Case Study 2
The Helicopter Experiment
Case Study Overview
The goal of this mini experiment is to design a paper helicopter that remains aloft the longest when dropped from a certain height. You should conduct this experiment in groups (same as before or different).
A prototype of a paper helicopter is provided. The response variable of interest is flight time, the elapsed time between launch and when the paper helicopter hits the ground. There are many factors that may affect the flight time, such as the length or width and/or number of the rotors, the length or width of the body, the use (or not) of a paperclip, the paper type etc.
The goal of this mini experiment is to maximize the flight time of the paper helicopter by choosing the optimal levels of the factors you consider.
Once you decide which factors to use, you need to design and run the experiment. The design should be a 2k−p (fractional) factorial design, where k and p depend on the factors you choose (p can be 0). You are also allowed to introduce blocks, if needed. To run the experiment, you need to construct different paper helicopters (one for each factor level combination) and record the time they remain aloft before hitting the ground from a fixed height. Once you record your results, you need to run the appropriate analysis in SAS and draw conclusions.
In the end, you should summarize your findings in a 3-page report, which you will submit on Gradescope.
We are also going to have an in-class competition in which the group with the helicopter that stays aloft the longest will win extra credit for the case study!
Dates & Deadlines
Project report is due on April 29 @ 11.59pm. The in-class competition will be also on Monday, April 29.
STAT 424 Case Study 2 Spring 2024
How to construct the Helicopter
1. Cut out the rectangular shape of the helicopter on the solid lines.
2. Cut one-third of the way in from each side of the helicopter to the vertical dashed lines on the solid line.
3. Fold both sides toward the center creating the base. The base can be stapled at the top and bottom. Try to be consistent about where the staples are placed. Use a paper clip to add some weight to the body.
4. For long-rotor helicopters, cut down from the top along the solid center line to the hori- zontal dashed line.
5. For short-rotor helicopters, proceed as in step 4, but cut the rotors off along the horizontal line marked.
STAT 424 Case Study 2 Spring 2024
STAT 424 (Spring 2024) - Case Study #2 - Grading Rubric
Area of Assessment
Poor (1 point)
Average (2 points)
Good (3 points)
Excellent (4 points)
Introduction/ Experiment Description
Inexistent introduction.
Lack of statement of research questions. No description of the experiment.
Very brief introduction to the problem. Statement of research questions is vague.
Not all experimental steps are documented.
Clear introduction to the problem. Precise statement of research questions. Most of the experimental procedure is described.
Clear introduction to the problem. Precise statement of research questions.
Experimental procedure is described in great detail.
Experimental design & Factors considered
No specific design selected. Generic choice of factors and levels; no justification.
No justification for the chosen experimental design. Generic choice of factors and factor levels.
Brief justification of the experimental design selected. Brief justification for the factors (and levels) selected.
Detailed explanation and justification of the experimental design selected. Several factors selected with detailed reasoning.
Statistical analysis procedure
Incorrect statistical analysis. Sloppy presentation. Notclear experimental process. No justification/comments.
Not sufficient justification for the use of statistical measures used. Not enough comments during the analysis. Protocol was not strict enough - A lot of variation was left unexplained.
Correct statistical measures used. Brief discussion of protocol, generic comments regarding decisions made during the process.
Correct statistical measures used. Detailed discussion regarding protocol, execution and decisions made during the process.
Experiment Conclusion
Decision rule and conclusion are incorrect.
Decision rule and conclusion are ambiguous.
Decision rule and conclusion are slightly vague.
Decision rule and conclusion are clearly stated.
Comments
No comments or remarks about the experiment are made.
Comments made on the experimental process are only trivial and non- informative.
Clear comments are made on the experimental process.
Insightful comments about improvements of the experimental procedure are made.
