ASTM E3372-23

Standard Guide for Schedule Performance Index, Schedule Beta (β<inf>s</inf >)

SIGNIFICANCE AND USE
5.1 The schedule beta (βs) approach produces informational elements: Overall (or composite) schedule beta (βs), schedule beta upside (βs+), and schedule beta downside (βs–)—representing the quantitative components, and the qualitative insight (“early warning”) into the propensity for directional schedule performance for individual schedule participants.  
5.1.1 The quantitative component of schedule beta (βs) (inclusive of the upside and downside subvariants) is an index value that depicts schedule participant’s magnitude and direction of movement as compared to the overall project at an assigned value of 1.0, for example, a βs = +2.5 connotes performance of a schedule participant that moves in the same direction as the collection of completed projects at a rate of 2.5 units (schedule days) for each single unit (schedule day) experienced at the overall project level.  
5.1.2 The qualitative component of schedule beta (βs) (inclusive of the upside and downside subvariants) provides insight as a cautionary and predictive signal depicting the ability for an individual schedule participant to perform in-keeping with the initially-established as-planned schedule duration(s).  
5.2 Schedule beta (βs) also depicts the overall status or health (performing well or not) of a market sector, location and/or trade. Consistent larger schedule beta (βs) values are indicative of external elements (risks) impacting all participants sharing common attribute(s) (that is, trade, location, market sector, etc.).  
5.3 Schedule beta (βs) measures current schedule participant performance. As a rolling value (for example, calculated for projects completed during the two most recently completed full calendar years), it depicts the schedule performance ability of the schedule participant. See Note 1.
Note 1: Schedule Data Source and Usage—Schedule beta (βs) (inclusive of the upside and downside subvariants) utilizes schedule data from any schedule calculation method that depicts individ...
SCOPE
1.1 This guide covers schedule beta (βs), which measures construction project participant schedule performance versus that of the overall completed project and is based on beta (β) from financial portfolio theory for measuring the correlation between individual stock performance and that of the overall stock market.2 By correlating the delta of actual activity performance (“as-built”) minus that originally scheduled (“as-planned”) to the delta of as-built minus as-planned for the overall completed project for a participant’s collection of projects over a specified period of time, a schedule performance index is established in a similar manner as the aforementioned beta (β) of an individual stock.  
1.2 Schedule beta (βs) measures, as a unitless index value, schedule participant (“subcontractor’s”) performance—ahead or behind—as-planned duration as correlated to its respective overall project’s schedule performance.  
1.3 Schedule beta (βs) is measured with input from at least two (2) independent (mutually exclusive) projects that have reached completion, within the defined period of observation.  
1.4 Schedule beta (βs) is measured across a standard predetermined period of time, in similar fashion to that of the insurance industry’s experience modification rate’s (EMR) most recent two (2) complete calendar years within the past thirty-six (36) months.  
1.5 Schedule beta (βs) evaluates schedule participant’s (“subcontractor’s”) most recent performance, not its complete history, such that is it indicative of current performance and contemporary influences—market, geographic, industry trade, etc.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This internation...

General Information

• Status: Published
• Publication Date: 31-Jan-2023
• ICS: 03.060 - Finances. Banking. Monetary systems. Insurance
• Technical Committee: E06 - Performance of Buildings
• Drafting Committee: E06.81 - Building Economics

Relations

• Refers: ASTM E2691-20 - Standard Practice for Job Productivity Measurement
• Effective Date: 01-Apr-2020
• Refers: ASTM E2691-16 - Standard Practice for Job Productivity Measurement
• Effective Date: 01-Mar-2016
• Refers: ASTM E2587-15 - Standard Practice for Use of Control Charts in Statistical Process Control
• Effective Date: 01-Apr-2015
• Refers: ASTM E631-15 - Standard Terminology of Building Constructions
• Effective Date: 01-Mar-2015
• Refers: ASTM E631-14 - Standard Terminology of Building Constructions
• Effective Date: 01-Nov-2014
• Refers: ASTM E2587-14e1 - Standard Practice for Use of Control Charts in Statistical Process Control
• Effective Date: 01-Oct-2014
• Refers: ASTM E2587-14 - Standard Practice for Use of Control Charts in Statistical Process Control
• Effective Date: 01-Oct-2014
• Refers: ASTM E833-13b - Standard Terminology of Building Economics
• Effective Date: 01-Nov-2013
• Refers: ASTM E833-13a - Standard Terminology of Building Economics
• Effective Date: 15-Oct-2013
• Refers: ASTM E833-13 - Standard Terminology of Building Economics
• Effective Date: 01-Oct-2013
• Refers: ASTM E2587-12 - Standard Practice for Use of Control Charts in Statistical Process Control
• Effective Date: 01-Dec-2012
• Refers: ASTM E833-12 - Standard Terminology of Building Economics
• Effective Date: 01-May-2012
• Refers: ASTM E2166-12 - Standard Practice for Organizing and Managing Building Data
• Effective Date: 01-Apr-2012
• Refers: ASTM E1946-12 - Standard Practice for Measuring Cost Risk of Buildings and Building Systems and Other Constructed Projects
• Effective Date: 01-Apr-2012
• Refers: ASTM E2691-11 - Standard Practice for Job Productivity Measurement
• Effective Date: 01-Nov-2011

