Managerial perceptions of project stability 941602 朱菲比 941606 洪嬿翔 941607 周佩穎 ...

Managerial perceptions

of project stability 941602 朱菲比 941606 洪嬿翔 941607 周佩穎 941614 戴琬臻 941628 陳采揚 941644 陳奕君 941655 劉若芬

ABSTRACT

941628 陳采揚

the importance of stability project outcomes. Cost, schedule, performance, and earned

value were compared to proposed measures of stability.

Stability and earned value had both importance and usefulness to the managers.

depending on program size, scope, and stage of completion and between managers depending on experience and certification level

941628 陳采揚

Stability

941628 陳采揚

• In case A, “positive” stability. the disruption is absorbed by the schedule, and the activities quickly get back to the original schedule.

• In case B, “neutral” stability. the disruption is simply arried forward throughout the schedule, neither increasing nor decreasing in magnitude.

• In case C, “negative” stability or instability .the initial disruption has caused increasing levels of delay, resulting in a change to project duration well beyond that of the initial delay.

Project Performance Measurement

941628 陳采揚

project objectives have been characterized :

cost, schedule, and performance.

Net present value and earned value measurement systems track both time and cost, or time and quality, at the same time.

Single-Dimension Measures: Cost,Schedule, Performance

941628 陳采揚

Schedule measures track the completion

of the required activities—usually in comparison to the project plan or schedule.

Various disaggregate as well as aggregate cost, schedule, and performance measures have been used for monitoring and guiding project performance.

Relative Importance of Cost, Schedule, and Performance Over Time

941628 陳采揚

One key question for the project manager to

answer is whether or not the relative degrees of importance or weights of the three generic goals change over the life of a project.

Example : assume performance is the most important of the three goals during the initial stage of the project life cycle , when attention is focused on the technical specifications on the project


941628 陳采揚

Once the specifications are set and work on the project begins in earnest, priority could shift to cost, then to schedule as the project

approaches completion. The assumption of changing performance

priorities over time has been challenged in the

literature both in nature and scale


941628 陳采揚

Members of the Project Management Institute (PMI) have been surveyed.

The project life cycle divided into four major parts (formation, buildup, main program, and phaseout )

The importance assigned to cost, schedule, and performance goals varied systematically

across the project life cycle.

941628 陳采揚

A contrary finding was provided by Tukel and Rom.

While project managers at all levels measured and responded to deviations in cost and schedule, the dominant measure of success tended to be performance.


941628 陳采揚

The “internal measures” of cost and schedule were perceived to have relatively low priority throughout the duration of the project

Quality (performance), when considered to be an“external measure” of responsiveness to customer needs, remained most important regardless of industry or project type


941607 周佩穎

Complex Measures: Net Present Value

& Earned Value

Management System

Net Present Value

941607 周佩穎

Net present value (NPV) is a measure that takes into account both schedule and cost, using the time value of money.

It is calculated by discounting (or inflating) the cost and benefit time series to the reference year and subtracting the present value of costs from the present value of benefits to yield the net present value of the investment.

Its use is affected by the selection of a discount rate, which is used to adjust the time series of benefits and costs for risk, time preferences of money, and inflation.

941607 周佩穎

The earned value management system (EVMS) for program management is designed to effectively integrate the work scope of a program with the schedule and cost elements for optimum program planning and control.

The primary purpose of the system is to support program management under the broad principles of cost/schedule control systems criteria.

The cost/schedule control system criteria established standards for the management of large-scale,long-term projects.

Earned Value Management System

941607 周佩穎

The essence of EVMS is that standards or target values (budgeted cost)can be determined or estimated,appropriate for the degree of technical,schedule, and cost risk or uncertainty associated with the program, for each scheduled element of work.

The earned value becomes a metric against which to measure both what was spent to perform the work and what was scheduled to have been accomplished.

Earned Value Management System

Alternative Comprehensive Performance Measurement Systems

941607 周佩穎

The balanced scorecard (BSC) approach to organizational performance measurement has received attention in the literature. A system applying the BSC principles to the management of projects has been proposed.

Firms involved in product development (1) already have a system of metrics for managing the projects; (2) have a need to “fine tune” the metrics to provide the proper emphasis or culture; and (3) have the ability to allow individual projects to increase or decrease emphasis on a particular metric.

941607 周佩穎

Tailored to the specific strategic needs of the firm or industry that context-unique measures must be developed.

A survey of project managers attempted to relate three “formal” controls (process control, output control, team rewards) and three “interactive” controls (team operational influence, team strategic influence, management intervention) to project performance outcomes.

