But you say that my neighborhood is __________ and it is much (more/less) diverse! Your analysis must be wrong!
The maps that we show on this site use a statistical model to estimate the trajectory that each neighborhood (census tract) likely follows. As with all statistical models, this one does not predict with 100% accuracy. It predicts within some tolerance of error, so it is conceivable that your neighborhood is one where the difference between the model and reality is relatively large.
What do you mean by "gradual succession"?
We mean that neighborhoods undergo slow, but steady increases in one racial group that makes them the dominant group in the neighborhood over time. Robert Park, probably the most influential urban sociologist in the world, described racial change as following the invasion/succession model of species from ecology (in fact, he argued that urban sociology should be studied as human ecology). The change he observed was often rapid, like White flight from a neighborhood. The process we observe is much slower -- hence the term "gradual succession."
Why do you think that gradual succession has replaced White flight?
We don't find much evidence of White flight after the 1970s. Instead, we suspect that what happens is that Whites happily integrate with neighbors who move into their neighborhoods; but, they don't look for integrated neighborhoods when they search for places to move (Mike has other papers showing this). Some Whites move out, not because they want to flee minority neighbors but because people get married, leave their parents' house, get new jobs, have kids and experience other events that lead to moves. The vacancies that they leave are typically not filled by Whites since most Whites don't look to move into neighborhoods with more than a few Whites (one exception might be quadrivial neighborhoods). Eventually, the White residents who remain get old (don't we all!) and then they pass away. Over time, the proportion of White residents declines and the minority population increases.
How did you choose the neighborhoods in your study?
We focused on the four largest cities in the United States and their surrounding suburbs for this paper. Those four cities -- New York, Los Angeles, Chicago, and Houston -- represent the four major regions of the country and they reflect a variety of racial change at the metropolitan level.
What are growth mixture models?
They are the statistical model that we used to identify types of neighborhood change. They group neighborhoods that have similar patterns of racial change across multiple groups. They are relatively new and require substantial computational power. This allows us to group neighborhoods by the timing and pace of change. Other studies typically only look at the the presence of groups, which they define as some percentage of the population. We can distinguish a neighborhood where, for example, the Latino population increases from 10% to 60% from one that increases from 10% to 15%. Other studies can't tell the difference between those two changes. For a more detailed description, please read our paper.
Do you have a list of which trajectory each census tract follows?
We do! You can find it on the GitHub repository here.
Can I share the information contained on this website?
Yes! We released the text and non-map images on this website under an Attribution-NonCommercial 4.0 International Creative Commons license. The underlying map data are copyrighted by the OpenStreetMap contributors and the map imagery is copyrighted by Mapbox. Static map images are available in the paper. Please contact us to share how you use this website!
If you use this website or underlying data for academic publications, please cite our paper:
Bader, Michael D. M., and Siri Warkentien. 2016. The Fragmented Evolution of Racial Integration since the Civil Rights Movement.” Sociological Science 3:135–166.
What tools did you use to create this website?
We constructed the website with several tools. We are indebted to the developers and maintainers of these packages. The maps are rendered with Leaflet, a JavaScript library for displaying geographic data on rendered tiles. We construct the graphs on this website using D3.js (Data Driven Documents), an excellent library to construct SVG formatted plots using JavaScript. On the backend, we used QGIS to construct the geographic files that the Leaflet engine renders.
I want to use growth mixture modeling for my own project. Can you help me with the method or the code?
Maybe. You should start by looking at the code that we have posted to the GitHub repository and we can help with basic questions. For more in-depth coverage, you may want to look at the resources from Mike's Growth Curve Modeling workshop including the GitHub repository for that workshop that contains example code.
But I don't see my question on this list!?
Feel free to contact us. We are happy to answer questions and will update this page as we get questions.