Statistical Analysis of the Tensile Strength of Coal Fly Ash Concrete with Fibers Using Central Composite Design

Table 5

Observed, predicted, and residual values of the two responses and .

	Observed	Predicted	Residual	Observed	Predicted	Residual
1	4.12	4.390851	−0.270851	3.42	4.238635	−0.818635
2	2.54	2.850557	−0.310557	2.05	2.616282	−0.566282
3	3.92	3.909381	0.010619	3.02	3.245694	−0.225694
4	2.71	2.739087	−0.029087	2.09	2.063341	0.026659
5	3.36	3.414341	−0.054341	2.48	2.523305	−0.043305
6	4.18	3.859047	0.320953	4.43	3.682717	0.747283
7	2.34	2.180224	0.159776	1.77	1.586246	0.183754
8	4.32	4.213165	0.106835	4.21	3.689776	0.520224
9	3.91	3.918669	−0.008669	4.41	4.404801	0.005199
10	3.98	3.918669	0.061331	4.52	4.404801	0.115199
11	3.89	3.918669	−0.028669	4.39	4.404801	−0.014801
12	3.95	3.918669	0.031331	4.45	4.404801	0.045199
13	3.93	3.918669	0.011331	4.43	4.404801	0.025199