the scientific method in science we use a specific process, called the scientific method to gather...

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The Scientific Method In science we use a specific process, called the scientific method to gather information and answer scientific questions.

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The Scientific MethodIn science we use a specific process,

called the scientific method to gather information and answer scientific questions.

The Scientific Method

ObservationPredictionHypothesisExperimentOrganizing and Analyzing the

DataDrawing Conclusions

Observation Observation is when we use our 5 senses

to see and record things. Observation only involves sensing and

recording, NOT drawing conclusions.

We can use tools to help us to observe. We can record with writing, drawings,

photos, measurements, or sound recordings.

What are the most useful senses in science? Which are the least?

Predictions A prediction is a logical statement of what

will occur in a given situation. After an experiment we never change a

prediction, we just evaluate if it was correct.

Some great scientific discoveries have happened by accident or from predictions being wrong

Hypotheses A hypothesis is a testable explanation or

prediction which uses the words “If” and “Then”.

Example: If ______________ happens, then __________ will happen.

It is more than just a guess and is based on observations.

Experiments An experiment is a procedure used to test

a hypothesis. It includes several essential parts:

Dependent Variable Independent Variable Experimental Group Control Group

Dependent and Independent Variables An independent variable is what we are

testing. The dependent variable is what we are

measuring. It is dependent on what we are testing.

Let’s try some examples: Which grows faster, a plant in the sun or a

plant in the dark? Which is faster, a lion, a tiger, or a bear? Who likes cookies more, Cookie Monster or Mr.

Harlacher?

Experimental and Control Groups We divide an experiment into two or more groups. A control group is when everything is run as

normal. Nothing is changed. An experimental group has only one thing

changed. Why do we change only one thing?

Let’s look at some examples: Which grows faster, a plant in the sun or a plant in the

dark?

Does an athlete perform better drinking Gatorade or water?

If students study more, will they get better grades?

Organizing and Analyzing Data Next, data must be collected from the

experiment. Once again we draw no conclusions here.

This means collecting data and organizing it in a way that makes sense. We often use a graph or table for this. Some types are: Table-Simply organizes the data.

Bar graph-Shows the results in columns

Line graph-shows the data in a mathematical plane with axes.

Pie chart-Shows all the data at once in comparison to the whole.

Pictogram-Similar to a bar graph, but with pictures to represent data.

Scatter Plot- Shows the data points only on a graph,

Drawing Conclusions An examination of the data is made to

evaluate if the hypothesis was correct or not. It does not matter if the hypothesis was

“right” or “wrong”. The result is valuable either way.

Mathematical analysis such as an average/mean, standard deviation, or t-test can be used to see if any difference between the control and experimental group(s) was significant.

A conclusion is then drawn and stated as to whether the hypothesis was correct or not.

Next Steps…Scientists can then:

Publish their researchRe-test to examine if the results are

consistent.Revise or change their hypothesis and

experiment again.Look for sources of error in their process.

What if an Experiment Can’t be Run? Sometimes due to moral, ethical, practical,

or financial constraints an experiment cannot be run.

We would then use the process of correlation- which should be a reliable association between two or more events.

However correlation does not prove causation. Since we are not isolating one variable, we can’t be sure that one causes the other.

Let’s look at some good and bad correlations…

The Good, the Bad, and the Ugly People who eat McDonald’s every day are

more likely to be obese. Backed up by scientific data that people who

eat McDonald’s every day have more health problems than those who don’t.

Bad A soccer team that practices 30 minutes more a

day than a rival has a better record.

Ugly http://

www.tylervigen.com/view_correlation?id=359 http://

www.tylervigen.com/view_correlation?id=7

Scientific Habits Curiosity Skepticism Openness to New Ideas Intellectual Honesty Imagination and Creativity

What is a Scientific Theory or Law? A scientific theory is when a particular

hypothesis has many experiments and observations supporting it over time It is an explanation of natural phenomena that

has a large body of scientific evidence to support it.

