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Sharing insights from the intersection of geospatial data science and economics | PhD in Economic Geography from @lsenews. Views are my own.
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Jun 19 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: Image 1. Meta provides granular estimates of household wealth for low and middle income countries.

Read more about it here:
Jun 17 9 tweets 5 min read
It can be a nightmare to find official sub-national shapefiles.

Luckily, there are a number of sources that make the job easier: Image 1. GADM

The most widely used source of global shapefiles is the Database of Global Administrative Areas (GADM).

For countries like the UK, it provides boundaries down to the admin 4 level.

Link: gadm.orgImage
Jun 16 13 tweets 4 min read
One of the biggest traps in geospatial analysis?

Ecological Fallacy.

It can turn a map into a misleading story.

Here's what you need to know about it: Image In simple terms, ecological fallacy is drawing conclusions about individuals from data that were aggregated over areas (e.g. counties, districts, grids). Source: ScienceUpFirst
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. Image 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. Image
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: Image Back in 2016, Stanford's AI Lab pioneered a new method of measuring economic activity using daytime satellite images. Image
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: Image 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? Image
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: Image 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’. Image
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: Image 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.

link: geo.aiddata.orgImage
May 9 12 tweets 3 min read
Air pollution is a massive problem.

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: Image 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. Image
May 5 14 tweets 3 min read
Rivers are shrinking.

This is happening because water is leaking into the ground.

Here's the breakdown: Image 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. Image
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: Image A new study in Nature Communications, analyses geocoded DHS data (RIP😢) at a 5km resolution.

It highlights serious concerns for health and development policymaking: Image
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: Image 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. Image
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: Image 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. Image
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: Image 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: Image 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. Image
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: Image @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: Image
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: Image 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: Image Google has developed a new AI-powered weather forecasting model called NeuralGCM.

It combines traditional physics-based prediction methods with machine learning. Image
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: Image 1. Meta provides granular estimates of household wealth for low and middle income countries.

Read more about it here:
Jan 24 8 tweets 3 min read
We can now easily access over 18,000 geospatial datasets instantly, for free.

Here's everything you need to know about the Geospatial Data Catalog: Finding the right geospatial dataset can be incredibly frustrating.

We sift through Google Earth Engine, Humanitarian Data Exchange, etc, only to come up empty-handed.

We'll often conclude the dataset we need simply doesn’t exist.
Jan 17 14 tweets 4 min read
Did you know we can access 𝙙𝙖𝙞𝙡𝙮 geospatial climate projections up until 1 Jan 2100?

It covers projections for:
• temperatures
• precipitation
• wind

Plus it's completely free.

Here's what you need to know about it: Image Daily geospatial scenario-based climate projections are part of the CMIP initiative.

CMIP is a framework for research centres across the world to develop standardised climate projections. Image