To randomize the order of the eight runs
select any column in the table of random numbers such as column 20.
read the numbers in column 20 starting from the top (i.e. 1, 3, 5, 0, 6, 1, 4, 2, 1, 8, etc). Ignore the numbers that are less than 1 or greater than 8 such as 0 and 9. Also ignore any number when it appears a second time or more, as I does here.
continue reading until 8 different numbers that are greater than 0 but less than 9 are selected (i.e. 1, 3, 5, 6, 4, 2, 8, 7).
runs 1, 3, 5, 6, 4, 2, 8, and 7 are performed in that order as shown in Table 9.
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Note : '-' and '+' represents the low and high level of the factors.
The 32 combinations were carried out in a random manner. A single rubber glove was used. The length of the middle finger (in pixel) was measured for each of the combination. the actual length was 50 pixel.
Analysis of the experimental data showed that the factors that significantly affected the average measurement of finger length were A (aperture size), C (binarization threshold), and D (corner angle threshold). The interactions between A and C, between A and D, and between C and D were found to also significantly affect the average length of the middle finger. All of the factors affected the variability in the measurement of finger length. The practical interpretation of these findings are given below.
The high level of A produced average measurements that were close to the actual length (i.e. 50 pixel) for both the low and high levels of C and D. The high level of C produced average measurements that were close to the actual length for both the low and high levels of D. The high levels of A, B, C, D, and G produced less variability in the measurements. Therefore, it was recommended that all of the factors be set at the high level except for E and F. Confirmation runs confirmed that the measurements are close to the actual value when the factors are set at these levels.
The above findings and interpretations are valid over the factor levels that were investigated.
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