Page 262 - Industrial Process Plant Construction Estimating and Man Hour Analysis

Statistical applications to construction Chapter 12 241

2
The coefficient of determination, R , is exactly +1 and indicates a positive fit
(Fig. 12.3.1).
All data points lie exactly on the straight line. The relationship between X and Y
variables is such that as X increases, Y also increases.

Example 12.3.2
Plot a graph for hydrotest (Table 12.3.2)
Work scope: Hydrostatic testing
Facility—Industrial plant
Data for input:
X: 2, 2.5, 3, 4, 6, 8, 10, 12, 14, 16, 18, 20, and 24
y: 0.022, 0.021, 0.025, 0.034, 0.050, 0.067, 0.084, 0.101, 0.118, 0.134, 0.151,
0.168, and 0.202

TABLE 12.3.2 Hydrotest pipe
x y
Pipe Man-hours per lineal foot
Size 0.375 or less
00
2 0.022
2.5 0.021
3 0.025
4 0.034
6 0.050
8 0.067
10 0.084
12 0.101
14 0.118
16 0.134
18 0.151
20 0.168
24 0.202