If Verhulst's growth model was valid, why didn't the United Nations take it into consideration in the 1970s, when it was jumping up and down telling us the sky was falling? The reason is that the formula didn't hold weight back then. I don't think it does now. What use is it if you have to continually insert qualifiers.
What you are basicly saying is that it's a fabulous model as long as we can insert the "unknown factor" whenever it doesn't reflect reality. Here's the unkown factor for the US. Here's the unknown factor for China. Here's the unkown factor for Europe. Here's the unknown factor for the Middle-East. And here's the multi-faceted unkown factor for the planet. I have a rather strong suspicion that this formula is always going to be recognized by some people as extremely accurate after the fact, but will never be the stuff of an accurate predictor.
In one of my replies I made the observation that this planet's populace is still increasing at the rate of 100 million per year. In eighteen years that will be 1.8 billion. Add 1.8 billion to 6.2 billion and you have 8 billion. That's reality. I don't think the Verhulst growth model has exhibited it's reliability.
You can't be serious. I actually had to look to see if you were a newbie. You are not. You've been here a long time, so you must know that the UN is completely motivated by politics. The UN has NOT been using this model, they have been using a simplistic exponential growth model (which has been my unstated point all along). That way they could inflate their population projections so that they can "save the world" with their socialist environmental, economic and anti-Christian population control policies. And the left has used "population explosion" as a justification for any and all of their pet projects. It has been the mathematicians and biologists who have been jumping up and down trying to tell us that the UN is wrong. Remember Paul Ehrlich? He was a California pseudo-scientist that was trying to sell a lot of books and make a name for himself. Using the UN exponential growth models, he stated in 1970 that the world population would be so great by 2000 that society wouldn't be able to function
What you are basicly saying is that it's a fabulous model as long as we can insert the "unknown factor" whenever it doesn't reflect reality.
No, these are factors applied to the specific population set that is of interest. In 1845, Verhulst predicted the 1930 population of his home country, France, to within a percent. In 1920 Pearl and Reed (Proceedings of the National Academy of Sciences, 1920, p275) predicted the 1950 population of the United States to within 1.1% accuracy, despite unforseen waves of immigration and several major wars.
In one of my replies I made the observation that this planet's populace is still increasing at the rate of 100 million per year. In eighteen years that will be 1.8 billion. Add 1.8 billion to 6.2 billion and you have 8 billion. That's reality.
No, that's the crap that the UN has been selling for decades, and you've bought it hook-line-and-sinker, like the rest of the sheeple. If you'd stop being so stubborn, you'd free yourself from the need for a socialist UN "savior". The linear model that you suggest is only accurate for very short term projections, maybe a year or two. You can accurately predict that next year's population will be 100 million more than it is today, but beyond that you would be overestimating badly. It is incredibly pessimistic for long term projections.