Northern Science

Chapter 6

VARIABLES

To solve a problem or answer a question, we try to develop an experiment. What is causing this outcome? Why is this happening?

In an experiment, variables are influences or causes that can "vary," or be changed.

You do well on a test. What are the variables that brought about that result?

• You studied a lot (hard work).
• The teacher likes you and corrected your work kindly (favoritism).
• You cheated (lack of honesty).
• You ate and slept well before the test (health).
• This is your third time in the sixth grade and you remember the test from last year and the year before (repetition).

These are all possible variables to your success. Which one affected the test score the most? You must determine this so you can do well again. (I do not recommend cheating or three years in the sixth grade.)

For years, I noticed that someone in our house was finishing all the juice. It didn't matter how many times a day I made juice, the container always seemed to be empty. I watched closely, but couldn't tell who was drinking it. All five children were young then, Anna, Elizabeth, William, Rachel, and Wayne. There was no way for me to prove who was drinking it. Finally, one of the children went to stay overnight with a friend. The juice supply was untouched. Then we knew who was drinking it all. (I won't mention names or I'll get in family trouble.) As long as there were five children (variables) who were suspects, there was no way to tell who was the secret consumer. Each child was a variable. As soon as the cause was removed, and there was a big change, we could be very sure.

A great mystery story will introduce variables (characters) and leave the reader the task of trying to determine which variable committed the crime. All the characters are introduced, and facts about each one are given. The emphasis of the facts will lead the reader to think one of the characters is the guilty party, but the important facts are hidden in the story somewhere. The reader is surprised to discover "who (which variable) done it" at the end of the story.

Too often, people will attribute an outcome to a variable that isn't the cause of the problem. I once heard a hunter come home empty handed. He said, "My sight moved." His sight didn't move. He needed to learn how to shoot!

A young man complained when he returned from a boat trip to a distant lake. He smashed the lower unit of his outboard motor. He said, "A rock hit my motor." I was stunned. I asked him, "Among you, the rock, and the motor, which one is supposed to have sense?" He was blaming the rock and wasn't willing to accept the responsibility for damaging the motor. His understanding of how to pilot the boat was the variable that could have avoided destroying the lower unit.

Campfire coffee always tastes better to me than perked coffee or drip coffee in the house. In order to test this, I had do an experiment. I identified the variables: amount of coffee, type of coffee, source of water, amount of water, type of cup and the same people to test the coffee. The location the coffee is being tasted might also influence the response, whether in a coffee shop, around a campfire, or in the kitchen beside a warm wood stove etc. I did a scientific test to see which method was best.

Years ago, trappers spent the whole winter with a single partner. Often, conflict would result. They would end the winter without talking to each other. Sometimes one of them came out of the woods and the other one did not.

If two trappers were alone together, and one of them was murdered, there is no question who did it. There was only one variable. However, if there were three trappers in the same area, and one was murdered, there was a question regarding which of the remaining two did it. It would then be hard to determine which of the two variables was the cause.

Consider this: You are baking. The cookies burn on the bottom. You say, "The oven was too hot."

Is this the only variable that affects how the cookies turn out? Perhaps

• the pan was too thin.
• you didn't grease the pan enough.
• the pan was too high or low in the oven.
• the batter was too thick or thin.
• you left them in too long.

All these are variables that affect the way your cookies baked. How can you know which one, or ones influenced your cookies the most?

It's hard to say without doing an experiment. It could have been any one, or a combination of the above.

Frank sang a song. People said he sounded wonderful. He said, "I have a great voice." Can he be sure this is true?

Perhaps

• it was a great song
• the people liked the accompanying music.
• they felt sorry for him and were being polite.
• or, maybe he really does have a great voice.

You meet someone new. He doesn't seem friendly to you. You think, "There must be something wrong with me."

Maybe he

• was having personal problems that day.
• liked you but doesn't communicate well.
• was afraid you wouldn't like him.
• liked you, but is interested in different topics of conversation, (music rather than sports).
• has social problems.

Which of the above do you think are most likely to be causes?

All of the above are examples of variables that affect situations. Before we can identify what is causing things to happen, we must be aware of all the variables influencing the situation.

We play cribbage. When we win, we call it skill. When we lose, we say the other player has good luck. Which is it?

Maybe

• the opponent cheats.
• the opponent is skilled or unskilled.
• you missed counting some points.
• the game involves a little skill and a little luck.

Harry surprised everyone when he won the winter carnival snowmachine race. They said he was the best driver. Harry knew that there is more to winning than good driving.

• He used high quality gasoline.
• He tuned his engine.
• He used his smaller machine that had a cleated track for the hard packed trail.
• His smaller machine was better for the obstacles than bigger ones.
• He got a good night sleep and ate a good light meal before the race.

Of course he drove well, but he made sure that all variables were in his favor.

One family cuts fish in the summer and has good fish. Another family has fish, but it doesn't taste as good. What are the variables?

