---
id:
aliases: []
title: Statistical Modeling for Construction Estimating
tags:
  - authorship/original
  - destiny/permanent
  - status/incomplete
  - topic/construction
  - topic/estimating
  - topic/math/statistics
  - type/cross-topic
---
# Statistical Modeling for Construction Estimating

Cross-topic of [[statistical-modeling]] and [[construction-estimating]].

## Bayesian Takeoff

#### User Story

Frank is estimating a 20-story high rise
and notices that their are roughly, but not exactly,
the same number of receptacles in the corridors of levels 2 to 19.
Frank starts a new takeoff for duplex receptacles,
typical of levels 2 to 19.
He counts and inputs quantities for 3 levels,
each adjusts the prior to calculate the expected quantity for all 18 levels.

## Stochastic Branch Takeoff

generate a BOM from point loads distributed in a space.

```yaml
- x: 302.84
  y: 2364.47
  kW: 5.3
  voltage: 277
  phases: 1
...
```

determine relative impact of factors
* allowable voltage drop

## Methods

> [!cite] Reddit u/mightofmerchants
> ![[spatial-sampling.gif|300x300]]

* Poisson disc sampling
* Delunay triangulation
* Voronoi diagrams

%% TODO: link paper on procedural generation of single family homes %%

## Average Distance Given Area

Holding area constant,
average taxicab distance between points
varies greatly with the aspect ratio of the space.
Weighted by a probability distribution
an average length and confidence could be given for any known area.

[[sigmoid-functions]]

Maximum area per floor is sometimes capped by
[[ibc-construction-types]] or [[ibc-occupancy-classifications]],
either directly (see [[ibc_ch05]], [[ibc_ch09]]),
or by maximum travel distance (see [[ibc_ch10]]).
Stairwells are expensive. There are usually only 2 or 3.