Glossary

The following terms are used throughout Open Plan documentation.

A

Field	Description
Access Rights	The rights that a user may have to a file. Open Plan recognizes the following types of rights: Read Only: The user may read and copy the file, but may not edit or delete it. Write: The user may make any desired changes to the file. Owner: The user may make any desired changes to the file and may also define the rights other users may have to the file.
Activity	The smallest self-contained unit of work used to define the logic of a project. In general, activities share the following characteristics: They have a definite duration. They may have logical relationships to other activities in a project. They use resources such as people, materials, or facilities. They have an associated cost.
Activity File	The data tables corresponding to the ACT file in other versions of Open Plan.
Activity ID	A unique code identifying each activity in a project.
Activity Status	The state of completion of an activity: Planned: The activity has not yet started. In Progress: The activity is in progress. Complete: The activity is complete.
Actual Cost of Work Performed (ACWP)	Actual cost expended on an activity, a part of a project, or an entire project.
Actual Cost to Date	See Actual Cost of Work Performed.
Actual Finish	Date on which an activity was completed.
Actual Start	Date on which an activity was started.
ACWP (Actual Cost of Work Performed)	Actual cost expended on an activity, a part of a project, or an entire project.
ALAP (As Late As Possible)	An activity for which Open Plan sets the early dates to be as late as possible without delaying the early dates of any successor.
Alternate Resource	A resource that Open Plan may substitute for an activity requirement during resource scheduling if the requested resource is not available. An alternate resource may be an individual, a pool, or a skill.
Ancillary File	Another name is Auxiliary File. A file that is assigned to a project. Open Plan uses three types of ancillary files: Resource Files: A project may have only one assigned resource file. The resource file, however, may contain any number of resources. Calendar Files: A project must have a calendar file. The calendar file, however, may contain any number of calendars. Code Files: A project and/or a resource file may have up to 90 assigned code files. Each code file may contain any number of codes.
As-Late-As-Possible (ALAP)	An activity for which Open Plan sets the early dates to be as late as possible without delaying the early dates of any successor.
As-Soon-As-Possible (ASAP)	An activity for which Open Plan sets the early dates to be as soon as possible. This is the default activity type.
ASAP (As-Soon-As-Possible)	An activity for which Open Plan sets the early dates to be as soon as possible. This is the default activity type.
Assignment Profile Curve	A profile that describes how a resource assignment is spread through the duration of an activity. Open Plan provides seven standard assignment profile curves: back load, double peak, early peak, front load, late peak, linear, and normal (bell).
Asymmetrical Distribution	A probability distribution not symmetrical about its central tendency. Same as skewed distribution.
Auxiliary File	Another name is Ancillary File. A file that is assigned to a project. Open Plan uses three types of ancillary files: Resource Files: A project may have only one assigned resource file. The resource file, however, may contain any number of resources. Calendar Files: A project must have a calendar file. The calendar file, however, may contain any number of calendars. Code Files: A project and/or a resource file may have up to 90 assigned code files. Each code file may contain any number of codes.
Availability Threshold	In resource-limited scheduling, it is possible to specify that a particular resource may be exceeded, if necessary, by an amount not to exceed the specified threshold for that resource.
Average	A measure of central tendency of a sample or a probability distribution, obtained by adding the individual values in a sample and dividing by the sample size. Same as mean or expected value.