Overview

ASTM E3372-23: Standard Guide for Schedule Performance Index, Schedule Beta (βs), provides guidance on measuring construction schedule performance for project participants in comparison to the overall project. Schedule Beta (βs), adapted from financial portfolio theory, is a unitless index that correlates the performance of individual project participants (such as subcontractors) to the project's overall schedule performance. This approach delivers both quantitative results - indicating the magnitude and direction of schedule deviation - and qualitative insights, offering early warning of schedule trends and possible risks. The standard is ideally suited for construction professionals seeking objective, repeatable performance measurement methods.

Key Topics

• Schedule Beta (βs) Index: The core concept is the calculation of a unitless index that expresses each participant’s schedule performance (whether ahead of or behind as-planned durations) relative to the overall project baseline.
• Quantitative & Qualitative Guidance: βs offers not just numerical performance measures (including upside and downside subvariants) but also actionable, “early warning” information for decision-making and risk management.
• Rolling, Contemporary Evaluation: The standard ensures βs remains a current performance metric by requiring evaluation across a recent, fixed period (such as the last two completed calendar years), similar to experience modification rates in insurance.
• Data Requirements and Validity: Reliable computation of schedule beta relies on accurate, complete, and regularly updated as-planned and as-built schedule data from at least two mutually exclusive, completed projects.
• Schedule Performance as Management Tool: Results from the βs calculation can be benchmarked, trended, and compared across market sectors, locations, trades, or contractors to understand systemic issues or unique participant performance.
• Subvariants - Upside and Downside:
  • Schedule beta upside (βs+) measures ahead-of-schedule performance.
  • Schedule beta downside (βs–) quantifies delays relative to plan.

Applications

• Contractor and Trade Evaluation: Use βs to objectively assess the schedule performance of subcontractors or specialty trades during prequalification, selection, or bid evaluation processes.
• Project Team Formation: Owners and general contractors can assemble teams with a history of reliable schedule adherence, mitigating risk in fast-track projects or those with stringent deadlines.
• Performance Trending & Risk Assessment: Monitor trends over multiple schedule periods to identify systemic problems, external risk influences (such as market or geographic disruptions), or improvements in schedule management practices.
• Benchmarking for Continuous Improvement: Compare βs among organizations, sectors, or locations to advance industry-wide understanding and foster collaborative improvement.
• Data-Driven Reporting: Develop standardized, comparable reports for management, owners, and external agencies, enabling informed decisions based on current, factual schedule performance indices.

Related Standards

ASTM E3372-23 references and is complemented by several key ASTM standards:

• ASTM E631 - Terminology of Building Constructions
• ASTM E833 - Terminology of Building Economics
• ASTM E1946 - Practice for Measuring Cost Risk of Buildings and Building Systems
• ASTM E2166 - Practice for Organizing and Managing Building Data
• ASTM E2587 - Practice for Use of Control Charts in Statistical Process Control
• ASTM E2691 - Practice for Job Productivity Measurement

These related standards support the comprehensive evaluation of construction project performance, risk, and productivity, optimizing the value delivered through use of schedule performance indices like Schedule Beta (βs).