Alternative Comprehensive Performance Measurement

Systems

Measures of Stability

941655 劉若芬

Stable: Project is able to absorb disruption as a result of unplanned events.

Unstable: Project is particularly sensitive to disruptions.

941655 劉若芬

There are some overlap between the multidimensional measures of EVMS and the proposed single-dimension measures of stability

Measurement of “variance” or deviation; both concepts are based on departures from plan.

Measures of Stability(2)

941655 劉若芬

The schedule represents a plan for how to best use the resources available in order to achieve some set of objectives within the constraints imposed upon

the project. When the schedule or plan cannot be

met, several direct and indirect undesirable consequences may result.

Measures of Stability(3)

The stability measures divide into two distinct groups

941655 劉若芬

offset measures : total person-days of overtime or under

time (idleness) experienced by resources used to complete the project.

deviation measures : total amount of earliness or lateness for activities in a project

Methodology

941655 劉若芬

Assess the project manager’s perceptions of the importance and usefulness of various project attributes and performance measures, primarily with respect to a new concept of stability.

Research Questions

941655 劉若芬

Q1:Have stability measures or concepts been previously used in project performance measurement?

Q2:With respect to existing attributes of overall project performance, is the concept of stability separable from, but comparable to, existing concepts?

Research Questions

941655 劉若芬

Q3:Compared to traditional measures of project performance used for project management, are some proposed measures of stability separable from, but comparable to, existing project management measures?

Research Questions

941655 劉若芬

Q4:Are the perceptions of stability and traditional measures affected by project or managerial context (project size, scope, or maturity; managerial level; experience; association with specific project)?

Q5:Of what use are the analysis results for the management of future projects?

Developing the Survey Instrument

941655 劉若芬

The survey was structured in three parts. Start with demographic questions and

two parts with the scale and the rank of items representing the constructs.

Developing the Survey Instrument

941655 劉若芬

First part: demographic questions Second part: elicited information about

the attribute or characteristics. Third part: concern specific project

performance measures.

DEMOGRAPHICS

Questions asking supervisory some information (position.age.occupational specialty…ect) and questions regarding the program (what stage of execution, size, scope, etc.)

In order to process the returned survey data on the computer, the categorical data was converted into numeric codes.

941644 陳奕君

Creating Item Scales

941644 陳奕君

The second section of the instrument used item scales and associated ranks.

1. General Attributes: Characteristics that a project or task will assume as it

is executed. Cost: How much does the project or task cost overall? Schedule (Sched): How long does the project or task

take to complete? Performance (Perf ): How many desirable features

does the project or task successfully deliver ? Earned Value (EV): “ how much progress am I

making against my original plan?”

941644 陳奕君

Stability (Stab): Measures the ability of a project or task to get “back on track” after being disrupted.

2. Specific Performance Measures: The metrics used to measure performance of a project. Cost Variance (CV): The difference between the budgeted cost of work

performed and the actual cost of work performed. Cost Performance Index (CPI): a measure of efficiency and can be used to predict the

final range of costs. Schedule Variance (SV): The difference between budgeted cost of work

scheduled and budgeted cost of work performed.


941644 陳奕君

Schedule Performance Index (SPI):

A productivity measure that can be useful in assessing how much work has been accomplished.

Activity Deviation (AD):

This measures the proportion of how much time the project is “off-track” in terms of scheduled completion.

Resource Offset (RO):

This measures how much time resources spend waiting to work or catching up on work in terms of scheduled activity.


941644 陳奕君

When items are to be judged on a single dimension and arrayed on a scale with equal intervals, a simple,linear numeric scale with extremes labeled appropriately is the most advisable method of scaling.

Respondents were provided with an appendix at the last page of the survey briefly defining each construct in addition to the instructions at the beginning of every one of the scales.


Selecting the Sample

941644 陳奕君

A survey method was used for the collection of data for this research.

Program managers in the design, development, and acquisition of aircraft and support systems would form the population of interest.

The selection of sample strata is usually based on some demographic characteristics known or suspected to have an influence on the result.

The sample was stratified according to the dimensions of authority level and project affiliation.

941644 陳奕君

The dimensions included three levels for civilian affiliation and five levels for military affiliation.

Participants were selected randomly from within each

stratum to conform to proportional representation.

Selecting the Sample

Sample-Size Determination

941644 陳奕君

Sample size determines the degree of statistical confidence available for analysis and interpretation.

When population variance increases, sampling error

increases and sample reliability decreases. Normally, a size of 30 or less would not provide

certain practical results. Because the people in the system program offices

are busy, and they work with sensitive information, they might not be willing to share information by means of surveys.