B

Field	Description
BAC (Budget at Completion)	The total budget for a project or part of the project. When the project is complete, both the BCWS and the BCWP are equal to the BAC.
Backward Pass	A procedure within time analysis to calculate the late start and late finish dates of all activities in a project.
Barchart View	A project view that uses horizontal bars on a time scale to depict activity information. In Open Plan, a barchart view is a composite view that can display an activity barchart, a spreadsheet, and, if resources are assigned to the project, a histogram. A barchart is frequently called a Gantt chart.
Baseline	A copy of the project schedule at a particular time that is used for comparison with the current schedule.
Baseline Dates	Original planned start and finish dates for an activity.
BCWP (Budgeted Cost of Work Performed)	A measure used in cost control that allows you to quantify the overall progress of the project in monetary terms. BCWP is calculated by multiplying the physical percent complete by the planned cost. Another term for BCWP is "earned value." Comparison with ACWP indicates how far the project is above or below budget.
BCWS (Budgeted Cost of Work Scheduled)	Planned cost multiplied by the percentage of completion that should have been achieved according to the project baseline dates. Comparison with BCWP gives a monetary measure of how far the project is ahead of or behind schedule.
Beta Distribution	A family of continuous probability distributions in which the random variable varies in the range of 0 to 1 and with a skew and kurtosis ("peakedness") that depends on a pair of parameters. In the context of Open Plan, the definition of the beta distribution has been expanded to allow random variables distributed between any pair of user-specified values, instead of always between 0 and 1.
Breakdown Structure	A hierarchical structure for codes that allows you to summarize project data for reporting.
Budget	Planned cost for an activity or project.
Budget at Completion (BAC)	The total budget for a project or part of the project. When the project is complete, both the BCWS and the BCWP are equal to the BAC.
Budgeted Cost of Work Performed (BCWP)	A measure used in cost control that allows you to quantify the overall progress of the project in monetary terms. BCWP is calculated by multiplying the physical percent complete by the planned cost. Another term for BCWP is "earned value." Comparison with ACWP indicates how far the project is above or below budget.
Budgeted Cost of Work Scheduled (BCWS)	Planned cost multiplied by the percentage of completion that should have been achieved according to the project baseline dates. Comparison with BCWP gives a monetary measure of how far the project is ahead of or behind schedule.

C

Field	Description
Calendar	A definition of valid working periods for a group of project activities or resources.
Calendar File	A file containing calendar information for one or more calendars.
Central Tendency	The central area of a probability distribution, usually corresponding to the mode ("most likely") or mean ("average") value of the random variable. Most of the results of Open Plan processing use the mean to measure central tendency.
Child	A lower-level element in a hierarchical structure.
Code File	A file used in reporting that contains information associated with codes entered on an activity record or a resource record.
Compound Activity	A group of activities represented as a single activity in a higher level of the same project.
Confidence	The likelihood of a statistical deduction from empirical data. Confidence is usually expressed as a percentage and applied to a range of possibilities.
Confidence Interval	A pair of values bracketing an estimate (usually derived from sampled data), indicating that there is some stated percentage probability that the true value falls within that range. It is generally implicit that the interval is symmetrical, in the sense that there is an equal probability of the true value being outside the interval in either direction. For example, a 99% confidence interval would be a pair of values such that there is a 0.5% chance of the true value being less than the lower value and a 0.5% chance that the true value is greater than the higher value.
Constraint	Date imposed on an activity or project by the user. There are two types of target dates: target start dates and target finish dates.
Consumable Resource	A type of resource that remains available until consumed (for example, a material).
Controlling Critical Activity	An activity that has float due to its own calendar but that causes a successor to be critical.
Controlling Relationship	A relationship that controls the early date of the successor activity. In Open Plan, a controlling relationship can be detected by its free float being zero.
Cost Escalation	The feature that allows you to specify different resource unit costs and the date on which each new cost takes effect.
Cost Variance (CV)	The difference between the earned value and the actual cost of work performed. (BCWP – ACWP).
Critical Activity	An activity is termed critical when it has zero or negative float.
Critical Path	Series of consecutive activities that represent the longest path through the project.
Criticality Index	Used in risk analysis, the criticality index represents the percentage of simulation trials that resulted in the activity being placed on the critical path.
Cumulative Distribution	The representation of a probability distribution as a cumulative curve. Each point on the curve represents the probability that the random variable will be no greater than the value represented by that point. By definition, the height of such a curve must be non-decreasing, starting at zero and increasing to one.

