> In the case of murder, the murder rate today is no higher than it was a century ago and much less than it was 30 years ago.
To make that claim, you need to define "rate". Does "rate" mean the absolute number of murders per day or year, or the number of murders per day or year divided by the population?
The absolute rate is obviously higher -- the burden must be is yours to offer evidence that it's unchanged since 1800. But the rate per population might be unchanged (not likely), but if so, that supports the idea that increased population is a factor, which circles back to my original point.
Also, when you perform a moving average, you can "prove" anything by choosing the right interval. But, because the future is expected to be long, so should our averaging interval. To do otherwise is intellectually dishonest.
For example, climate change deniers use short averaging intervals to "prove" that the climate is actually cooling, where the same measure using a longer averaging interval shows this is false.
Oh, I see you do just that. Too bad -- choosing an inappropriate averaging interval is not science, it's politics.
> ... population growth means we expect more incidents even if the base rate were flat or declining.
Well ... now that you're arguing my points for me, I guess we're done.
"rate" means per capita per year. By "a century ago" I meant around 1913; 1800 would be TWO centuries ago. The murder rate in the US has been in the general ballpark of 5-10 per 100,000 annually since 1910. Currently we're near the low point of the last century. Um, here:
Quote: "Today's murder rate is essentially at a low point of the past century. The murder rate in 2011 was lower than it was in 1911. And the trend is downward. Whatever we've been doing over the last 20-30 years seems to be working, more or less. The murder rate has been cut by more than half since 1980: from 10.7 to 4.7."
> But the rate per population might be unchanged (not likely), but if so, that supports the idea that increased population is a factor, which circles back to my original point.
You now appear to be stark raving bonkers. No, silly, if the rate is unchanged it does NOT support your point. Yes, as there are more people, there are likely to be more murders as an absolute number. There are also likely to be more hugs, more kisses, more birthday parties, and more people making silly arguments over the internet. NONE of those constitute a population-limiting crisis.
That's by no means the only meaning of "rate". The meaning of a rate depends on the two values involved -- the dividend and divisor. The identity of both defines a specific use of the term "rate".
"Murders divided by years" is one example of a rate.
"Murders divided by (years times population)" is another.
And "(mb-ma) divided by ((yb-ya) times (pb-pa))" starts us toward a moving average.
Rate doesn't have only one meaning -- to accept your definition would severely constrain mathematics.
> No, silly, if the rate is unchanged it does NOT support your point.
Of course it does -- given a rapidly increasing population and the same rate, it means the absolute number of incidents has increased. That was my point.
> There are also likely to be more hugs, more kisses, more birthday parties, and more people making silly arguments over the internet. NONE of those constitute a population-limiting crisis.
But in truth, all of them do. It's a classic case of an increasing population held within a finite land mass -- eventually the system collapses.
If the population is increasing without constraint, it doesn't matter what those people are doing apart from increasing their numbers -- the fact that they're increasing their numbers eventually becomes the only issue worth addressing.
A "murder rate", being a fair bit smaller, is almost always expressed per 100,000 people per year.
> If the population is increasing without constraint
It isn't. Population growth rates have rapidly declined all over the world. The US population would already be shrinking were it not for immigration. Even Bangladesh and India are currently reproducing at right around replacement levels.
> It is the standard definition when talking about a CRIME rate.
That wasn't your claim, and it's false in any case. There's no standard definition of "rate" -- you need to define your terms, and "rate" means a measure of change, not any specific measure without additional information. In any case, the exchange below tells me that you really don't understand what "rate" means.
>> If the population is increasing without constraint
> It isn't. Population growth rates [emphasis added] have rapidly declined all over the world.
Honestly. I say population is increasing. You reply by saying that the "growth rate", i.e. the first derivative of population, has declined. Both are true. To sort this out, take Calculus. Until you understand the difference between a function and its first derivative, we won't be able to discuss this issue.
No. What you said was that population was increasing without constraint. It's that last bit I was responding to.
