{"uid":"cap__T0yj8kvYVYEdlgwsQDsj","slug":"halowerk-price-elasticity-estimator-0e998044","name":"HALOWERK Price Elasticity Estimator","description":"Fits a constant-elasticity demand curve to the price and sales series you supply and returns the elasticity with its standard error, t statistic, two-sided p value and a Student t confidence interval, not a normal one, because at eight observations the difference in interval width is double-digit percent and a too narrow interval is exactly the kind of number a machine reuses unchecked.","url":"https://handel.halowerk.com/v1/price-elasticity?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"currency":{"type":"string","default":"EUR","maxLength":3,"minLength":3,"description":"ISO 4217 code for every amount in this request. Not converted, only carried through."},"unit_cost":{"type":"number","maximum":100000000,"minimum":0,"description":"Variable cost per unit. Required for the contribution-optimal price; without it only the elasticity is returned."},"price_grid":{"type":"array","items":{"type":"number","maximum":100000000,"exclusiveMinimum":0},"maxItems":200,"description":"Candidate prices to evaluate with predicted units and contribution. Evaluated at the fitted model, in the order you give them."},"observations":{"type":"array","items":{"type":"object","required":["price","units_sold"],"properties":{"price":{"type":"number","maximum":100000000,"description":"Selling price in that period. Must be positive: the estimation is on logarithms.","exclusiveMinimum":0},"promotion":{"type":"boolean","default":false,"description":"Whether the period was a promotion. Enters the fit as a separate indicator when include_promotion is true, so that a campaign is not attributed to the price."},"units_sold":{"type":"number","maximum":1000000000,"minimum":0,"description":"Units sold at that price. A zero cannot enter a log-log fit and is excluded, reported and never silently dropped."},"period_start":{"type":"string","pattern":"^\\d{4}-\\d{2}-\\d{2}$","description":"Optional period label as YYYY-MM-DD, passed through unchanged."},"competitor_price":{"type":"number","maximum":100000000,"description":"Competitor price in that period. Only used when include_competitor_price is true; you bring the figure, nothing is looked up.","exclusiveMinimum":0}},"additionalProperties":false},"maxItems":2000,"minItems":4,"description":"Your own price and sales history for one SKU. Every amount is in the currency named at document level."},"confidence_level":{"enum":[0.8,0.9,0.95],"type":"number","default":0.95,"description":"Confidence level for the elasticity interval. Student t, not normal."},"include_promotion":{"type":"boolean","default":false,"description":"Whether to add the promotion indicator as a regressor."},"include_competitor_price":{"type":"boolean","default":false,"description":"Whether to add the log competitor price as a second regressor and report the cross-price elasticity. Every observation must then carry competitor_price."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_GyODDEdAtB0ly8xEj5NJ-","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fits a log-log (constant-elasticity) demand curve to historical price and sales data and returns elasticity, standard error, t-statistic, p-value, and Student-t confidence intervals, plus optional contribution-optimal price and price grid evaluation.","exampleAgentPrompt":"Using my sales history for our coffee capsule SKU — 8 weekly observations at prices between €4.50 and €7.00 with units sold ranging from 320 to 890 — fit a constant-elasticity demand curve and tell me the elasticity, its 95% Student-t confidence interval, and the contribution-optimal price given a variable unit cost of €1.80.","exampleUseCases":[{"title":"Retailer repricing a seasonal product","prompt":"I have 12 months of monthly price and units-sold data for our winter jacket line, prices ranged from €89 to €149 and volume from 40 to 310 units, with three of those months flagged as promotional campaigns. Fit an elasticity model controlling for promotions and tell me the elasticity at 95% confidence — currency is EUR."},{"title":"Category manager evaluating a price ladder","prompt":"We're considering five price points for our private-label pasta — €0.79, €0.89, €0.99, €1.09, and €1.19 — and I have 8 quarterly observations of actual sales. Our unit cost is €0.35. Can you fit the demand curve and tell me which of those five prices maximizes contribution margin, along with the elasticity and its confidence interval?"},{"title":"Startup stress-testing demand sensitivity","prompt":"We ran a pricing experiment across 6 cities at different price points between $12 and $28 for our SaaS monthly plan, here are the subscriber counts for each. Fit a log-log demand model, give me the elasticity with its standard error and p-value at 90% confidence, and tell me if demand is statistically significantly elastic."}],"resultDescription":"Returns the estimated price elasticity coefficient, its standard error, t-statistic, two-sided p-value, and a Student-t confidence interval at the requested level. If unit_cost is provided, also returns the contribution-optimal price. If price_grid is provided, returns predicted units sold and contribution margin at each candidate price. Zero-unit observations are excluded and reported explicitly rather than silently dropped.","failureModes":["Fewer than 4 observations supplied — minimum required for a meaningful fit","All prices identical — log-log regression requires price variation","Zero units_sold in all periods — no non-zero observations to fit","Negative or zero prices supplied — logarithm is undefined","Insufficient degrees of freedom for requested confidence level","Competitor price or promotion flag provided but corresponding option flag not enabled in request","Currency code not exactly 3 uppercase ISO 4217 characters","Payment not confirmed via x402 — 402 Payment Required returned"],"whenToPreferThis":"Choose this endpoint when you need a statistically rigorous, constant-elasticity demand estimate backed by Student-t (not normal) confidence intervals — especially critical at small sample sizes (under ~30 observations) where normal approximations meaningfully understate uncertainty. Prefer it over manual regression when you also need promotion-period controls, competitor price controls, a contribution-optimal price recommendation, or evaluation of a candidate price grid, all in a single call. It is purpose-built for single-SKU pricing analysis from your own historical data, not for cross-sectional market research or real-time demand signals.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-10T06:32:03.611Z","isFirstParty":false,"canonicalSlug":"halowerk-price-elasticity-estimator-0e998044"}