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Student Packet
Developing a Decision-Making Model
Use contents of this packet as you feel appropriate. You are free to copy and use any of the material in
this lesson plan.
Packet Contents
Blank Decision Tree for Picnic Example
Large Blank Decision Tree
Weather Journal Activity – see suggested grading rubric in teaching edition. You may want to
include / handout a grading rubric for the students.
Cover Page Directions
Weather Observation Data Recording Sheet
Weather Chart Number Scales
Weather Web Site Worksheet
Homework / Blank Decision Trees for Optional Decision Trees –Step 4
Probabilistic Decision Making Tree
Problem: Where to Have a Picnic
Decision
Point
Probabilistic
Event
Outcomes
- represents a decision point
- represents a point when a random event occurs
- represents flows in the diagram – time or other
Goal: ___________________________________________________
Probabilistic Decision Making Tree
Problem: _________________________
Decision
Point
Probabilistic
Event
Outcomes
- represents a decision point
- represents a point when a random event occurs
- represents flows in the diagram – time or other
Goal: ______________________________________________
Daily Weather Journal
Objectives
Introduce students to observing and recording weather data over time.
Have students recognize daily changes in the weather.
Have students observe daily weather forecasts.
Directions
To complete the weather journal you must do the following.
1. Make at least twenty (20) daily weather observation entries (at least 10 days two
observations per day).
2. Make a cover page with the following: Name, Date, Class Period, and Weather Journal
Title.
3. Neatly draw a line graph using two variables (example – morning temperature / wind)
from the number of days you observed the weather. Use day as the x-axis and for the yaxis use the weather chart number scale of 0 to 5.
4. Write a summary about your weather observations. What patterns did you notice? What
was the highest temperature scale recorded? What was the lowest temperature scale
recorded? What did you learn? What would make this experience better?
5. Write at least two sentences about the daily precipitation forecasts you recorded.
6. Be creative and provide an additional way of presenting and discussing the data you have
collected.
7. Neatness counts.
8. Turn in all of the above in a folder.
Daily Weather Journal
Date _____________
Weather Variable
Day of the Week____________
Morning Observation
Location:
Time:
Afternoon Observation
Daily Weather Journal
Date _____________
Weather Variable
Location:
Time:
Temperature
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Wind Speed/Direction
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Wind Speed/Direction
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Cloud Cover
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Cloud Cover
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Humidity
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Humidity
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Precipitation
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
Precipitation
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
What is tomorrow’s forecast for precipitation? Where did you get this
forecast?
Morning Observation
Location:
Time:
Temperature
(enter 0, 1, 2, 3, 4, 5)
see weather chart
number scale
How did the weather change over the course of the day?
Day of the Week____________
Afternoon Observation
Location:
Time:
How did the weather change over the course of the day?
What is tomorrow’s forecast for precipitation? Where did you get this
forecast?
Weather Chart Number Scales
Temperature
0
VERY COLD –
standing water
freezes
Wind
NONE –
feel nothing, no
movement in
plants, smoke
rises straight up
Cloud Cover
NONE no clouds
Humidity
Precipitation
NONE –
feel nothing
1
COLD –
coats, heavy
jacket, pants,
shivering
LIGHT –
barely feel the air
movement, trees
barely move,
leaves rustle
2
COOL –
light jackets, sweater,
long sleeves, pants
3
MILD –
short sleeves, pants
or shorts
4
WARM –
short sleeves, shorts
5
HOT –
sleeveless, shorts,
swimsuit (sweating)
MILD –
tree leaves and small
branches move, paper
blows off the ground,
hair moves a little
MODERATE –
large tree branches
move, clothes blow
open, hair blows
into face
GALE FORCE –
walking is difficult,
tree branches
breaking off, moving
large items (boxes,
trash cans, signs
LIGHT –
few, white
feathery ,still
very sunny, light
fog
LOW –
air is dry
MEDIUM white/gray cotton balls,
light gray overcast
MODERATE white/gray almost
solid, occasional
sunshine
MEDIUM –
feel a little moisture in
the air
MIST –
feel moisture on
skin
LIGHT –
some dry spots on
concrete, dry under
trees
HIGH –
feel moisture in the
air, feels damp,
dew on the ground
STEADY –
constant flow
drippy under trees
STRONG –
large tree branches
leaning over,
whistling sound,
umbrellas blow
upward, pushes
body sideward
HEAVY gray puffy or
overcast, no
sunshine, ready to
rain
VERY HIGH –
raining or very
muggy/sticky, feels
like a wet blanket
HEAVY –
large drops, making
puddles, drains
flowing
VERY HEAVY –
gray/black solid
clouds, prepared for
heavy rains, tornado
alerts
FLOOD –
rushing down streets,
deep in ditches, flash
flood warning
Weather Web Site Worksheet
Name:
Class:
Find a web site of your choice that is concerned with weather. Answer the following questions.