• If fish are cut too thick they sour.
• If the salmon aren't cared for before cutting they sour.
• If they are cut too thin they are very dry.
• If the smokehouse is:

on damp ground
too enclosed to get enough fresh air
leaky...

• the fish will not dry well.
• If the smudge fire isn't kept going the fish:

will tend to have maggots
can sour, especially in rainy weather

The location of the net will affect the quality of fish.

• Fish caught early in the season will be in better shape than those caught at the end.
• Salmon from one side of the river might be in good shape. Salmon from the other side might be about to spawn in a nearby tributary.
• Some people smoke with cottonwood.
• Some use birch.
Others use alder.
Some don't smoke them at all.
• Some people soak their fish in salt brine before hanging them.
• Some use sugar.
Some use both salt and sugar.
• Fish put in the cache during wet weather will tend to mould.

These are all variables in making good fish.

Talk with old timers in your town or village. Ask them about the above. Which do they think are most important? What other things affect dry fish?

Larry wore the same basketball shirt without washing it. He made over ten points per game for several games. His mom washed the shirt without Larry knowing it. The next game he made two points. Larry said washing the shirt caused him bad luck.

What other variables are involved in scoring?

• How many minutes did he play?
• Did his teammates pass to him?
• Who was playing defense against him?
• Did he sleep and eat well?
• Was he emotionally "up?"
• Were the referees fair?

Give ways to increase his chances of scoring better the next time.

Which of the variables listed above do people usually blame if they lose?

What are the variables involved in a team winning?

• Good team spirit.
• Lots of practice
• Good rest and food.
• Good rhythm
• Good coaching

Mike and Sonny were basketball players. At halftime, Mike drank Gatorade, and Sonny drank water. At the end of the third quarter Mike was thirsty again. Sonny wasn't thirsty and said that water is more satisfying than Gatorade. Is this necessarily true? What other variables are involved?

Fred and Howard went hunting caribou together. Fred shot three caribou with his 30-30. Howard shot three with his .308, but one ran away. Fred said that his 30-30 is better for caribou. Is this necessarily true?

Which of the following variables do you think could also have influenced the hunt.

• Who is the better shot?
• Where were the shots placed on the animal?
• How far away was each hunter from the animals?
• How big were the caribou?
• What grain bullets were used?
• Were the bullets hard or soft nose?
• Was that animal particularly tough?

There is no perfect boat design because there are so many different uses for boats. A fishing boat must safely carry a large load and be able to set long nets. A hunting boat might be built for very shallow water or easy maneuvering. A boat used for whaling must be quiet, easy to paddle, and good in ice. To design a boat, we must ask:

What kind of water will the boat operate in? Waves, shallow or swift current?

How much load will it carry?

How big is the motor to push it?

How often will it be used?

How heavy or light must it be? Will it be run in ice, or pulled overland?

How much can the builder afford to pay?

Will the boat be transported, or left in the water?

What materials will be used in it's construction? etc.

All of the above must be decided upon before the variables of boat design can be determined. The variables are: shape, length, width, height and angle of sides, shape of the bow and hull, materials and operating conditions..

There are different kinds of airplanes. There are different requirements that people have of a plane. List some of the differences in planes and why they are made the way they are. Planes are made for different purposes:

• Short takeoff and landings on small airstrips
• freighting
• passengers
• IFR and night flying
• economy for the individual owner
• versatile for wheels, skis, floats Etc.

Why are some stores successful and others not?

Why are some people better hunters than others? What are the variables?

Lisa has won many local races as a dog musher. Her dogs look healthy, but they lack the happiness they had when they were winning the races. She is concerned that their attitude will effect the next race. Which of the following variables do you think make the most difference?

• amount of training exercise.
• time of day of training.
• amount of serious training compared with fun trips (boredom).
• amount of personal time she spends with them.
• different diet and vitamins.
• parasites.

Ask someone in your community who knows about dog mushing what he or she does to get the dogs out of a bad attitude.

Harold wants to lose weight. He watches his diet closely. He seems to eat the same amount of food, but some weeks he gains weight and some weeks he loses weight. Can you think of other variables involved in weight loss besides the following?

• amount of exercise.
• methods of monitoring amounts of food
• type of food. The amount may be the same, but how rich are the foods he's eating?

Some people say it will flood when the river breaks up this year. Some say it won't.

Which of the following variables do you think are most influential?

• amount of snow in the mountains.
• thickness/rottenness of the ice at the time of breakup.
• how high the town or village is above the riverbank.
• contour of the land around the town or village.

is the land flat, or
is the town where mountains come together or
is the flow of the river through or away from town?

• rate of melting and runoff.

Which of the above variables do people control? How do people prepare for a flood?

Ask old timers in your area what they think are the major causes of flooding.

Ann was frustrated. She couldn't sew as well as her sister, Margaret. She wanted to quit sewing, but then she wondered what Margaret did that she didn't do. What do you think are the variables to sewing well.

A student is discouraged in school. He has always been a slow learner. He wants to be a bush pilot but feels that he isn't smart enough to pass the private pilot's flight exam.