D

Field	Description
Default Calendar	If no user-created calendar file is associated with the project, the default calendar is used for date calculations. The default calendar is defined as Monday through Friday, 8 A.M. to 4 P.M., and no holidays.
Delaying Resource	In resource scheduling, inadequate availability of one or more resources may require that the completion of an activity be delayed beyond the date on which it could otherwise be completed. The delaying resource is the first resource on an activity that causes the activity to be delayed.
Dependency	A logical connection between two activities.
Discontinuous Activity	An activity in which the interval between the start and finish dates is allowed to exceed its duration in order to satisfy start-to-start and finish-to-finish relationships with other activities.
Distribution	The representation of the range and relative probabilities of the possible outcomes from a random process. A probability distribution may be in the form of a table, a curve, or a histogram.
Duration	The number of working periods required to perform the work represented by an activity. In risk analysis, this can correspond to the "most likely" duration.

E

Field	Description
Earliest Feasible Date	The earliest date on which the activity could be scheduled to start based on the scheduled dates of all its predecessors but in the absence of any resource constraints on the activity itself. This date is calculated by resource scheduling.
Early Dates	Calculated in the forward pass of time analysis. Early dates are the earliest dates on which an activity can start and finish.
Early Finish	The earliest date on which an activity can finish. This date is calculated by time analysis.
Early Start	The earliest date on which an activity can start. This date is calculated by time analysis.
Earned Value Cost Control	A cost control that allows you to quantify the overall progress of the project in monetary terms. Earned value is calculated by multiplying the physical percent complete by the planned cost. Another term for earned value is budgeted cost of work performed (BCWP).
Effort Driven	Open Plan calculates the duration of this activity based on the resource assignment and the effort factor defined for the resource. If more than one resource is assigned to the activity, Open Plan calculates the potential duration using the effort factor of each resource. Open Plan then uses the longest calculated duration for the activity. If you change an activity type to Effort Driven, Open Plan displays a message alerting you to the effects of this change.
End Activity	An activity (for example, A) is treated as an end activity if it meets all of the following conditions: It has no logical successors. Its parent is an end activity. None of its descendants has a successor that is not also a descendant of A. An end activity is also known as a finish activity.
Escalation	A feature that allows you to specify different resource unit costs and the date on which each new cost takes effect.
Exclusive Mode	If you have the file open in exclusive mode, other users can only have read-only access to the file while you are using it. While you can make any changes to the file that you want, Open Plan does not save these changes until you save the file.
External Subproject	A complete project represented as a single activity in a higher-level project. Open Plan uses external subprojects for multi-project processing.
Extra Work Day	An exception to the standard non-working day. For example, assume that a calendar defines Monday through Friday as days on which work is normally performed. In this case, a specific Saturday might be identified as an extra work day if work is to be performed on that day.

F

Field	Description
Finish Activity	An activity that has no successor. Also known as an end activity.
Finish Float	The number of work periods between the early finish date and the late finish date.
Finish Milestone	A milestone activity signifying the end of a project phase. If the activity duration is zero, Open Plan replaces the early and late start dates with the early and late finish dates during time analysis. Define zero-duration activities as either start or finish milestones if you want to avoid showing an activity that is scheduled to finish before it starts.
Finish-to-Finish Relationship	The relationship between activities that specifies that the finish of the successor activity depends on the completion of the predecessor activity. In most cases, this means that the successor activity cannot be completed before the predecessor activity is completed.
Finish-to-Start Relationship	The relationship between activities that specifies that the start of the successor activity depends on the completion of the predecessor activity. In most cases, this means that the successor activity cannot start until the predecessor activity is completed. This is the default relationship.
Fixed-Form Significant Coding Structure	A coding structure that relies on the length of the code to represent the structure level.
Float	The number of time periods by which an activity can be delayed without affecting other activities in a project. See also Free Float and Total Float.
Flowchart	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Foreign Activity	A placeholder activity that represents an activity in a different project that has a relationship to an activity in the currently open project.
Foreign Project	Open Plan creates a foreign project in order to contain any foreign activities that belong to a project that is not an external subproject of the current project.
Foreign Subproject	An internal subproject of a foreign project. If a foreign activity is not at the top of the hierarchy in its project, Open Plan validates the structure by creating a foreign subproject.
Forward Pass	A procedure within time analysis to determine the early start and early finish dates of activities.
Free Float	The maximum amount by which an activity can be delayed beyond its early dates without delaying any successor activity beyond its early dates. In the absence of finish targets, free float is always less than or equal to total float.
Free Slack	The maximum amount by which an activity can be delayed beyond its early dates without delaying any successor activity beyond its early dates. In the absence of finish targets, free float is always less than or equal to total float.

