Life as Clay

Posts Tagged ‘Public Health

Performance of a free niche app in the Mac App Store

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I released the free Population Pyramid Generator in the Mac App Store at the end of last week. The tool is very simple. I tried to make sure that it was stable and that it does what it claims to do without trouble. I think that I succeeded on those fronts. There certainly is room for improvement, however, and I have plans to add several features in a forthcoming revision.

My expectations upon release of the application were that maybe 50-60 people would download it. Let’s be honest: it’s a niche tool, and while useful for people who need a population pyramid, it’s pretty useless to anybody else. Part of my motivation to create it was that my business website receives a lot of hits related to population pyramids because I wrote a blog post there about them. I thought that it would be nice to provide the tool and that it potentially could help me find additional clients.

What I didn’t expect is that aggregation sites like would pick up the app. It turns out that a lot of people are exposed to it through those sites. It’s appearance in Google rankings received a quick boost and traffic to my company’s website skyrocketed shortly after the app became available.

In the first 5 days, the Population Pyramid Generator was downloaded nearly 450 times — ten times my expectation. It went live around 4pm EST on 02/24.

Equally surprising was the breakdown by country. This view shows only the first 4 days (due to the week cutoff in the itunesconnect interface):

Considering that I did basically zero marketing of this app, what’s the lesson here? I think that simple free tools, especially ones that fill an unmet niche, can be relatively effective marketing tools for a business. All told, it took me ~ 1.5 weeks to build the Population Pyramid Generator. As people with need for such a tool find and download it, perhaps I’ll gain an additional client or two. That would be worth the time investment alone. In fact, the increase in Google rankings following the release of the app probably make it worth the time investment.

The Population Pyramid Generator is a fun experiment for me and I look forward to adding additional features to it, as time allows. I also plan to create a similar tool for Windows (and use it as a project to teach myself .NET and C#).


Written by Clay

March 1, 2011 at 08:40

DC as seen through population pyramids

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All of the recent work on parsing US Census data was part of a larger project — one that includes the dynamic generation of population pyramids for the entire population and for selected racial groups within each county in the United States. Residents of DC (like myself) frequently hear about how it is a terrible place for young women to meet boyfriends and date successfully. All data here are from the 2009 US Census Bureau population estimates.

Here’s what the population pyramids show:

For the final one, keep in mind that “Hispanic” is considered an ethnicity by the US Census Bureau and that most Hispanics also select a race on census forms and most people who select a race also indicate whether they also consider themselves Hispanic.

What really is striking here is the difference between the shapes of the white and black population pyramids. Perhaps a lot of young white people move to DC for congressional jobs and then move away when the job is finished. DC traditionally has a larger permanent black population and that is reflected in the more even distribution of the pyramid. However, DC also is known for having one of the least healthy black populations in the country, a fact reflected in the low numbers of elderly people. For comparison, look at this view of whites in Palm Beach, Florida:

Back to the original question — yes, you can see in the population pyramid that there are more females than males in Washington, DC, except in the population that identify as being ethnically Hispanic. Where do you go to find the opposite problem? One place is Honolulu, Hawaii:

Only Native Hawaiians (a group including other Pacific Islanders) show a normal distribution:

(All of these population pyramids were generated using CSS in a custom script written in Ruby on Rails.)

Written by Clay

July 26, 2010 at 12:40

Population Generator

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Well, I’ve been away, working on a larger project. It’s less artsy but more practical towards my interests in simulation. Interestingly, it takes only mild deviations away from the world of data art to begin to realize the limitations of Processing. (That’s not entirely fair: Processing can import and use Java libraries, so there is more available that I currently am using. I have not, however, played with importing other libraries yet.)

I created a population generator that randomly generates a population of a specified size. It then displays 4 random members of the population above the demographics of the population. Clicking (can’t do it here, on the image….) rotates different members of the population into the slots above the demographics. Age 18 is considered full grown. People under 18 are displayed relative to the size of a full adult, scaled based on their age. Eventually, I will build in variation for height, weight, and other demographics. The colors of their shirts are randomly generated when they are created, but the tone of the skin on their head is randomly chosen from only 3 colors.

The demographics display is a technique used frequently in public health and demography, called a population pyramid. I think mine is upside down, but that’s an easy fix. In fact, I already fixed it in the code, but didn’t want to take a new screenshot. :)

So, why do this? My hope is to be able to create digital populations of people that I can use to simulate a variety of things related to public health, disease, and complex emergencies. That’s a long way down the road, but I think that I’ve done pretty well for the two days that I’ve spent working on it so far — especially for a programming newbie!

This definitely remains a work in progress, but this is what it currently looks like:

Population Generator

Written by Clay

November 5, 2009 at 22:03