PostcodePremium.GIS is an interactive mapping tool for visualizing UK property price premiums normalized against different geographical levels.

• Prices: All prices are given in £/m² (NOT per transaction).
• Dataset: The dataset contains all market price residential property sales from 2019.

How It Works

• Each map (area | subarea) shows the mean price in each subarea, discounted by the mean price in their respective areas. For example, 'Regional | MSOA' shows the mean price per 'middle layer super output area', discounted by the mean price in their respective regions.
• The exception to this is that 'Total | Area' maps such as 'Total | LSOA' give the absolute mean prices, not discounted by the national average.

Heatmap Styles

• Premium: Shows absolute premium values in £/m²
• Z-Score: Represents premium normalized by the map's mean and standard deviation

Confidence & Statistics

• Confidence: Can be seen by hovering your mouse over the map. It represents the chance that the difference in the data between one subarea and its surrounding area is not a coincidence. Sample size and extreme differences increase confidence. It is derived from Student's t-test.
• Mean: Represents the national mean price.
• R: Represents the average correlation of premium within each subgroup.