Headline Reach
96%· 973
of Londoners reachable by at least one intervention
Only 41 Londoners fall outside every lever tested
87%· 877
reachable by habit-building alone
The largest single addressable audience
80%· 808
reachable by two or more interventions
Layering, not choosing, is the default
41· 4%
genuinely unreachable by any lever
38 of 41 are Pragmatic Replacers
Intervention Types

Five levers, sized by responsive audience

Fixed
Identity layer · Values / Identity
Observable but not changeable. Shapes receptivity. Use it to read the audience, not to shift them.
Target
Behaviour layer · Habit-Building
The lever you can actually move. 877 Londoners (87%) are reachable. 823 are genuinely dormant — not blocked, just unprompted.
Channel
Channel layer · Tech / Digital · Peer / Social · Physical / Proximity
How you reach people and trigger action. Choice of channel depends on which persona you're designing for.
Intervention × Persona Matrix

Where each intervention lands, by persona

Each cell shows the responsive % for that intervention within that persona. Rank badges (top-right) indicate where the intervention ranks within the persona's five options. Cell shading intensity scales with responsive %, coloured by persona accent.

0% responsive
~80%
100%
Rank badge shows position within persona (1 = primary lever)
Pairwise & Three-way Overlap

Where multiple interventions share an audience

Overlap is where a single venture can cover more of London than any intervention alone. The three-way intersection identifies the core addressable audience for a layered venture; the pairwise cards below show the strategically significant two-way combinations.

Habit × Peer × Tech · the three-way core

Three channels that frequently co-activate. The zone where all three overlap is the largest single addressable core in the analysis.
Habit-Building 877 · 86.5% Peer / Social 639 · 63.0% Tech / Digital 507 · 50.0% 409 40.3% · all three 178 17.6% 46 4.5% 33 3.3%
409 Londoners (40.3%) respond to all three levers simultaneously. This is the core addressable audience for a venture stacking habit infrastructure with social activation and digital reach. The Accumulator is almost entirely within this group; roughly half of The Ethical Keeper and 40% of The Seasonal Clearer are also here. The Pragmatic Replacer (17%) is the gap — for them, habit-only is the primary route.
Persona n in 3-way % of cluster % of total
The Accumulator 15386%15.1%
The Pragmatic Replacer 7217%7.1%
The Ethical Keeper 6953%6.8%
The Seasonal Clearer 11540%11.3%
All three-way combinations, ranked

Four possible three-way intersections

Only one — Habit × Peer × Tech — clears 40% of London. The drop to the next combination is nearly half.

Rank 1 · Primary
Habit × Peer × Tech
409· 40.3%
Core addressable audience for a layered venture. Habit anchors action; peer and tech carry reach.
Rank 2
Habit × Peer × Values
210· 20.7%
Community + conscience. Values-framed peer-led rituals — deeper not wider.
Rank 3
Habit × Tech × Values
167· 16.5%
Digital transparency play. App-based cadence with ethical anchoring — smaller but retentive.
Rank 4
Peer × Tech × Values
165· 16.3%
No habit anchor — receptive but unlikely to move without cadence infrastructure.
Pairwise combinations

Five strategically significant pairs

Ranked by combined audience size. Circle size is proportional to each intervention's total responsive audience; visible overlap reflects the shared-audience n.

Bridge Audiences

Cross-cluster subgroups that unlock wider reach

People who respond to an intervention type outside of their "expected" cluster. These subgroups are why a well-designed intervention can be bigger than its primary persona suggests — and where a secondary cluster can be reached without changing the core design.

Comms Reachability Layer

Can we get a broadcast message to them at all?

Distinct from the intervention score above. The intervention score measures responsiveness to digital nudges; reachability asks the simpler prior question — does this audience sit on platforms where paid or organic broadcast reach is achievable? Share of each cluster on at least one of TikTok, Instagram, X, Facebook or Snapchat.

