Course: Resource Estimating (Construction Engineering)

Topic: Introduction to Estimating, Types of Estimating

Type: In-class activity / Teaching Demonstration/ Bidding Game

Deming's Bag of beads (3200 white, 800 red)

Deming's experiment paddle

Scale for weighing beads

Points system for bidding (to emphasize risk assessment)

Note: Deming's red bead experiment is a renowned simulation created by Dr. W. Edwards Deming to illustrate the inherent variability in systems. I used Deming's experiment in my Quality Management Class to help students grasp the importance of systemic improvements over individual performance evaluation. However, in this demonstration and bidding game, I've employed Deming's tools for a distinct purpose. The use of Deming's tools offers two distinct advantages: they are readily accessible for educators, and incorporating them in this demonstration will encourage faculty to implement them for their original purpose in other Construction Engineering courses.

Step 1: Introduction and Initial Estimation

Present the bag containing 3200 white and 800 red beads, representing components in a simplified construction project. Ask students to visually estimate the number of red and white beads, and record their initial estimations.

Step 2: Bidding Process

Establish a point system (e.g., 1 point for white beads, 2 points for red beads) to guide the bidding process. Explain to students that these points represent the cost of conducting each white and red bead, respectively. Then, introduce the bidding element to the game. Each student has the opportunity to submit a confidential bid on the bag of beads. For example, a student can write I will do the whole project for 5000 points. The student who offered the lowest bid will get the project. The profit (or loss) of the student will be determined based on the points system. In this case, the student who offered 5000 points, will earn 200 net points because the cost of the project to the student will be 3200*1 (for white beads)+ 800*2(for red beads)= 4800 points. Do not reveal student points until the end of the game.  

Step 3: Sample Extraction with Deming's Experiment Paddle

Introduce Deming's experiment paddle and its purpose in simulating additional data acquisition. Randomly select a sample of 50 beads using the paddle. Display the sample and disclose the actual counts of red and white beads. Highlight that this step mirrors the process of obtaining supplementary information during estimation.

Step 4: Estimation Revision

For the second bidding round, allow students to adjust their initial estimations based on the sample data. Encourage them to contemplate how the sample results affect their overall estimate. Repeat the bidding process from step 2.

Step 5: Weighing the Beads

Introduce the scale's role in the demonstration. Weigh both the 50-bead sample and the entire bag separately. Share the weights with the class, emphasizing the significance of this step in refining estimates.

Step 6: Final Estimation

In the third bidding round, have students make their final estimations, incorporating all provided information. Remind them to consider the impact of the additional data. Repeat the bidding process from step 2.

Step 7: Debrief and Discussion

Conclude the demonstration by facilitating a debriefing session.

Discuss the process with the students, emphasizing the significance of gathering comprehensive data for accurate estimating. Reveal the number of points that each student would have received or lost if they were chosen for the project.