A small-town economy you build lot by lot: logistic population, job matching, a circular flow of money and a mood score from real needs. Illustrative numbers.
Click a lot on the map.
Outside income of +$2 per resident per day is injected; the lab compares the measured rise in household income with the closed-form multiplier 1/(1 - w c (1 - t)).
The science
Population. Residents follow a logistic law capped by housing K: dP/dt = r P (1 - P/K) A + m A (K - P). A in [0,1] is attractiveness (mood and job availability). With m = 0, A = 1 it has the closed form P(t) = K / (1 + ((K-P0)/P0) e^(-rt)); the page checks the integrator against it.
Jobs. Hiring uses a Cobb-Douglas matching function h = mu U^a V^(1-a) (U unemployed, V vacancies) minus separations s E. Steady state solves mu (L-E)^a (V-E)^(1-a) = s E.
Circular flow. Workshops and offices sell to the outside world (the economic base); wages become household income Y; households pay rent, keep 1-c as savings and spend c locally on food, leisure and goods. Local shops only staff what demand needs, so extra income raises local jobs again: Y = (X_w + bP - w c R) / (1 - w c (1-t)) where w is wage cost per dollar of local sales. This is the Keynesian / base-multiplier idea; when spending is capped by visits per resident the multiplier is exactly 1.
Ledger. Every tick the money identity dPlayer + dHouseholds + dCivic = Exports - Upkeep + Outside income is verified (shown below the checks).
Mood. A weighted score of job coverage, food, leisure, goods, affordability, civic services (tax revenue per resident) and housing. Free leisure comes from parks and the plaza.
Simplifications. One owner owns everything; all prices, wages, costs and visit rates are illustrative game values, not statistics. Construction wages are not fed back into incomes. No inflation, no credit, no land market. The town, shop names and the person are generic and fictional. The 3D art was modelled and texture-baked in Blender; the clock tower shows game time.
Made with Blender and Three.js. Fictional town; not affiliated with any game or brand.