1.
What is the web site address?
2.
What organization sponsors this site?
3.
How did you find this site?
4.
What is the most interesting information you learned from this website, that you would tell your
friends?
5.
What are two other pieces of weather related information that are on this site?
6.
How does this site relate to your class work on weather?
7.
What is your overall evaluation of the web site?
Very Poor
Poor
Average
Good
Very Good
Name ___________________________Date______________________Class_______________
Decision Tree Problems
For the following decision problems fill in the decision trees, provide the decision to be
made, the random event and probability associated with the event, and the payoffs.
1. You must decide to bring your raincoat to the football game or leave the raincoat at home. If you
bring your coat and it rains you will be happy and dry. If it does not rain, you will be dry, but you
will have the hassle of carrying the coat and not using it. Finally, if you do not bring the coat and it
rains you will be unhappy and wet. The weather forecast is for a 50% chance of rain.
2. The forecast is for a 10% chance of hail this evening. Your parent’s decision is to either clean up the
garage to be able to park the car in the garage, or to not clean up the garage and park outside. If it
hails and the car is parked in the garage, the car is OK, but you had the hassle of cleaning up the
garage. If the car is parked in the garage and it does not hail, the car is still OK but you did have the
hassle of cleaning the garage. If you park outside (no hassle to clean the garage) and it hails, the car
is dented. If the car is parked outside and it does not hail the car is OK and you did not have to clean
the garage.
Name ___________________________Date______________________Class_______________
3. Your teacher has stated there is a 20% chance of a test tomorrow and an 80% chance of not having a
test. Develop a decision tree associated with the decision to either study after school or play. If you
study and there is a test, you will have a passing grade. If you do not study and there is a test, you
will fail the test. If there is no test, there is no grade that day in the class. This example illustrates
that the decision does not have to be weather related.
4
There are two different roads (Baxter and River Roads) your parents can use to take you to school. In
taking Baxter Road, you have to cross a railroad crossing. If there is no train (25% chance) you will
make it to school on time. If there is a train (75% chance), you will be 10 minutes late to school.
River Road uses an overpass to cross the railroad. If you take River Road there is no chance of being
stopped by a train, but you will be one minute late for school. This example differs because it is not
weather related and the decision tree has only flow out of river road because there is no train crossing.
Name ___________________________Date______________________Class_______________
5. NASA is faced with the decision of landing the space shuttle either in California or in Florida.
Weather forecasts for both the Florida and the California landing sites are available. There is a 30%
chance of storms in Florida and a 10% chance of storms in California. If there are storms at the
landing site used, the shuttle will be damaged. If there is not a storm, the shuttle lands without
damage. NASA also incurs an additional expense of transporting the shuttle to Florida, if the shuttle
lands in California. Create a decision tree for this problem; note the chances for no storms are 100%
minus the chance of storms. Hint: your decision tree should include additional costs if the shuttle
lands in California.
6. This Saturday morning, you can either referee soccer or help your mom clean the house. You must
sign up as a soccer referee by Thursday. If you referee and it does not rain, you will earn $65.
However, if it rains, the soccer games will be cancelled and you will earn $0. You mom will pay you
$20 to help clean the house. Because you are cleaning inside, you will earn this $20 regardless of the
weather. The weatherman has forecasted a 20% chance of rain. Create a decision tree for this
problem; note the chances for no rain are 100% minus the chance of rain.
Name ___________________________Date______________________Class_______________
7. You are the owner of the Good Goof Manufacturing Company. Your company uses a machine to
make Good Goofs. The decision you are facing is whether to service the machine or don’t service the
machine. If you service the machine, there is a 1% chance of the machine breaking down, therefore,
a 99% chance of no breakdown. The cost of servicing the machine is $50. If you do not service the
machine, you have service costs, but the probability of the machine breaking down increases to 3%.
If the machine breaks down, it will cost $2000 to fix. Develop the decision tree for this problem
8. Decision trees are often more complex than the examples given in questions 1-7. As an example,
consider Antique Dealer Inc. Antique Dealer has a client that will buy an antique tractor for $5,000.
Antique Dealer Inc. has found the tractor and can either buy the tractor today for $3,000 or wait until
tomorrow to buy the tractor. Tomorrow’s price is $2,500. By waiting, Antique Dealer Inc. runs the
risk that someone else will buy the tractor. There is a 30% chance someone other than Antique
Dealer will buy the tractor today and a 70% chance the tractor will not be sold today. Develop a
decision tree for Antique Dealer’s decisions over the next two days. Antique Dealer Inc. wants to
make as much money as possible. Money made by Antique Dealer Inc. is the cost of the tractor
minus what they must pay for the tractor. Hint: the key to drawing this decision tree is for day one,
Antique Dealer must choose between buying the tractor and waiting until day two.