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4.4  Further Numerical Examples

The application of the distance functions presented in the previous subsection to the hypothetical sample used earlier gives the results shown in Table 4, where the simple (unrestricted) chi-squared results are added for comparison. In cases where limits are imposed on the degree of adjustment of the weights, it cannot be expected that a solution will always be available. For this reason, care is needed in the choice of and , as discussed below.

The values of and were initially selected as being well outside the range of ratios obtained using the other distance functions. When the range was reduced to the potentially restrictive values of and , none of the ratios obtained was actually at the limits specified. Nevertheless, the change to the weighting function produces a different set of weights, as shown by comparisons in Table 4: some actually move further away from their initial, or survey, weights.

Table 4– Revised weights using alternative distance functions
A B Chi-squared
1 3.000 2.674 2.654 2.706 2.513 2.483 2.753
2 3.000 2.228 2.260 2.178 2.408 2.400 2.109
3 5.000 5.998 6.012 5.976 6.162 6.187 5.945
4 4.000 3.944 3.926 3.974 3.951 4.019 4.005
5 2.000 2.514 2.521 2.501 2.534 2.493 2.484
6 5.000 4.456 4.423 4.510 4.189 4.138 4.589
7 5.000 5.729 5.717 5.747 5.911 6.094 5.752
8 4.000 3.944 3.926 3.974 3.951 4.019 4.005
9 3.000 2.228 2.260 2.178 2.408 2.400 2.109
10 3.000 3.086 3.074 3.106 3.213 3.325 3.120
11 5.000 5.998 6.012 5.976 6.162 6.187 5.945
12 4.000 3.814 3.762 3.897 3.645 3.769 3.985
13 4.000 5.108 5.136 5.065 5.094 4.990 5.019
14 3.000 3.490 3.487 3.494 3.604 3.680 3.490
15 5.000 4.665 4.666 4.665 4.442 4.314 4.678
16 3.000 2.370 2.380 2.355 2.428 2.408 2.345
17 4.000 5.191 5.232 5.128 5.115 4.993 5.070
18 5.000 4.603 4.604 4.600 4.366 4.237 4.614
19 4.000 5.028 5.043 5.001 5.069 4.986 4.967
20 3.000 2.228 2.260 2.178 2.408 2.400 2.109

The choice of and shown in the penultimate column of the table, actually places some adjustments to the weights at the lower limit of the range: for individuals 2, 9 and 20, the value of is equal to . However, no adjustments are at the upper range specified. If is raised to (with unchanged), unreported results show that individual 16 is placed at the lower limit, along with 2, 9 and 20 as before; in addition individuals 5, 13, 17, 19 are pushed to the upper limit of . The attempt to raise to means that no solution is possible. However, if is set to the higher value of then is found to be the highest value (where the range of variation is limited to the second decimal point) of for which a solution is possible. The two highest ratios needed in this case are for persons 13 and 17, who have values of and respectively. If is kept at this value of the lowest value of for which a solution exists is . In this case individuals 1, 2, 6, 9, 16 and 20 are placed at the lower limit and individuals 5, 13, 17 and 19 are placed at the upper limit. Clearly, some care needs to be exercised in the choice of upper and lower limits.

While these examples help to explore the characteristics of the different approaches, it is necessary to examine the practical implementation of the method. This is carried out in the following section.

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