After some consideration I have decided that the corruption model is seriously flawed. First of all, in ancient civilisations, the corruption level may be a bit too high, although I concede that the distance from the central authority is probably the best mechanism for controlling the levels.
However, in the modern age, the corruption model is completely broken. I do not think that distance from the capitol has any relevance to corruption today. Indeed, the capitol is arguably the highest corruption place in any country. Also, in Civ III, corruption is completely crippling. That is not something we see today. Corruption levels are tied to technology and education as well as government type. In line with that, country size is not nearly as great a factor. A developing world economy, international credit facilities, etc has changed the very concept of trade & commerce.
To that end, I believe that a strong case can be made to have educational facilities and commercial facilities reduce corruption with increasing effectiveness as the technical level of the civilisation advances. If this can not be accomplished by a tech level index, then perhaps simply make the institutions themselves individually more effective; i.e. such as universities more effective than libraries and research centers vastly more effective than universities.
However, in the modern age, the corruption model is completely broken. I do not think that distance from the capitol has any relevance to corruption today. Indeed, the capitol is arguably the highest corruption place in any country. Also, in Civ III, corruption is completely crippling. That is not something we see today. Corruption levels are tied to technology and education as well as government type. In line with that, country size is not nearly as great a factor. A developing world economy, international credit facilities, etc has changed the very concept of trade & commerce.
To that end, I believe that a strong case can be made to have educational facilities and commercial facilities reduce corruption with increasing effectiveness as the technical level of the civilisation advances. If this can not be accomplished by a tech level index, then perhaps simply make the institutions themselves individually more effective; i.e. such as universities more effective than libraries and research centers vastly more effective than universities.