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Keywords: ASTM E3372-23, Schedule Performance Index, Schedule Beta, construction scheduling, as-planned vs as-built, project schedule performance, construction benchmarking, schedule risk management, subcontractor evaluation, engineering standard.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E3372 − 23
Standard Guide for
Schedule Performance Index, Schedule Beta (β )
s
This standard is issued under the fixed designation E3372; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The schedule performance index, schedule beta (β ), correlates the performance of network
s
schedule participants (critical path method (CPM)) at the activity level to the overall project
performance on an ongoing basis. The value of the index is representative of the collection of
completed activities within their respective projects over a defined period of time. It identifies the
propensity of schedule participants to fulfill their initial schedule durations (“as-planned”) by
delivering their work on-time, which may be used as an indicator of future performance. Schedule beta
(β ) enables contractors, project managers, supervisors, and schedulers to include indicative
s
performance when assembling construction project teams, evaluate potential participant appropriate-
ness considering schedule time constraints, and improve schedule accuracy and performance.
1. Scope 1.4 Schedule beta (β ) is measured across a standard prede-
s
termined period of time, in similar fashion to that of the
1.1 This guide covers schedule beta (β ), which measures
s
insurance industry’s experience modification rate’s (EMR)
construction project participant schedule performance versus
most recent two (2) complete calendar years within the past
that of the overall completed project and is based on beta (β)
thirty-six (36) months.
from financial portfolio theory for measuring the correlation
between individual stock performance and that of the overall 1.5 Schedule beta (β ) evaluates schedule participant’s
s
stock market. By correlating the delta of actual activity (“subcontractor’s”) most recent performance, not its complete
performance (“as-built”) minus that originally scheduled (“as- history, such that is it indicative of current performance and
planned”) to the delta of as-built minus as-planned for the contemporary influences—market, geographic, industry trade,
overall completed project for a participant’s collection of etc.
projects over a specified period of time, a schedule perfor-
1.6 This standard does not purport to address all of the
mance index is established in a similar manner as the afore-
safety concerns, if any, associated with its use. It is the
mentioned beta (β) of an individual stock.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
1.2 Schedule beta (β ) measures, as a unitless index value,
s
mine the applicability of regulatory limitations prior to use.
schedule participant (“subcontractor’s”) performance—ahead
1.7 This international standard was developed in accor-
or behind—as-planned duration as correlated to its respective
dance with internationally recognized principles on standard-
overall project’s schedule performance.
ization established in the Decision on Principles for the
1.3 Schedule beta (β ) is measured with input from at least
s
Development of International Standards, Guides and Recom-
two (2) independent (mutually exclusive) projects that have
mendations issued by the World Trade Organization Technical
reached completion, within the defined period of observation.
Barriers to Trade (TBT) Committee.
1 2. Referenced Documents
This guide is under the jurisdiction of ASTM Committee E06 on Performance
of Buildings and is the direct responsibility of Subcommittee E06.81 on Building 3
2.1 ASTM Standards:
Economics.
E631 Terminology of Building Constructions
Current edition approved Feb. 1, 2023. Published June 2023. DOI: 10.1520/
E3372-23. E833 Terminology of Building Economics
The schedule performance index, schedule Beta (β ), is based on the Beta (β)
s
factor as found in the Capital Asset Pricing Model (CAPM) of financial portfolio
theory, as formalized by Black, Jensen, and Scholes in Jensen, M. C., Black, F.,
Scholes, M. S., “The Capital Asset Pricing Model: Some Empirical Tests.” In For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Studies in the Theory of Capital Markets, ed. M. C. Jensen, Praeger Publishers, Inc., contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
New York, NY, 1972, which received the 1990 Alfred Nobel Memorial Prize in Standards volume information, refer to the standard’s Document Summary page on
financial economics (Sharpe and Markowitz and Miller). the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E3372 − 23
E1946 Practice for Measuring Cost Risk of Buildings and
m = index of market performance,
¯
Building Systems and Other Constructed Projects
R = the asset prior performance
i
E2166 Practice for Organizing and Managing Building Data
benchmark, commonly the previous
E2587 Practice for Use of Control Charts in Statistical
day’s individual stock return, and
¯
Process Control
R = the market prior performance
m
E2691 Practice for Job Productivity Measurement benchmark, commonly the previous