G

Field	Description
Gantt (Barchart View)	A project view that uses horizontal bars on a time scale to depict activity information. In Open Plan, a barchart view is a composite view that can display an activity barchart, a spreadsheet, and, if resources are assigned to the project, a histogram. A barchart is frequently called a Gantt chart.
Group	A block of data in a spreadsheet that begins with a subheading and ends with a subtotal.

H

Field	Description
Hammock	An activity that plays no part in time analysis but which provides the means to report on the start and finish of a group of activities.
Hard Zeros	In resource scheduling, there is a distinction made between resource availabilities specified as zero but which can be exceeded under certain circumstances and hard zeros, which can never be exceeded.
Hierarchical Coding Structure	A coding system that can be represented as a multi-level tree structure in which every code except those at the top of the tree has a parent code.
Hierarchical Project	A project that allows you to break down project information into multiple levels using the activity ID. With hierarchical projects, you enter project data at the lowest level of the project hierarchy, then summarize it to appropriate levels for reporting purposes.
Hierarchical Resource Structure	Resource definitions organized in a hierarchical structure in which every resource except those at the top of the tree has a parent.
Histogram View	A view in which data is shown as vertical bars, S-curves, or tables against a time scale. In Open Plan, two types of histograms are available: resource histograms and risk analysis histograms.
Holiday	An exception to the standard working day. For example, assume that a calendar defines Monday through Friday as days on which work is normally performed. In this case, a specific Monday (such as the Monday observed as Memorial Day) might be identified as a holiday if the office would be closed on that day.

I

Field	Description
Immediate Activity	An activity that can be forced to start on its earliest feasible date by resource scheduling, even if that means overloading a resource.
In Progress	An activity partially completed.
Internal Subproject	A group of activities represented as a single activity in a higher level of the same project.
Iteration	In Open Plan, one complete trial of Monte Carlo simulation of a project (that is, sampling a value for each activity duration, performing a time analysis with this sampled data, and storing the results). The Monte Carlo technique accumulates the results from a large number of these iterations.

K

Field	Description
Key Activity	In Open Plan, an activity specified by a user about which the program is to store detailed information generated by risk analysis.
Kurtosis	A technical term used to define a characteristic of the shape of a probability distribution, identified with the thickness of the tails of the distribution.

L

Field	Description
Labor Resources	Open Plan permits certain resources to be flagged as representing labor. The significance of this is that only resources so flagged will be included in the labor percent complete calculations.
Ladder	A style for displaying children in a breakdown structure.
Lag	A time delay associated with a relationship in a project. Lag can be either positive or negative. Negative lag is sometimes called "lead."
Late Dates	Calculated in the backward pass of time analysis. Late dates are the latest dates on which an activity can start and finish.
Late Finish	The latest date on which an activity must be completed if the project completion date and any finish targets are to be met. This date is calculated by time analysis.
Late Start	The latest date on which an activity must start if the project completion date and finish targets are to be met. This date is calculated by time analysis.
Lead (related to lag)	A time delay associated with a relationship in a project. Lag can be either positive or negative. Negative lag is sometimes called "lead."
Logic Diagram	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Logic Drawing	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Loop	In networks, a consecutive set of activities that are mutually dependent.

