While I thought that Mead Jennings' article on codesharing (Airline Business, June 1995) was a reasonable portrayal of GRA's study, there are a few statements that I take issue with.

Where you note that we qualified our results and therefore discounted our findings before they were presented, it is fairly standard practice to note the limitations of one's research when results are reported. It is somewhat disconcerting to be criticised, even indirectly, for trying fairly to portray the results of a complex research project.

We find the contrast of the GRA report with the General Accounting Office report even more disconcerting. GRA met with a number of carriers and reviewed data that they were willing to provide. However, these data were always in aggregated form, and therefore it was not possible to use them to assess the effects of codesharing on carrier market shares while controlling for other factors that could be affecting these market shares contemporaneously.

While we did report what the carriers told us in Chapter 3 of our report, we did not rely on them in estimating the impact of codesharing on carrier market shares and revenues. As such, we believe the GRA results present a better picture of the impact of codesharing. The GAO estimates are probably a good evaluation of the overall benefits of the airline alliances, which extend well beyond codesharing.

Finally, GRA did note British Airways' investment in USAir on pages 36-38 of our report, contrary to what is stated in your article.

Richard Golaszewski

Executive vice-president

GRA Inc

Jenkintown, PA, USA

Editor's response: We did not intend to criticise GRA for noting the limitations of its research, but simply to draw to readers' attention the fact that these limitations existed.

The GRA and GAO reports are bound to be compared because they cover the same subject. Our article pointed out clearly that GRA used an academic model to evaluate the impact of codesharing, whilst the GAO used airline reports. Both approaches suffer limitations, as we pointed out. GRA's conclusion that the BA-USAir alliance provided little benefit to the US airline industry was based purely on the alliance itself. GAO specifically noted that BA's $400 million investment in USAir was an equalising force.

Source: Airline Business