day’s overall market return.
3. Terminology
3.3.3.1 Discussion—See CAPM definition for R and R .
i m
3.1 Definitions (General)—For general definitions of terms
used in this guide, refer to Terminology E631 and Terminology
3.3.4 capital asset pricing model (CAPM) —the Capital
E833.
Asset Pricing Model (CAPM), as developed by Black, Jensen,
3.2 Definitions (Companion Standard Practices)—For defi- and Scholes, and represented by the following formula:
nitions of terms used in this guide relative to cost risk, refer to
E R 5 r 1β · E R 2 r
~ ! @ ~ ! #
i f i m f
Practice E1946. For definitions of terms used in this guide
where:
relative to building data, refer to Practice E2166. For defini-
tions of terms used in this guide relative to statistical process E(R ) = the expected return of a capital asset (an
i
control and control charts, refer to Practice E2587. For
individual stock),
definitions of terms used in this guide relative to job produc- E(R ) = the expected return of the overall market,
m
E(R ) – r = known as the “market premium” or the “risk
tivity measurement, refer to Practice E2691.
m f
premium,” is the difference between the ex-
3.3 Definitions of Terms Specific to This Standard:
pected market rate of return and the risk-free
3.3.1 as-built duration—the resulting time an individual
rate of return,
activity or the overall construction project actually expended to
r = the risk-free rate of return, such as interest
f
complete the work.
arising form government bonds,
3.3.1.1 Discussion— Individual activity as-built durations
R = the return of an individual capital asset, typi-
i
may be longer or shorter than the as-planned duration. The
cally that of an individual company’s stock,
overall project as-built duration is the sum of the critical
R = the return of the overall market, and
m
activities (those comprising the critical path) forming the
β = beta is the sensitivity of the expected excess
i
longest uninterrupted sequence of activities in the overall
asset returns to the expected excess market
schedule as actually expended. The critical path resulting in the
returns; see financial beta and beta (β) defini-
completed project may not be comprised of the same critical
tion for mathematical expression.
activities as initially established in the as-planned schedule due
3.3.5 covariance—mathematically defined as the arithmetic
to extensions and/or contractions in actual time expended to
mean of the products of the deviations of the corresponding
complete the work of individual schedule activities.
values of two quantitative variables from their respective
3.3.2 as-planned duration—the amount of time initially
arithmetic means.
established for an individual activity or the overall construction
3.3.5.1 Discussion—Specific to the schedule beta (β )
project to be completed.
s
calculation, covariance is defined as the arithmetic mean of the
3.3.2.1 Discussion—Individual activity as-planned dura-
tions are discrete values assumed independent from other product of the deviation of schedule participant activity per-
activities within the same construction project. The overall formance from as-planned to as-built (the “activity duration
project as-planned duration is the sum of the critical activities
delta”) to its mean value and the mean of the product of the
(those comprising the critical path) forming the longest unin-
deviation of the overall project schedule performance from
terrupted sequence of activities in the overall schedule as
as-planned to as-built (the “project duration delta”) to its mean
initially established.
value.
3.3.3 financial beta —the mathematical coefficient as found
3.3.6 critical chain—critical chain is a schedule network
in the CAPM that describes the historic movement of an
analysis technique that modifies the project schedule to account
individual security’s (an individual stock’s) daily returns to the
for limited resources.
corresponding daily return of the entire market, as defined by
3.3.6.1 Discussion—Initially, the project schedule network
the formula:
diagram is built using duration estimates with required depen-
Beta β 5 Covariance R , R ⁄ Variance R
~ ! ~ ! ~ !
i m m
dencies and defined constraints as inputs. The critical path is
where: then calculated. After the critical path is identified, resource
¯ ¯ availability is entered and the resource-limited schedule result
Covariance (R , R ) = [(R – R ) · (R – R )],
i m i i m m
¯
Variance (R ) = (R – R ) ,
m i i
i = index of individual asset
performance,
The Capital Asset Pricing Model (CAPM) of financial portfolio theory has been
formalized by Black, Jensen, and Scholes (1972).
Covariance definition from Merriam-Webster website, www.merriam-
Beta (β) has been formalized by Black, Jensen, and Scholes (1972). webster.com.
E3372 − 23
is determined. The resulting schedule often has an altered
d = the as-built duration of an individual
j
critical path. The resource-constrained critical path is known as
schedule participant activity within
the critical chain.
its respective construction project
completed during the specified pe-
3.3.7 critical path method (CPM)—the critical path method
riod of time, herein defined as the
calculates the theoretical early start and finish dates, and late
resulting actual activity duration as
