Experiment with other pop reduction values

[jipclaassens]

bv 1% ipv 2.5%

Indicators:

• area per DoU (@cjacobscrisioni doet eerst #78 hiervoor)
• pop dens per DoU

[jipclaassens]

Europe, difference proportional and absolute reduction:

Density: 1%

2.5%

Land area: 1%

2.5%

[cjacobscrisioni]

@jipclaassens , these look as expected. But Europe is fairly well-behaved as is. Can you possibly also make these for e.g. Africa?

[jipclaassens]

@jipclaassens , these look as expected. But Europe is fairly well-behaved as is. Can you possibly also make these for e.g. Africa?

running 1%, 2.5% and 5% as we speak.

[jipclaassens]

Africa, difference proportional and absolute reduction:

Density: 1%

2.5%

5%

Land area: 1%

2.5%

5%

[jipclaassens]

It seems that 1% or 2.5% doesn't do so much. Whereas 5% has more impact, do you concur? @cjacobscrisioni

[cjacobscrisioni]

Looking at the absolute population densities in the Excel sheets, the 1% and 2.5% results are completely identical (just rounded differently here and there). Are you absolutely certain this is not an error, so that we can conclude that lowering pop reductions below 2.5% does not have any effect on densities?

[jipclaassens]

Sharp, let me see

[jipclaassens]

Updated. Was indeed a mistake in exporting

[cjacobscrisioni]

Thanks!!!! On the one hand, bigger percentages lead to bigger shifts in typologies (more new urban area specifically), on the other hand the loss of densities in urban areas is slightly less with bigger percentages. All in all, not the major impact we expected?

Follow-up question: what if we look at changes in population densities by 2020 degree of urbanisation?

[jipclaassens]

Africa, with DoU 2020: 1%

2.5%

5%

[jipclaassens]

Conclusion:

• the effect of 1% and 2.5% is quite similar. 5% not as much as we expected.
• in pre-existing urban areas, population densities increase, so the drop in urban densities is not an artefact of population reduction rules.