M

Field	Description
Master Project	A project with activities representing external subprojects.
Mean	The most common and useful measure of central tendency for a probability distribution. The mean value is the same as the "average" or "expected" value.
Median	A measure of the central tendency of a probability distribution such that there is a 50% chance of a value sampled from the distribution is less than the median.
Milestone	Activity with zero duration — must be designated as either a start milestone or a finish milestone. While Open Plan does not prevent you from placing a duration on an activity with a milestone activity type, this is not recommended.
Military Time	A means of representing time by use of a 24-hour clock.
Mode	A measure of central tendency for a probability distribution, being the most likely single value for a variable sampled from that distribution. For a theoretical distribution, the mode is represented by the peak of the curve. The mode is the same as the "most likely" value.
Monte Carlo Simulation	The technique used by Open Plan to estimate the likely range of outcomes from a complex random process by simulating the process a large number of times. Monte Carlo simulation is used as an alternative to analytical statistical techniques when the process is too complex to be readily treated by such techniques.
Most Likely Value	A measure of central tendency for a probability distribution, being the most likely single value for a variable sampled from that distribution. For a theoretical distribution, the mode is represented by the peak of the curve. The mode is the same as the "most likely" value.
Multiple End Option	The multiple end option causes time analysis to treat each end activity as if it was the end of an independent project, so that the float would normally be zero.
Multi-project Processing	A complete project represented as a single activity in a higher-level project. Open Plan uses external subprojects for multi-project processing.

N

Field	Description
Negative Float	The amount of time by which the early date of an activity exceeds its late date.
Network View	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Non-Linear Date Scale	A date scale in which the divisions represent varying time spans. In Open Plan, non-linear date scale is defined using reporting calendars.
Non-Working Day	The standard non-working day on the calendar. For example, assume that a calendar defines Monday through Friday as days on which work is normally performed. In this case, a Saturday that has not been identified as an extra work day would be a non-working day.
Normal Distribution	A family of symmetrical continuous probability distributions defined by two parameters representing the mean and standard deviation of the distribution. In Open Plan, the sampling method for normal distributions is an approximation that curtails the curve at three standard deviations either side of the mean. In theory there would be approximately a 1% chance of values falling outside of this range.

O

Field	Description
OBS (Organizational Breakdown Structure)	A hierarchical structure designed to pinpoint the area of an organization responsible for each part of a project.
Offset	The number of work periods between the start of the activity and when the resource is first required.
Open Plan Ancillary File	A resource, code, or calendar file associated with an Open Plan project.
Organizational Breakdown Structure (OBS)	A hierarchical structure designed to pinpoint the area of an organization responsible for each part of a project.
Out-of-Sequence Progress	Progress that has been reported even though activities that have been deemed predecessors in project logic have not been completed.

P

Field	Description
Pad Character	A character that is used to fill out a code in a fixed-form significant breakdown structure so that all codes are the same length.
Parent	A higher-level element in a hierarchical structure that summarizes lower-level elements.
PDM (Precedence Diagram Method)	One of the two methods of representing projects as networks, in which the activities are represented by nodes and the relationships between them by arcs.
Percent (%) Complete Work	The percentage of the work content of an activity that has been achieved. See also Budgeted Cost of Work Performed.
Percent Complete	One measure of completion used in Open Plan to determine the remaining duration of a partially completed activity.
Performance Measurement Baseline (PMB)	A baseline that is used for cost calculations. If a PMB exists, it is used even if it is not one of the selected baselines. By always using the PMB when it is available, Open Plan provides consistency and reliability.
Period End Date	The status date of a project. All progress information entered for a project should be correct as of this status date. No work will be scheduled by the time analysis or resource scheduling programs prior to this date. Another term that is used to describe the status date of a project is Time Now.
Perishable Resource	A consumable resource with an expiration date.
PERT	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Physical Percent Complete	The percentage of the work content of an activity that has been achieved. See also Budgeted Cost of Work Performed.
Placements	The automatic calculation of coordinates for activities in a network view.
Plan (Project)	A set of activities directed to an overall goal. Also, the collection of data relating to the achievement of that goal. More specifically, a network of activities or the file(s) containing such a network.
Planned Activity	An activity not yet started.
Pool (Resource Pool)	A higher level resource in a resource breakdown structure.
Precedence Diagram Method (PDM)	One of the two methods of representing projects as networks, in which the activities are represented by nodes and the relationships between them by arcs.
Predecessor	An activity that logically precedes another activity. Normally, this term refers to an immediate predecessor; that is, one directly implied by the project data.
Priority Rule	A rule used to determine the order of processing in resource scheduling algorithms.
Probability	The measure of the chance of a particular outcome resulting from a random process. If the process can be performed a number of times, then as the number of trials increases, the proportion of times that a particular outcome results should converge on a value called the probability.
Probability Distribution	The representation of the range and relative probabilities of the possible outcomes from a random process. A probability distribution may be in the form of a table, a curve, or a histogram.
Progress	The partial completion of a project or a measure of same. Also, the act of entering progress information for a project.
Project	A set of activities directed to an overall goal. Also, the collection of data relating to the achievement of that goal. More specifically, a network of activities or the file(s) containing such a network.
Project Drawing	A project drawing in which the project logic is the sole determinant of the placements of the activities in the drawing. Frequently called a flowchart, PERT chart, logic drawing, or logic diagram.
Project Logic	The relationships between the various activities in a project.
Project Templates	The feature that allows projects or parts of a project to be stored and used as building blocks in creating new projects.
Punctuated Significant Coding Structure	A coding structure in which a specific character (usually a period) is used to separate the part of the code that corresponds to the different levels in the breakdown structure.