start and finish dates, for all activities without regard for any
presented in the final published ver-
resource limitations, by performing a forward and backward
sion of the construction project
pass analysis through the schedule network.
schedule,
3.3.8 earned value management (EVM)—earned value man-
d = the as-planned duration performance
i
agement (EVM) in its various forms is a commonly used
benchmark of an individual schedule
method of performance measurement.
participant activity within an indi-
3.3.8.1 Discussion— It integrates project scope, cost, and
vidual construction project com-
schedule measures to help the project management team assess
pleted during the specified period of
and measure project performance and progress. It is a project
time, herein defined as the activity
management technique that requires the formation of an
schedule duration as presented in the
integrated baseline against which performance can be mea-
initial published version of the con-
sured for the duration of the project. The principles of EVM
struction project schedule,
can be applied to all projects, in any industry. EVM develops
¯
d = the statistical mean benchmark value
i
and monitors three key dimensions for each work package and
of the delta of the as-built durations
control account: planned value (PV), earned value (EV), actual
minus the as-planned durations of
cost (AC).
the schedule participant activities for
3.3.9 schedule beta (β )—the mathematical coefficient (in-
s the projects completed during the
dex value) rooted in the CAPM and extended to network
specified period of time,
schedule systems to describe the historic movement of an
D = the deltas of the as-planned durations
m
individual schedule participant’s (an individual subcontrac-
minus the as-built durations of the
tor’s) deviation from as-planned to as-built schedule perfor-
overall construction projects com-
mance versus that of the overall project’s deviation from
pleted during the specified period of
as-planned to as-built schedule performance over a specified
time,
period of time, as defined by the formula:
d = the as-built duration of the overall
n
construction project completed dur-
Schedule Beta ~β! 5 Covariance~D , D ! ⁄ Variance~D !
i m m
ing the specified period of time,
where:
herein defined as the project duration
¯ ¯
Covariance (D , D ) = [(d – d ) · (d – d ),
as presented in the final published
i m j i n m
¯
Variance (D ) = (d – d ) ,
m n m version of the construction project
¯ ¯ ¯
β = ∑(d – d ) · (d – d ) / ∑(d – d ) ,
s j i n m n m
schedule,
i = the index for labeling as-planned
d = the as-planned duration of the overall
m
activities,
construction project completed dur-
j = the index for labeling as-built
ing the specified period of time,
activities,
herein defined as the project duration
m = the index for labeling as-planned
as presented in the initial published
projects,
version of the construction project
n = the index for labeling as-built
schedule, and
projects,
¯
d = the statistical mean benchmark value
m
D = the delta of the as-built durations to
i
of the delta of the as-built durations
the as-planned durations of the
minus the as-planned durations of
schedule participant activities for the
the overall corresponding individual
projects completed during the speci-
construction project for the projects
fied period of time,
completed during the specified pe-
riod of time, herein defined as the
values resulting from total project
Critical Chain definition from Section 6.5.2.3, Project Management Book of
Knowledge (PMBOK) 4th Edition, Project Management Institute (PMI) ANSI/PMI
schedule duration as presented in the
99–001–2008.
initial published version of the con-
Critical Path Method definition from Section 6.5.2.2, Project Management
struction project schedule.
Book of Knowledge (PMBOK) 4th Edition, Project Management Institute (PMI)
ANSI/PMI 99–001–2008.
3.3.10 schedule beta benchmark (β )—the collective
9 s-bm
Earned Value Management (EVM) definition from Section 7.3.2.1, Project
mathematical coefficient (index value) rooted in the CAPM and
Management Book of Knowledge (PMBOK) 4th Edition, Project Management
Institute (PMI) ANSI/PMI 99–001–2008. extended to network schedule systems to describe the historic
E3372 − 23
movement of an individual schedule participant’s (an indi- 4.1.4 Section 4, Summary of Guide—Outlines the contents
vidual subcontractor’s) deviation from as-planned to as-built of this guide.
schedule performance versus that of the overall project’s 4.1.5 Section 5, Significance and Use—Explains the signifi-
deviation from as-planned to as-built schedule performance cance and use of the array of schedule beta (β ) values.
s
irrespective of any specified period of time—inclusive of the 4.1.6 Section 6, Procedure—Lists the steps for calculating
entire population of projects. the array of schedule beta (β ) values.
s
4.1.7 Section 7, Data Sources and Assumptions—Describes
3.3.11 schedule beta upside (β )—the mathematical coef-
s+
the raw data required, their format, and use in the calculation
ficient (index value) rooted in the CAPM and extended to
of the array of schedule beta (βs) values.
network schedule systems to describe the historic movement of
4.1.8 Section 8, Calculation of the Schedule Performance