Initial Analysis and Reliability

941606 洪嬿翔

For tracking purposes and to increase response rates, the randomly assigned name list was used to make follow-ups.

Based on the response rate and the expected number of returned usable questionnaires, directed(within strata), random resampling was performed, and additional surveys were mailed as required.

Collecting and Processing the Data

941606 洪嬿翔

Incomplete, unusable, or blank questionnaires were set aside as declined to participate.

Monitoring was performed to guard against nonresponse bias, by analyzing the demographic subcategories (within the strata) to check for representation of completed responses.

The received survey percentages within the sampling strata were generally in accordance with the overall response rate.

Collecting and Processing the Data

941606 洪嬿翔

The response rates and proportionality were considered sufficient for the purposes of this research, although some underrepresentation appears in the higher level of authority for the military affiliation.

Descriptive Statistics, Means, and Ranks

941606 洪嬿翔

Paired-difference t tests were run to determine the significance of the difference.

scaled “importance” means and p values in the lower- left quadrant of the table

scaled “usefulness” means and p values are indicated in the upper right quadrant of the table.

Values of p that are smaller than 0.10 are indicated in bold type.


941606 洪嬿翔

The results indicate that significant differences exist in the minds of the respondents as to the relative importance and usefulness of the various project attributes, according to the order indicated, between most of the attributes.


941606 洪嬿翔

Similar agreement was found between scale means and ranks with respect to both importance and usefulness for the performance measures

scaled “importance” means and p values in the lower- left quadrant of the tablescaled “usefulness” means and p values are indicated in the upper right quadrant of the table. Values of p that are smaller than 0.10 are indicated in bold type.


941606 洪嬿翔

There was no deviation in relative order between scaled or ranked mportance or usefulness (most to least): cost variance, schedule variance, cost performance index, schedule performance index,activity deviation, and resource offset.

Reliability Analysis

941606 洪嬿翔

Constructs representing each of the five attributes and six performance measures were created from the importance, usefulness, scale, and rank data.

In order to check the internal validity of the combined constructs, Cronbach’ s alpha was used.

While reliance on this measure alone is somewhat, it is suggested that a Cronbach’ s alpha value of 0.7 or greater (as a rule of thumb) is an acceptable level of agreement.

Reliability Analysis

941606 洪嬿翔

Describes the Cronbach’s alpha values along with the common interitem correlation and overall model significance (x2 test) values for the variables from both general project attributes and specific performance measures.

For both the attributes and measures, it is, therefore, concluded that sufficient item, scale, and construct validity (internal, convergent) exists to support additional analysis.

Exploratory Factor Analysis

941606 洪嬿翔

Based on the positive results from the reliability analyses, factor analyses were performed on the attributes and measures.

Exploratory factor analysis was used to distill the factors out of the data matrix with no a priori assumption of variables loading against any particular construct

SPSS v. 12.0 for Windows was used to run the principle components model, with eigenvalues greater than 1.0 for extraction, followed by a Varimax rotation with Kaiser normalization.

Exploratory Factor Analysis

941606 洪嬿翔

The five factors provided a cumulative total variance explained of 77%

While internal (convergent) validity appeared to be demonstrated by the reliability analysis discussed previously, discriminatory validity was not supported at this time.

Additional research is suggested in this area.

ANALYSIS OF VARIANCE•The initial phase of the analysis :

–Reliability and Validity

•The final phase of analysis :–performed to assess the degree to which the stability constructs exhibit behaviors different from the traditional measures based on the environmental characteristics of the project management situation.

941614 戴琬臻

The relationships between the attributes and characteristics

941614 戴琬臻

About Table8

941614 戴琬臻

1. There are positive and statistically significant relationships between the managers’ career experience (CXP), program experience (PXP), and acquisition professional level (APL).

2. The standardized coefficients (created by the factor analysis) between the project attributes create zero or near-zero correlations and unit significance scores.

3. The cost attribute appeared not significantly correlated with any of the situational characteristics. (The exception to this is the relationship between cost and stage of completion )

4. As experience increased, the perceived importance and usefulness of earned value increased.

About Table8

5. The nonparametric test found a relationship between performance and career experience in addition to certification level.

6. Stability was positively related to all of the attributes except project size..

7. The project attribute of schedule was negatively correlated with both types of experience.

8. 6 and 7 are opposition. This information supports, perhaps indirectly, that stability and schedule are indeed separable constructs from the perspective of the project managers surveyed.

