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Dear professor Bliemer,

I am using the model averaging approach, following the example from the Ngene manual (page 132). If I have two models (M1 and M2), and I multiply the efficiency measure for model ‘M1’ by 1.5 in the Ngene syntax, would that mean that the weight I'm giving to M1 is 0.6 and the weight of M2 would be 0.4? I read your paper with Rose and Scarpa (2009) on the model averaging approach (great paper and very easy to follow!), and in there, you present the case study with the 5 models, using three different weights (table 2), but I'm not sure about the Ngene syntax equivalent. For the example in the Ngene manual (page 133), would this be correct?

M1 --> In the Ngene syntax (eff): 1 ; weight: 0.15
M2 --> In the Ngene syntax (eff): 2 ; weight: 0.31
M3 --> In the Ngene syntax (eff): 1.5 ; weight: 0.23
M4 --> In the Ngene syntax (eff): 1 ; weight: 0.15
M5 --> In the Ngene syntax (eff): 1 ; weight: 0.15

Many thanks!

Best wishes,

Pamela.

Sorry for the delayed response, I was on holidays for a week

The weight is not exactly the weight of a MODEL, but rather a weight of the EFFICIENCY CRITERION for that model.

For example:

;eff = 2* m1(mnl,d) + 1* m2(mnl,a)

Then the combined efficiency criterion that is minimised is 2 times the D-error of the design for model m1 and 1 time the A-error of the design for model m2.

Michiel