The fact that the rate of growth is declining does suggest the presence of one or more constraints, even if the overall growth rate hasn't quite reversed just yet. The primary form of the constraint appears to be that as childhood survival rates and living standards improve, families voluntarily choose to have fewer kids. This is happening all over the world, there's no reason to think it will stop any time soon, and it argues against your implication that "mass death" is the only likely way out.
(For what it's worth, I have taken calculus. And if you're the guy who wrote AppleWriter: Nice job! I liked that program. I used it in high school.)
> The fact that the rate of growth is declining does suggest the presence of one or more constraints ...
Yes, or more likely, it's a random fluctuation indicative of nothing in particular. The latter assumption, which may seem overly skeptical, is how a scientist is expected to look at an unexplained change in the rate, based on a precept called the null hypothesis -- a presumption that (in a manner of speaking) it's all random and meaningless.
> ... and it argues against your implication that "mass death" is the only likely way out.
Not really. Remember that nature efficiently picks out those with the highest birthrates and makes them the entire future population. My point is that population growth is naturally unstable, depending only on food sources and a willingness to push other species out of the way.
1.1% per annum may not seem like a very large rate of increase, but 63 years doesn't seem like a very long time to double the world's population either.
Exponential increases of all kinds are rather scary to model. They're scary enough when one looks at compound interest and how that naturally creates a chasm between rich and poor over time, but the "big show" for exponential increases is population, where much more is at stake.
> For what it's worth, I have taken calculus.
Okay, glad to hear it. Given that, I think you will appreciate what I thought when I heard you object that population couldn't be increasing because the rate of increase was decreasing.
> And if you're the guy who wrote AppleWriter: Nice job! I liked that program. I used it in high school.
>Yes, or more likely, it's a random fluctuation indicative of nothing in particular. The latter assumption, which may seem overly skeptical, is how a scientist is expected to look at an unexplained change in the rate, based on a precept called the null hypothesis
It's NOT UNEXPLAINED and it's NOT RANDOM.
Does your browser support Flash? If I point you at a chart composed using gapminder.org could you please please LOOK AT IT? (Or if you can't, could you let me know what the constraints are on what your browser can see, so I can find another way to get you the information?) The link will follow this paragraph. Press the "play" button below this chart to see an animated plot of fertility versus child mortality. Several specific countries are hilighted - you see a trail of their progress over time - but the ENTIRE MASS of countries follows much the same pattern - it moves down and to the left. Here's the link:
It truly boggles my mind that you could think even for a second that the slowdown in population growth is "likely a random fluctuation indicative of nothing in particular". It is a TREND. The phenomenon is quite consistent. Across the ENTIRE PLANET, countries are increasing their GDP, decreasing child mortality and decreasing the rate at which they have kids, with all those changes roughly in tandem. And it's not a random walk where one needs to cherry-pick any specific interval to see these trends - if you just look at the entirety of ALL the data we have available and plot it, you can see a consistent movement.
Please look at the animation. Play around with it - use the checkbox list on the right to highlight other specific countries. Get a sense of what the data is actually DOING before you claim it's a random fluctuation.
A random walk WOULD be susceptible to cherry-picking - the trend would only show up if you pick certain time ranges or certain sets of countries.
This is not that.
(Given current trends, the world population would not double again - it would stop growing short of that.)
To make that claim, you need to define "rate". Does "rate" mean the absolute number of murders per day or year, or the number of murders per day or year divided by the population?
The absolute rate is obviously higher -- the burden must be is yours to offer evidence that it's unchanged since 1800. But the rate per population might be unchanged (not likely), but if so, that supports the idea that increased population is a factor, which circles back to my original point.
Also, when you perform a moving average, you can "prove" anything by choosing the right interval. But, because the future is expected to be long, so should our averaging interval. To do otherwise is intellectually dishonest.
For example, climate change deniers use short averaging intervals to "prove" that the climate is actually cooling, where the same measure using a longer averaging interval shows this is false.
Oh, I see you do just that. Too bad -- choosing an inappropriate averaging interval is not science, it's politics.
> ... population growth means we expect more incidents even if the base rate were flat or declining.
Well ... now that you're arguing my points for me, I guess we're done.