Which of the following variables are most important in his passing the test? What can he do in response to each to improve his chances of passing the test?

• intelligence.
• good study skills.
• knowing the words (vocabulary) used in aviation.
• knowing about weather and maps.
• willingness to work hard.

Which of the following would help him pursue his career goals?

• buy and study aviation maps, hang them on the wall.
• talk to pilots.
• listen to radio frequencies that monitor ground-to-air conversations.
• get video tapes on learning to fly.
• read about the weather and watch weather on the news every night.
• read the life stories about other people who have learned to fly.

None of us control the amount of intelligence we were born with. Motivation plus good work and study skills are most important.

George is shorter than anyone in his class. He thinks it is because of his diet. He tries to eat better food, but he still doesn't grow.

Which of the following variables in growth do you think might be effecting him the most? How could he narrow this down?

• genetics
• age relative to the rest of the class.
• rate of maturity. Did his mom and dad mature early or late?

Maria traveled her dad's trapline by snowmachine. He was surprised to see her at the cabin. He had a very hard time getting there. He said that she must be a better driver than he is.

Is this necessarily so? Which of the following variables could have strongly influenced her performance?

• Different snowmachine and track size.
• Different snow conditions. (He already broke trail.)
• Her weight is less than his.

Joe tries to make it upstream to fishcamp on five gallons of gasoline. His brother regularly makes it on five gallons. Joe ran out of gas, and blamed the outboard motor. Is it necessarily the fault of the motor? Which of the following variables strongly influence gas consumption.

• Which boat did he use?
• Which motor did he use?
• Was the prop new or old?
• How much load did he take?
• How much wind was there?
• Did he travel in the middle of the river, or hug the banks and bars where current is slack?
• Did he run full or half throttle?
• Have recent rains caused the current to be more swift?

Mark went hunting in September and didn't see any moose or caribou. He said that he had "bum luck".

Which of the following variables could have influenced his hunting success?

• How often did he go hunting.
• What locations did he hunt? Does he know the good places?
• Did he camp out every night, or return home to sleep in a warm bed?
• What time of day did he hunt?
• Was he quiet or noisy?
• Does he know how to call moose?
• Does he know how to hunt with the wind in his favor?
• Did he check lakes, and climb hills, or just cruise the river?
• How was he dressed? Was he well camouflage?

Traditional people would ask how he had treated the animals in the past. Did he share his catch with others? Did he waste?

 Aldemia said his house is too cold. He burned three cords of wood more than his neighbor. Which of the following variables could have affected the heating of his house the most? How much insulation is in the walls, floor and ceiling? Is the house banked with dirt or snow in the winter? How often are the doors and windows opened during any given day? How big is his house compared to his neighbor's? How high are the ceilings? How many windows are there? What quality are the windows? Is his house more exposed to the north wind? What kind of wood was he burning: birch, green spruce, dry spruce, etc.? What kind of stove does he have? Is it more or less efficient than his neighbor's? How hot does he keep his house. Is there a fire all night? Is there any chance his neighbor "borrows" wood at night? Which of the above are likely to influence his wood supply the most? Ask the old timers in your area what they think is most important.

Aaron always seemed to get a shock when he touched the doorknob. His sister Miriam seldom did. He said that it was due to his "electric personality".

What other variables could have caused this?

What causes static electricity?

Sergie had trouble getting reception on his favorite radio station. He thought for a long time and concluded that the following were variables in radio reception.

• location of the radio in the house.
• time of day or night.
• strength of the signal from the station.
• hills or mountains between him and the transmitter.

Which of the above was he able to control? If you were Sergie, what would you do to find out which variables were influencing the reception the most?

I would test antenna direction first. This is the easiest. Then I would experiment with antenna length. Tired batteries are sometimes the cause.

Nighttime radio has less interference from the sun, but he can't control the sun, nor can he control the strength of signal from the radio station or mountains in the way.

He could move the radio around the house, but he is probably more comfortable in one place than in others.

Three people go trapping on their own traplines.

• One person makes \$1,500.
• Another person makes \$752.
• The third person barely managed to pay his fuel bill.

What variables influence the results?

There used to be many moose in the country. Now they are scarce. What are the variables involved?

Which has the greatest impact? Rate the answers from one to ten for your area.

Electricity costs \$.40/KWH in one village and \$.32 in another. The teacher who just moved into the first village said that the local power company must be greedy. What variables go into the cost of electricity in a town or village? Research your local power company for the impact of each variable on your electric bill.

Sam needs his outboard motor to go fishing. He changed the spark plugs twice and it still doesn't start. What other variables influence the running of an outboard?

QUESTIONS

1) Variables are____________________.

2) Good science involves _____ , ________, ______, and _______.

3) What are the variables involved in producing good dry fish?

4) Predict what would happen if you do an experiment and don't identify all the variables.

6) What similarities are there between the hunter who missed the moose and the boy who blamed the rock for ruining his lower unit?