R

Field	Description
RBS (Resource Breakdown Structure)	A feature of hierarchical resources that facilitates both roll-up reporting and summary resource scheduling by enabling you to schedule at the detailed requirements level and roll up both requirements and availabilities to a higher level.
Read Only	If you have a file open in read-only mode, other users may open the file in any mode they choose. You cannot make any changes to a file that you have open in read-only mode, nor can you see any changes made by other users. If you would like to make changes to the file, use the Save As command to save the file under a different name and make any changes you want to the new file.
Relationship	A logical connection between two activities.
Relationship Float	Open Plan permits the calculation of both free and total float on relationships, which are analogous to the float fields on the activities.
Remaining Duration	The remaining portion of an in-progress activity's duration.
Reprofiling	In resource scheduling, it is possible to indicate that the specified resource requirement profile may be modified to fit the availability without changing the total amount required.
Requested Resource	The preferred resource requirement for an activity.
Resource	An item required to accomplish an activity. Resources can be people, equipment, facilities, funding — anything needed to perform the work of a project.
Resource Allocation	An option used in conjunction with alternate resources, pools, and skills, that allows you to selectively replace a requested resource with one suggested by Open Plan. During resource allocation, you can also selectively lock the allocation of either your requested resource or the one suggested by Open Plan.
Resource Assignment	The requirement for a particular resource by a particular activity or part of an activity. Sometimes called a resource requirement.
Resource Availability	The level of availability of a resource, which may vary over time.
Resource Breakdown Structure (RBS)	A feature of hierarchical resources that facilitates both roll-up reporting and summary resource scheduling by enabling you to schedule at the detailed requirements level and roll up both requirements and availabilities to a higher level.
Resource Histogram View	A view in which resource requirements, usage, and availabilities are shown against a time scale. In Open Plan, a resource histogram can be displayed both alone and in combination with a barchart view.
Resource Level	A specified level of resource units required by an activity per time unit.
Resource Leveling	The resource scheduling process of determining scheduled dates such that neither the project completion date nor any target finishes are jeopardized while minimizing the maximum extent to which any resource availability is exceeded.
Resource-Limited Resource Scheduling	The production of scheduled dates in which the resource constraints are considered as absolute and project completions are delayed as necessary to avoid exceeding resource requirements.
Resource Locking	The objective of resource locking is to inhibit future alternate resource scheduling.
Resource Offset	The number of work periods between the start of the activity and when the resource is first required.
Resource Period	The number of work periods for which a resource is required.
Resource Pool	A higher level resource in a resource breakdown structure.
Resource Roll-Up	An option that allows you to look at resources and schedule the activities from a summary perspective.
Resource Scheduling	The process of calculating a set of scheduled dates that takes into account the resource requirements of each activity and the availability of these resources.
Resource Thresholds	In resource-limited scheduling, it is possible to specify that a particular resource may be exceeded, if necessary, by an amount not to exceed the specified threshold for that resource.
Resource Total	A specified total of resource units required by an activity over a period of time.
Risk Analysis	A technique designed to quantify the impact of uncertainty. Usually, but not necessarily, associated with the Monte Carlo simulation technique used in Open Plan.
Risk Analysis Histogram View	A view in which the results of risk analysis are displayed as vertical bars, S-curves, or tables against a date scale.
Root Calendar (Standard Calendar)	The default calendar in a calendar file.

