Case #1: Broken Bikes

We learned that Prof. Martin fell off her bike while training for her triathlon. Unfortunately, her bike cannot be fixed and she needs to purchase a new one before her race. She consulted with Coach Luna-Reyes about which bike to purchase. She identified three comparable Cannondale bikes[1]:

Slice UltegraThis is a triathlon-specific bike (time trial, or TT bike) that puts riders in a more forward and aerodynamic position. Its advantages are that it is faster (aerodynamic) and the position reduces stress and muscle fatigue in the quadriceps, making it easier to run afterwards. However, being positioned so far forward makes it much harder to handle the bike, so it cannot be used for riding in groups, in cities (which requires maneuvering around traffic), or for climbing hills.

Synapse Carbon Disc UltegraThis is an endurance road bike that is ideal for a range of road biking conditions, including riding in groups, in cities, on hills, etc. It is a great all-around road bike but not as fast as the triathlon bike.

CAAD12 Disc UltegraThis is a cyclo-cross bike with wider wheels that can be adapted for a wide range of terrains (roads, sidewalks, dirt trails, gravel) and conditions (cities, hills, etc.). It is slower than a road or triathlon bike, but a great all-purpose bike for many different types of rides.

For an additional $100, she can purchase clip-on aerobars for the Synapse and CAAD12 handlebars to make them more aerodynamic (and faster!).

After extensive research, Coach Luna-Reyes identified six criteria/objectives that are important to this decision and worked with Prof. Martin to rate them. These are in the table below.

Objective	Cannondale Slice Ultegra	Cannondale Synapse Carbon Disc Ultegra	CAAD12 Disc Ultegra
Material1	Carbon fiber	Carbon fiber	Aluminum
Price	$2,700	$3,000	$2,600
Brakes2	Rim	Disc	Disc
Versatility	Can only be used for the race	Can be used for the race and most other road riding, e.g. with friends	Can be used for the race, in any road conditions, and off-road
Speed	The fastest of all options	Faster than the CAAD12, but slower than the Slice3	The slowest of all options4
Running benefit	Yeseasier to run after the bike portion of the race	No	No

¹ Aluminum bike frames are stiffer than carbon fiber bike frames. The advantage of carbon frames is that they absorb more vibrations from the road (i.e. the impact when riding over bumps in the road), which makes the ride more comfortable. This becomes important on a very long ride. They are also a little lighter, making the bike faster.

² Cantilever rim brakes are the brakes that most people have on their bikes. To work well, they need to be cleaned often. Disc brakes are newer and their advantage is that they are very responsive and work well in many different conditions including in the rain. Riders using disc brakes can stop more quickly and safely in any weather.

³ For an additional $100, Prof. Martin could purchase aerobars to install on her handlebars. This would make the Synapse as fast as the Slice

⁴ For an additional $100, Prof. Martin could purchase aerobars to install on her handlebars. This would make the CAAD12 as fast as the Synapse

Develop a MAU model to evaluate these five alternatives (three bikes, and adding the aerobars to the Synapse and CAAD12). You will need to use your qualitative judgment to assign normalized scores for the attributes, on a scale of 0 to 100.

Do some sensitivity analysis by developing three models that use alternative weighting schemes considering these three set of values.

Neutral preference --> assign the same weight to all attributes

Maximize Triathlon Performance --> assign a weight of 50 to speed and running benefit, assign a weight of 30 to material and brakes, assign a weight of 10 to price, and assign a weight of 0 to versatility

Long-Term Benefits --> assign weights as follows: 80 to versatility, 40 to brakes, 30 to speed and material, 20 to price, and 10 to running