The Accumulator
94.9%
Broadcast reachable · 168 of 177
Instagram84%
Facebook63%
The Pragmatic Replacer
74.8%
Broadcast reachable · 317 of 424
Facebook56%
Instagram46%
The Ethical Keeper
79.8%
Broadcast reachable · 103 of 129
Instagram63%
Facebook56%
The Seasonal Clearer
81.3%
Broadcast reachable · 231 of 284
Instagram63%
Facebook57%
80.8%
All Londoners · 819 of 1,014
Broadcast reachable = uses at least one of TikTok, Instagram, X, Facebook or Snapchat — platforms where paid or organic reach is achievable. Distinct from the tech-digital intervention score, which measures behavioural responsiveness. The 14.4% reachable only via WhatsApp or Messenger can receive direct messages but are outside broadcast reach. Only 4.1% are unreachable via any digital channel.
Challenge Briefs

Four challenge briefs for the hack

Each brief merges intervention-stack sizing with qualitative anchors and a HMW question. The full brief document links the analysis on this page to the story in the synthesis.

View challenge briefs →

Methodology note · how responsiveness is measured

Each intervention type has a composite score built from 6–7 binary conditions drawn from the survey: disposal methods already in use, stated barriers, factor scores (RC1–RC7) from the Varimax-rotated PCA, and attitudinal signals. A respondent scores one point for each condition they satisfy.

Responsive is defined as a score of ≥2 (≥3 for habit-building, where the threshold is higher because the intervention specifically targets dormancy). This is the broad addressable audience. Strongly responsive is the core audience — ≥4 for tech, values and peer; ≥3 for physical; ≥5 for habit-building. Both figures are reported so the reader can see the difference between "potentially movable" and "obvious target".

Additionality is the test that matters most for venture design. For each intervention, we separate respondents who are already doing the target behaviour (selling online, using a collection bank, donating to charity, disposing at high frequency, passing clothes to friends/family) from those who are not. The incremental figure is the genuine new-behaviour audience — what the intervention would actually unlock. Where this number is small relative to the headline responsive count, the intervention is largely a capture play rather than a behaviour-change play.

Thresholds are deliberate and conservative. The responsive threshold is intentionally inclusive so total opportunity is visible; the strongly-responsive threshold narrows to the core. Both matter, and the gap between them — particularly inside the Pragmatic Replacer — carries real design information.

Intervention Conditions (1 pt each) Responsive Strongly Max
Tech / Digital
  1. RC1 > 0.3 (social/relational engagement above average)
  2. RC6 < −0.3 (resale-oriented)
  3. Influenced by social media or influencers
  4. Uses Instagram or TikTok
  5. Already sells online
  6. Buys via social media channel
≥ 2 ≥ 4 6
Physical / Proximity
  1. States "too far away" as disposal barrier
  2. States "can't be bothered" as barrier
  3. States "doesn't cross my mind" as barrier
  4. States "easier to just bin it" as barrier
  5. States "unsure where to go" as barrier
  6. Has clothes "bagged up but never donated"
  7. RC3 > 0.3 (above-average inertia score)
≥ 2 ≥ 3 7
Values / Identity
  1. RC4 > 0.5 (sustainability values factor above threshold)
  2. Sustainability signal count ≥ 2 (out of 5)
  3. Environmental or ethical concern drives purchase
  4. Environmental or ethical concern influences buying decisions
  5. Already donates to charity shop
  6. Primary mindset is "I rarely buy new clothes"
≥ 2 ≥ 4 6
Habit-Building
  1. Low disposal frequency band (yearly or less)
  2. RC3 < −0.1 (below-average inertia — dormant, not blocked)
  3. No active convenience barriers (can't be bothered = 0, too far = 0, easier to bin = 0)
  4. Seasonal clearout or wardrobe-full already triggers disposal
  5. Disposal orientation is proactive or mixed (not purely reactive)
  6. Uses at least one circular disposal method
  7. RC5 < −0.3 (small batch disposer — single items or handfuls)
≥ 3 ≥ 5 7
Peer / Social
  1. Already passes clothes to friends or family
  2. Friends/peers or "seeing others" influences buying decisions
  3. RC1 > 0.3 (social/relational engagement above average)
  4. Wardrobe-full or unworn-long-time already triggers disposal
  5. Uses Instagram or TikTok
  6. Has clothes "bagged up but never donated"
≥ 2 ≥ 4 6