S

Field	Description
Schedule Dates	The start and finish dates calculated by the resource scheduling program, having regard to resource constraints as well as project logic.
Schedule Variance (SV)	The difference between the budgeted cost of work performed and the budgeted cost of work scheduled at this point in time. (BCWP – BCWS).
Scheduled Duration	The scheduled duration of an activity is calculated by resource scheduling and takes into account such advanced activity management techniques as activity splitting, stretching, or reprofiling.
Scheduled Finish	The date calculated by the resource scheduling program as the earliest date on which an activity can finish, having regard to resource constraints as well as project logic.
Scheduled Float	Calculated during resource scheduling, the scheduled float of an activity is the difference between the late finish date and the scheduled finish date of the activity. In some circumstances, scheduled float may be shared with other activities in the logical flow of the project.
Scheduled Start	The date calculated by the resource scheduling program as the earliest date on which an activity can start, having regard to resource constraints as well as project logic.
Shared Mode	If you have the file open in shared mode, other users can open the file and make changes while you have it open. In shared mode, some changes are saved, while others are not: Any changes that you make to the file are stored immediately. The results of time analysis, risk analysis, and resource scheduling performed in shared mode are not saved. Because the project data is shared, there are some project-level actions that you cannot perform while in this mode: You cannot add or change an ancillary (calendar, code, resource) file. As shipped from Deltek, Open Plan does not allow you to save changes made on the Project Properties dialog box. You cannot save a file opened in shared mode using the Save command. You can, however, save it with a new name using the Save As command.
Skew	A measure of the degree of asymmetry in a probability distribution. For symmetrical distributions, the skew is zero.
Skills	A feature of hierarchical resources that allows you to assign an attribute to a resource and to define the resource requirement for an activity in terms of that attribute.
Slack	The number of time periods by which an activity can be delayed without affecting other activities in a project. See also Free Float and Total Float.
Smoothing	A resource-scheduling option that attempts to even out or "smooth" the way in which resources are assigned to activities in the following circumstances: During time-limited resource scheduling. During resource-limited resource scheduling when thresholds are in use. With the smoothing option, Open Plan assumes that even though a resource availability has been exceeded on a preceding activity, available float should be used in preference to overloading the resource again.
Splitting	In resource scheduling, it is possible to indicate that the specified duration may be divided into two or more pieces, while retaining the specified profile for resource requirements relative to this split duration.
Spread Curve	A profile that describes how the resource requirement is spread through the duration of an activity.
Spreadsheet View	A view in which data is shown in a tabular format. There are single-table spreadsheets and multi-table spreadsheets. An activity spreadsheet is always shown as one of the windows in a barchart view.
Standard Calendar	The default calendar in a calendar file.
Standard Deviation	A measure of the amount of random variation in a random variable, calculated as the square root of the variance. Same as root mean square deviation.
Standard Work Week	The working hours and days defining the basic work pattern for a calendar.
Start Activity	An activity that is not logically dependent on any predecessor activity.
Start Milestone	A milestone activity signifying the start of a project phase. If the activity duration is zero, Open Plan replaces the early and late finish dates with the early and late start dates during time analysis.
Start-to-Finish Relationship	The relationship between activities that specifies that the finish of the successor activity depends on the start of the predecessor activity. In most cases, this means that the successor activity cannot be completed before the start of the predecessor activity.
Start-to-Start Relationship	The relationship between activities that specifies that the start of the successor activity depends on the start of the predecessor activity. In most cases, this means that the successor activity cannot be started before the start of the predecessor activity.
Status Date	The status date of a project. All progress information entered for a project should be correct as of this status date. No work will be scheduled by the time analysis or resource scheduling programs prior to this date.
Stochastic	Random variation that cannot be predicted other than in statistical terms.
Stretching	In resource scheduling, it is possible to indicate that the specified duration may be increased, while the specified profile is reduced proportionately.
Subproject	An activity that represents a group of activities at a lower level of the same project and allows Open Plan to calculate its duration based on the durations of lower-level activities.
Successor	An activity that logically follows another activity. Normally, this term refers to an immediate successor; that is, one directly implied by the project data.
Suggested Resource	The suggested resource is the resource requirement for an activity that Open Plan suggests during resource scheduling.
Summary Activity	A group of activities represented as a single activity in a higher level of the same project.
Summary Resource	A group of resources represented as a single resource in a higher level of the same resource pool.
Summary Task	A group of activities represented as a single activity in a higher level of the same project.
Symmetrical Distribution	A probability distribution in which variations from the central tendency by a given amount in either direction is equally likely.