•Analysis of variance (ANOVA) was performed with the univariate procedure in SPSS. Based on an inspection of the correlation results, only the most promising characteristics were selected for study.•Two independent variables were selected to represent the environmental characteristics (program size and stage of completion), and two were selected to represent project managers’ characteristics (career experience and certification level).

Univariate ANOVA

941614 戴琬臻

Results

941614 戴琬臻

Q1: Have Stability Measures or Concepts Been Previously Used in Project Performance Measurement?

Answer: It is concluded that additional study on the

application of the concept of stability in project management would provide a contribution to theory and practice in this discipline.

941602 朱菲比

Q2: With Respect to Existing Attributes of Overall Project Performance, Is the Concept of Stability Separable From, but Comparable to, Existing Concepts?

Answer: Stability exists as an attribute and is separate

from existing concepts. Both convergent( 收斂 ) and discriminant( 判別式 )

validity( 正確性 ) were found for the construct of stability.

941602 朱菲比

Q3: Compared to Traditional Measures of Project Performance Used for Project Management, Are Some Proposed Measures of Stability

Separable From, but Comparable to, Existing Project Management Measures?

Answer: Proposed measures of stability exhibited

convergent validity. Discriminant( 判別式 ) validity was not established

separating the measures from more traditional measures, with the exception of the activity deviation( 偏差 ) construct( 建立 ).

The traditional measures did not exhibit discriminant validity.

941602 朱菲比

Q4: Are the Perceptions of Stability and Traditional Measures Affected by Project or Managerial Context (Project Size, Scope, or Maturity; Managerial Level; Experience; and Association With Specific Project)?

Answer: The importance and usefulness of the stability

attribute was positively correlated with the project managers’ experience (both career and project), the professional certification level of managers, and the stage of the project life cycle.

The nature( 性質 ) of these relationships was different from the relationships between the situational characteristics and the other project attributes.

941602 朱菲比

Q5: Of What Use Are the Analysis Results for the Management of Future Projects?

Answer: If the manager cannot measure stability in a meaningful

sense, the utility of such a concept is limited. When appropriate measures are developed, the next

step is to determine what trade-offs( 權衡 ) exist for managerial decision making between the accomplishments( 成就 ) of various project outcomes, including stability.

Scheduling or execution decisions might be made that value stability over cost or schedule.

941602 朱菲比

Conclusions, Summary, andRecommendations This research investigated the managers’

perceptions of the importance of stability to overall project outcomes.

The assessment( 評估 ) was based on both the general attributes of management for the activities in a specific program and the specific measures being employed by the managers.

In this research, the scope was limited to the management of relatively complex, large-scale, long-duration projects.

941602 朱菲比

Conclusions, Summary, andRecommendations

Projects studied involved the design, development, and delivery of military( 軍用 ) aircraft( 飛機 ) and support systems.

The research results were applied to the five research questions, and the questions were answered.

Additional notes on project performance measurement and inputs from the respondents will be given.

941602 朱菲比

Additional Observations

1. Risk assessment and task management were offered with average importance and usefulness.

2. For software development and acquisition projects, innovativeness( 革新 ), subcontractor( 外包商 ) management, and experience level were noted as being important attributes.

3. The nature of the contract paying the vendors of a project plays an important role in deciding which performance measure to choose.

941602 朱菲比

Additional Observations The cost, schedule, and performance attributes turned

out( 結果 ) to have the greatest importance and usefulness, followed by stability and earned value.

Composite( 合成的 ) measures such as cost variance, cost performance index, schedule variance, and schedule performance index led the stability measures of activity deviation and resource offset.

An assessment of managers’ perceptions of the importance of stability to overall project outcomes appears to be comparable with the traditional project objectives.

941602 朱菲比

Relationships detected1. The importance and usefulness of cost decreased as the

project completion stage increased.

2. The importance and usefulness of earned value increased as manager experience increased.

3. The importance and usefulness of project performance (quality) increased as project manager certification level increased.

4. The importance and usefulness of the project schedule decreased as project manager experience increased.

5. Finally, the importance and usefulness of the new project attribute stability increased as project manager experience, the certification level, and the project completion stage increased.

941602 朱菲比

Recommendations A recommendation arising( 產生 ) from this research

would be the expansion( 擴展 ) of the scope to a variety of projects, especially based on the contract types.

The managers’ perceptions in a larger population,

with refined( 精確的 ) definitions and measures of stability to consider. It is believed that the extension of the targeted population would yield more reliable and generalizable results.

Managerial perceptions of project stability 941602 朱菲比 941606 洪嬿翔 941607 周佩穎 ...

Documents

Transcript of Managerial perceptions of project stability 941602 朱菲比 941606 洪嬿翔 941607 周佩穎 ...