+2×2+…+6×6+7×7+8(1exp(x8/9))
(e-f require nonlinear least squares fitting)
Make a table of RSS, R2, number of parameters, and AIC for cases a-f. Based on your results, what do you conclude about the best regression function for concrete compressive strength?
