Same pattern: what rises and falls with cafés across London

What rises and falls with cafés in London?

Across London, three measures follow the pattern of cafés within a 10-minute walk very closely: all restaurants, shopping, and beauty & spa places, each within a 10-minute walk too. Where one is high, the others are high; where one is low, so are they. One measure goes the other way: the owner-occupier share, which tends to be low where cafés are many. The card that says so is Same pattern, and it opens from any factor of a Score.

It compares the order of London's hexes - hexagons about 350 m across - on two measures at once: rank every hex on each, and see how well the two rankings line up. The field calls that Spearman's rank correlation. The app never shows the number; it says it in three words.

Same patternthe field's term: Spearman's rank correlation

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The idea, in one sentence

Put every hex in order on one measure, then on the other: the more alike the two orders, the more closely the measures follow one pattern. The answer comes in three strengths, plus one line for the opposite:

Where to click

Open a Score. In its Selected settings panel, above the factor cards, sits the importance bar: one colored piece per factor, as wide as that factor's share of the Score. Tap a piece, and the card for that factor opens.

Every row on the card does something:

• The ＋ adds that measure to your Score as a new factor, read the way it was compared - here, within a 10-minute walk. A measure already on your Score says on your Score instead.
• Tapping a row's name opens Cross two with the factor and that measure, so you can see the two patterns side by side, hex by hex.
• On a factor that adds several kinds together, a last section, Inside this factor, says which of its own kinds follow one pattern.

When two factors of one Score follow one pattern very closely, the importance bar says so by itself: a small bracket appears under their two pieces, labeled same pattern ›. Tap it and the card names the pair, with See them together › to open them on Cross two.

Two more places it shows up

While you add factors. Press Add measures on a Score and, above the usual list of measures, a card titled Same pattern as your Score in London suggests up to three measures that rise and fall with a factor you already have and are not on your Score yet. Each row says which factor it follows.

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That last row is worth a second look. Same pattern states facts, not discoveries, so the obvious ones are listed too. A measure worked out from another - population density from population - can follow it very closely for that reason alone.

On Cross two. Open the second-measure picker of a Cross two map, and the top of the list reads Same pattern as … your first measure, with up to three rows and the one that goes the other way. Picking a row draws it as the second measure.

The math, honestly

Rank correlation needs only the order of the hexes, never their values. The five hexes below are illustrative - the shape of the sum is exactly what the app does.

The words come from fixed cut-offs, the same for every city and every measure:

• 0.8 or more - very closely (and the bracket, between two factors)
• 0.6 to 0.8 - closely
• 0.4 to 0.6 - somewhat
• −0.4 or less - goes the other way

Why ranks rather than the values themselves:

• Units stop mattering. A count and a share, a total and a rate are compared on where they are high and where they are low.
• One extreme hex cannot decide it. A handful of central hexes with dozens of cafés would sway a correlation of raw values; ranked, they are simply the top few.

Each list takes one measure per topic - one category of place, one census topic - so it is not five kinds of restaurant in a row. A measure with a value in fewer than 30 hexes gets no list, only one sentence: “Only [N] hexes in [city] have a value for [measure], so what follows the same pattern can't be told apart from chance.”

Try it on the series' Score

The link opens the Score this series uses throughout: cafés and transit stops within a 10-minute walk, plus the residents of each hex. Tap the Café piece of the importance bar, then the Total population piece, and compare the two cards. For what each factor does to the Score, see how the Score works; for what stands near a kind of place rather than what rises with it, see Usually nearby.

Open the Score in London

The whole idea, in six lines

• Same pattern ranks every hex on two measures and checks how well the two orders line up - Spearman's rank correlation.
• The number is never shown: very closely (0.8 or more), closely (0.6), somewhat (0.4), and Goes the other way (−0.4 or less).
• Tap a piece of a Score's importance bar to open the card for that factor; a same pattern › bracket joins two factors that follow one pattern very closely.
• ＋ adds a listed measure to your Score; tapping its name opens the pair on Cross two.
• It also suggests measures under Add measures and tops Cross two's second-measure picker.
• It states where things are high and low together - never a cause, never advice.