Here's what you need to know about it:
In simple terms, ecological fallacy is drawing conclusions about individuals from data that were aggregated over areas (e.g. counties, districts, grids).
Jun 6 • 13 tweets • 3 min read
What happens when a scientist pays $300 for 50 citations?
A study reveals a growing black market of citation mills, and why it threatens the credibility of science.
To test the Google Scholar system, researchers created a fake academic and paid $300 to buy 50 citations.
Within 40 days, citations started appearing in Google Scholar, published in journals with impact factors as high as 4.79.
Jun 3 • 12 tweets • 4 min read
We track poverty too slowly to respond effectively.
But a new open-source tool now lets us map wealth in near real-time using satellite imagery.
Here’s what you need to know:
Back in 2016, Stanford's AI Lab pioneered a new method of measuring economic activity using daytime satellite images.
Jun 2 • 13 tweets • 3 min read
If your regression results look great but perform poorly in some areas, there could be a cause:
Spatial nonstationarity.
It’s one of the most overlooked issues in spatial analysis.
Here’s what it is and how to detect it:
Imagine you’re studying how income affects house prices in a city.
You run a regression and get a single coefficient.
E.g., every $1,000 increase in income raises house prices by $5,000.
But is that true everywhere in the city?
May 16 • 11 tweets • 4 min read
Satellite data is being used to detect marine litter from space.
Here's everything you need to know about it:
A new paper in @NatureComms describes a novel way of detecting marine litter using satellite images.
They use data from Sentinel-2 to detect ‘litter windrows’.
May 12 • 12 tweets • 6 min read
Geospatial data science is all about having access to good data.
Here are a list of my favourite free geospatial resources: 1. Aiddata
Aiddata has an excellent list of geospatial datasets.
It's all available as a CSV.
So you don't even need to know GIS to access their data.
However, it's incredibly difficult to work out WHERE it comes from.
A new study has compiled over 34,000 measurements from 66 countries to trace its sources:
Researchers developed a blockchain-based isotopic database, compiling 34,815 isotopic fingerprints from 1,890 pollution events across the world.
It covers data from 1957 to 2023.
May 5 • 14 tweets • 3 min read
Rivers are shrinking.
This is happening because water is leaking into the ground.
Here's the breakdown:
A new study published in Nature Communications, analyses over 17,900 wells across Brazil.
It aims to understand where rivers may be losing water into aquifers.
May 1 • 13 tweets • 4 min read
Most people assume national household surveys are uniformly high quality.
But a new study finds massive subnational differences in data quality across 35 African countries.
Here's the breakdown:
A new study in Nature Communications, analyses geocoded DHS data (RIP😢) at a 5km resolution.
It highlights serious concerns for health and development policymaking:
Apr 14 • 14 tweets • 5 min read
We're constantly told how countries are run by the elites.
However, mapping the economic elite has been incredibly tough to do.
But now, a new dataset compiled by 70+ researchers provides data on over 3,500 elites in 16 countries:
In the 19th century, many countries — particularly in Europe, were run by the aristocracy.
Fast forward to today, most monarchs (if they’re still around), are mainly ceremonial figures.
Mar 24 • 22 tweets • 6 min read
To do good research, you need good tools.
Here are the (free) tools I can't live without:
𝟭. 𝗧𝗼𝗽𝗶𝗰 𝗜𝗱𝗲𝗮𝘁𝗶𝗼𝗻
The first category of tools I use is for ideating on a topic.
Nothing fancy here.
I use OpenAI models to brainstorm research ideas.
Mar 6 • 13 tweets • 4 min read
Meta is using Facebook and mobile phone data to produce super-granular household wealth estimates.
Here’s what you need to know about the Relative Wealth Index:
The Relative Wealth Index (RWI) is a geospatial measure, which shows wealth disparities within countries.
Main features:
• It's open source
• It measures 'asset-based' wealth
• It covers 135 countries in the world
• Data is provided at 2.4km resolution
Mar 4 • 15 tweets • 4 min read
In 1969 a husband and wife launched a geospatial company with $1,100.
Today that bootstrapped company makes annual revenue over $1.5 billion.
Here’s the story of ESRI:
Jack Dangermond, studied environmental science and landscape architecture at Cal Poly.
In 1969, after a stint at Harvard, together with his wife Laura, he set up a consulting company in California.
They called it the Environmental Systems Research Institute—ESRI.
Feb 21 • 16 tweets • 5 min read
Measuring agricultural GDP at a pixel level is notoriously challenging.
It requires precise information on crop type and crop yield.
@esa has launched a (free) dataset that provides this information.
Here's what you need to know about it:
@esa ESA's WorldCereal project launched a dataset that provides data:
• at 10m resolution
• on farmland
• on seasonal maps of maize and cereals
• on where irrigation is used during different seasons
• on annual maps for where crops are grown temporarily
Let's unpack:
Feb 17 • 21 tweets • 5 min read
Geospatial foundation models are all the rage these days.
But, are they all hype and no substance?
Let's take a look:
If I could sum up geospatial data science in 2024 in just two words, it’d be “foundation models”.
Last year saw the release of numerous geospatial foundation models (GFMs) like:
• NASA and IBM’s Prithvi,
• SpectralGPT
• Satlasnet
• AnySat
• Clay
Feb 14 • 13 tweets • 4 min read
Google is changing the weather forecasting game.
Plus they've created a Python library to make their model available.
Here's what you need to know about it:
Google has developed a new AI-powered weather forecasting model called NeuralGCM.
It combines traditional physics-based prediction methods with machine learning.
Jan 28 • 12 tweets • 5 min read
Meta is known for Facebook, WhatsApp and Instagram.
But did you know they provide a range of free geospatial datasets for researchers?
These include granular measures of household wealth, population, and network access.
Here's what you need to know about it: 1. Meta provides granular estimates of household wealth for low and middle income countries.