The case study revolves around a construction project for a new manufacturing plant. The project manager, Gary Johnson, is facing challenges with estimating the project's costs and schedules accurately. Despite having a detailed work breakdown structure $($WBS$)$ and historical data from previous projects, the estimations provided by the project team vary significantly from the bids submitted by contractors. This inconsistency in estimates is leading to budget overruns and delays in project completion.

Impact on Schedule, Cost, and Scope:

The identified problem of inaccurate estimation affects the project's schedule, cost, and scope in several ways:

Schedule: Inaccurate estimation may lead to delays in completing project activities, disrupting the overall project schedule and potentially causing delays in project completion.

Cost: Inaccurate estimation results in budget overruns as the actual costs exceed the estimated costs, impacting the project's financial performance.

Scope: Budget overruns and schedule delays may force the project team to make compromises or cut corners to stay within budget and meet deadlines, potentially compromising the project's scope and quality.

Definition of Critical Path and Impact of Identified Problem:

The critical path in project management represents the longest sequence of dependent activities that determine the shortest possible duration to complete the project. Any delay in activities on the critical path directly affects the project's overall duration.

The identified problem of inaccurate estimation may affect the schedule's critical path by:

Underestimating the duration of critical path activities, leading to delays in completing these activities and consequently extending the project's overall duration.

Overestimating the duration of non$-$critical activities, which may lead to misallocation of resources and unnecessary delays in the critical path activities.

$($Source: PMI, $2017)$

Assessment of Estimating Method:

The estimating method used in the case study appears to be flawed, as it results in significant discrepancies between estimated and actual costs. One possible reason for this could be the reliance on historical data without adequately considering unique project characteristics and external factors that may influence costs. A more robust and accurate estimating method, such as parametric estimation or analogous estimation, could be recommended. These methods involve analyzing historical data along with other factors such as project complexity, resource availability, and market conditions to generate more reliable estimates.

$($Source: Project Management Institute, $2021)$

Pros and Cons of the Extant Estimating Process and Recommendations for Changes:

Pros of the extant estimating process:

Utilizes historical data for estimation.

Provides a structured approach through the use of a detailed WBS$.$

Cons of the extant estimating process:

Fails to account for unique project characteristics and external factors.

Results in significant discrepancies between estimated and actual costs.

Recommendations for changes:

Incorporate additional estimating methods such as parametric or analogous estimation.

Conduct sensitivity analysis to identify and mitigate potential risks and uncertainties in estimates.

$($Source: Wideman, $2015)$

In conclusion, addressing the issues with the estimating process is crucial for improving the project's schedule, cost, and scope management and ensuring successful project delivery.