RUNNING · GOAL

50 km in June.

one number to chase this month. below: how far i've actually run, where today's pace lands me by Jun 30, and a back-of-the-envelope probability that i make it.

0%Behind pace

estimated chance of reaching 50 km by Jun 30

7.2 / 50 km

day 14 of 30 · 16 to go

7.2 km

logged

2 runs · 2 days

15.3 km

projected finish

at 0.51 km/day

42.9 km

remaining

16 days left

2.68 km

need / day

now 0.51 km/day

CUMULATIVE DISTANCE

THE PREDICTION

each day of June is modelled as an i.i.d. draw of kilometres (rest days count as 0). from the 14 days so far i estimate a daily mean μ = 0.51 and std σ = 1.32. the remaining 16 days sum to S ≈ Normal(Rμ, Rσ²), so the chance of clearing the goal is the normal tail:

P(finish) = Φ( (R·μ − (G − C)) / (σ·√R) )

= Φ( (16·0.51 − 42.9) / (1.32·√16) )

= Φ(-6.59) = 0%

a rough estimate, not a guarantee — it assumes the rest of the month looks statistically like the start of it. early in the month, with few data points, σ is large and the number swings easily.

RUNS · JUNE

Jun 7Road work4.1 km6:42 /km

Jun 3evening run3.0 km6:14 /km

synced from a free Strava data export — no API, no subscription. drop activities.csv at data/strava/ and run node scripts/parse-strava.mjs to refresh.