an individual schedule participant’s (an individual subcontrac-
Index, Schedule Beta (β )—Depicts the calculation of the array
s
tor’s) deviation from as-planned to as-built schedule perfor-
of schedule beta values—schedule beta (β ), schedule beta
s
mance versus that of the overall project’s deviation from
upside (β ), and schedule beta downside (β ), using data
s+ s–
as-planned to as-built schedule performance when limited to
gathered according to Section 7 and with output defined by
performance on construction projects for which the as-built
Section 10.
schedule duration is less than the as-planned schedule dura-
4.1.9 Section 9, Applications—Describes where and how
tion. That is, the construction project finished ahead of the
schedule beta (β ) values can be used.
s
as-planned duration: The project took less time to finish than
4.1.10 Section 10, Report—Describes the various types of
originally established.
output and reports.
3.3.12 schedule beta downside (β )—the mathematical co-
s–
4.1.11 Section 11, Precision, Bias—Expected values for the
efficient (index value) rooted in the CAPM and extended to
array of schedule beta (β ) values. Reserved for future devel-
s
network schedule systems to describe the historic movement of
opment.
an individual schedule participant’s (an individual subcontrac-
4.1.12 Section 12, Keywords—Lists related words and
tor’s) deviation from as-planned to as-built schedule perfor-
phrases related to the schedule beta (β ) approach.
s
mance versus that of the overall project’s deviation from
as-planned to as-built schedule performance when limited to
5. Significance and Use
performance on construction projects for which the as-built
5.1 The schedule beta (β ) approach produces informational
s
schedule duration is greater than the as-planned schedule
elements: Overall (or composite) schedule beta (β ), schedule
s
duration. That is, the construction project finished behind the
beta upside (β ), and schedule beta downside (β )—
s+ s–
as-planned duration: The project took more time to finish than
representing the quantitative components, and the qualitative
originally established.
insight (“early warning”) into the propensity for directional
3.3.13 schedule participant—the specific owner of an activ-
schedule performance for individual schedule participants.
ity and/or collection of activities within a construction project
5.1.1 The quantitative component of schedule beta (β )
s
network schedule (critical path method, CPM) system, com-
(inclusive of the upside and downside subvariants) is an index
monly considered to be a subcontractor; schedule participants
value that depicts schedule participant’s magnitude and direc-
typically are responsible for (“own”) multiple schedule activi-
tion of movement as compared to the overall project at an
ties within the network schedule system.
assigned value of 1.0, for example, a β = +2.5 connotes
s
3.3.14 specified period of time—the time in calendar years
performance of a schedule participant that moves in the same
during which completed construction projects will be used to
direction as the collection of completed projects at a rate of 2.5
calculate schedule beta (β ) and its subvariants schedule beta
units (schedule days) for each single unit (schedule day)
s
upside and downside.
experienced at the overall project level.
5.1.2 The qualitative component of schedule beta (β ) (in-
3.3.15 variance—mathematically defined as the square of
s
clusive of the upside and downside subvariants) provides
the standard deviation; specific to the schedule beta (β )
s
insight as a cautionary and predictive signal depicting the
calculation, variance is defined as sum of the squares of the
ability for an individual schedule participant to perform in-
standard deviation of the array of overall project activity
keeping with the initially-established as-planned schedule
duration deltas.
duration(s).
4. Summary of Guide
5.2 Schedule beta (β ) also depicts the overall status or
s
4.1 This guide is organized as follows:
health (performing well or not) of a market sector, location
4.1.1 Section 1, Scope—Identifies the coverage of schedule and/or trade. Consistent larger schedule beta (β ) values are
s
beta (β ).
indicative of external elements (risks) impacting all partici-
s
4.1.2 Section 2, Referenced Documents—Lists ASTM stan- pants sharing common attribute(s) (that is, trade, location,
dards referenced in this guide.
market sector, etc.).
4.1.3 Section 3, Terminology—Addresses definitions of
5.3 Schedule beta (β ) measures current schedule participant
s
terms used in this guide.
performance. As a rolling value (for example, calculated for
projects completed during the two most recently completed full
calendar years), it depicts the schedule performance ability of
Variance definition from Merriam-Webster website, http://www.merriam-
webster.com. the schedule participant. See Note 1.
E3372 − 23
NOTE 1—Schedule Data Source and Usage—Schedule beta (β ) (inclu-
network schedule system (CPM schedule) into numeric values
s
sive of the upside and downside subvariants) utilizes schedule data from
for direct input and itemization of the relevant elements for
any schedule calculation method that depicts individual activity duration
schedule participant-s
...