T

Field	Description
Target Date (Constraint)	Date imposed on an activity or project by the user. There are two types of target dates: target start dates and target finish dates.
Target Finish	A finish date imposed on an activity or project by the user.
Target Start	A start date imposed on an activity or project by the user.
Target Type	Open Plan allows you to specify three types of target dates for activity start and finish dates: Not Earlier Than: The earliest date on which the activity can start or finish. This constraint affects the early dates calculated by time analysis. Not Later Than: The latest date on which the activity can start or finish. This constraint affects the late dates calculated by time analysis. On Target: Combines the effects of both Not Earlier Than and Not Later Than target dates and affects both the early and late dates calculated by time analysis.
Task (Activity)	The smallest self-contained unit of work used to define the logic of a project. In general, activities share the following characteristics: They have a definite duration. They may have logical relationships to other activities in a project. They use resources such as people, materials, or facilities. They have an associated cost.
Threshold	The level to which Open Plan may exceed the availability of a resource during resource-limited resource scheduling.
Time Analysis	The process of calculating the early and late dates for each activity on a project, based on the Time Now date, the duration of the activities, and the logical relationships between them.
Time Now	The status date of a project. All progress information entered for a project should be correct as of this status date. No work will be scheduled by the time analysis or resource scheduling programs prior to this date. Another term that is used to describe the status date of a project is Period End Date.
Total Float	The maximum number of work periods by which an activity can be delayed without delaying project completion or violating a target finish date.
Total Slack	The maximum number of work periods by which an activity can be delayed without delaying project completion or violating a target finish date.
Triangular Distribution	A family of probability distributions that is triangular in shape when represented as a frequency distribution.

U

Field	Description
Uncertainty	The lack of precision in estimating or predicting the outcome of some process.
Uniform Distribution	A family of probability distributions characterized by two parameters, representing the minimum and maximum possible values. Any allowable outcome between the two extreme values is equally likely. For example, the distribution of the outcome from the throwing of a single die is uniform in the range of 1 to 6.

V

Field	Description
Variance	A discrepancy between the actual and planned performance on a project — either in terms of schedule or cost.

W

Field	Description
WBS (Work Breakdown Structure)	The breakdown of a project from the client's point of view in terms of deliverables.
Whole Relationship	A relationship in which both the predecessor and the successor activities are visible in the displayed area or printed page.
Work Breakdown Structure (WBS)	The breakdown of a project from the client's point of view in terms of deliverables.
Working Day	The standard working day on the calendar. For example, assume that a calendar defines Monday through Friday as days on which work is normally performed. In this case, a Monday that has not been identified as a holiday would be a working day.

Z

Field	Description
Zoning	A feature of Open Plan that causes activities on a network view to be grouped into horizontal bands based on one or more criteria that you specify.