PluginPublic

testland/test-effort-estimation

Use when an epic or release is split into testable areas and someone must commit test capacity. Produces a PERT three-point estimate as ranges, with a named assumptions ledger and a split across developer, automation and exploratory work; also classifies a change set's shape from git history.

Quality

91%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide

Securityby

Passed

No findings from the security scan

Worked example - PERT arithmetic

Deep reference for the test-effort-estimation SKILL.md. The row-by-row PERT arithmetic behind the "Promo codes at checkout" epic, using the formulas from the spine (E = (a + 4m + b) / 6, SD = (b - a) / 6). The filled output document is in effort-estimate-output-template.md.

Epic: Promo codes at checkout (stories 12 to 15). Change-shape distribution supplied by the classifier: 30 percent service-layer, 25 percent ui-heavy, 25 percent pure-logic, 20 percent data-heavy. Three-point values gathered in a two-round Wideband Delphi with three estimators.

Row arithmetic:

Checkout flow (service):    E = (4 + 32 + 16)/6 = 8.7    SD = (16 - 4)/6 = 2.0
Checkout flow (UI/E2E):     E = (2 + 20 + 10)/6 = 5.3    SD = (10 - 2)/6 = 1.3
Discount-code API (service):E = (2 + 16 +  8)/6 = 4.3    SD = ( 8 - 2)/6 = 1.0
Discount rules (unit):      E = (3 + 20 +  9)/6 = 5.3    SD = ( 9 - 3)/6 = 1.0
Promo schema (data checks): E = (2 + 24 + 14)/6 = 6.7    SD = (14 - 2)/6 = 2.0
Checkout (exploratory):     E = (2 + 12 +  6)/6 = 3.3    SD = ( 6 - 2)/6 = 0.7

Aggregation:

E_total  = 8.7 + 5.3 + 4.3 + 5.3 + 6.7 + 3.3 = 33.6 h
SD_total = sqrt(2.0^2 + 1.3^2 + 1.0^2 + 1.0^2 + 2.0^2 + 0.7^2)
         = sqrt(4.00 + 1.69 + 1.00 + 1.00 + 4.00 + 0.49)
         = sqrt(12.18) = 3.5 h
Independent-rows range:   30.1 to 37.1 h
Fully-correlated bound:   sum(SD) = 8.0  ->  25.6 to 41.6 h

The two ranges are reported together because assumption A2 (staging availability) is shared by four of the six rows, so the independence assumption behind SD_total is known to be imperfect (Brunel University, Network analysis: uncertain completion times).