A scientific law is when a certain explanation has accrued enough scientific evidence that it is assumed to be true.

In science however, we can never absolutely prove something; all we can do is fail to disprove it and refine it.

Types of Information In science we need to be able to classify

observations, results, and other information into types of information.

There are two main types of information: Quantitative Qualitative

Science and Society Science and the results of scientific

research are never inherently good or bad. It is how they are used or applied that is judged by the ethical values or moral values of a society.

Think of nuclear power: Nuclear bombs can cause much damage and

devastation. Nuclear power plants currently supply 48% of

New Jersey’s electricity as an alternative to oil or coal power plants.

Think of morphine: It can eliminate pain in those who have serious

medical problems It is highly addictive and can cause dependence

easily

Technology and Society

Technology is the application of scientific research to society’s needs and problems.

Technology itself is not good or bad; we judge it based on how it is used.

Statistics and Models

Statistics is the collection and classification of data in the form of numbers.

Models are representations of objects or systems.

Let’s explore how both are important to science and scientific research.

Terms to Know…

Statistical PopulationSample SizeMeanDistributionProbability

Risk Physical Models Graphical

Models Conceptual

Models Mathematical

Models

A Statistical Population is a group of similar things that someone wants to learn about.

Sample Size is how many individuals are in a sample or a statistical population. Fewer than twenty is not statistically

valid. The larger the sample size, the more

likely your results are significant.

Mean is the average.

Distribution is the arrangement of numbers of a statistical population. Example

Probability is the chance that something will happen. If a multiple choice question has 4 possible answers

there is a 25% probability of guessing the right answer if you have no idea. If you don’t answer it you have a 0% probability of getting it right.

Risk is the probability of an unwanted outcome. If you flip a coin to see who gets the last piece of

pizza. The risk of losing is 1 out of 2 or 50%.

Models

Models are representations of processes or systems. Physical Models are three-dimensional

models that one can touch. Graphical Models are a graphical

representation of data such as a map, star chart, or bar graph.

Conceptual Models are verbal, graphical, or pictoral explanations for how a process or system works.

Mathematical Models use mathematical equations to represent how a process or system works.

Choosing the Best Type of Model

How does the data need to be presented?

What kind of data do we have?What do we want to show?What will the model be used for?

A Decision-Making Model

A decision-making model is a conceptual model that provides a systematic process for making decisions…in other words we follow a set of steps to help us make a decision.

We need to examine our individual and group values to see what is important to us.

The Steps

1. We gather information.2. We consider our values.3. We explore the consequences

or effects of our decision.4. We make a decision.

Let’s look at an example…Should Sussex Tech build a new pool?

1. Gather information. What would we use it for? How much would it cost? Where would it go? What do we do with the old

pool? How much material is needed? Can the community use it?

Should Sussex Tech build a new pool?2. Consider Values Aesthetic-what is beautiful or pleasing Economic-use of money or creation/loss of jobs Environmental-the protection of natural resources Educational-the sharing or gaining of knowledge Ethical/Moral-right or wrong Health-is it good for humans Recreational-does it provide fun Scientific-increasing our understanding of the natural

world Social/Cultural-the maintenance of our communities,

values, and traditions

Should Sussex Tech build a new pool?

3. Explore the consequences and effects

Should Sussex Tech build a new pool?

4. Make a DecisionWho makes it?Who makes sure that the process is carried out as you want it to be?

Now an Environmental Example

Should wolves be re-introduced into NJ, NY, and Pennsylvania?

1. Gather information

2. Consider Values

3. Explore Consequences

4. Make a Decision

Decision-Making Model Assignment

Please look at your handout on one of the following topics:The Keystone XL PipelineFrackingLegalization of Deer Hunting in New JerseyBuilding New Dunes on the Jersey ShoreFlood Protection System in Venice, ItalyBuilding the Bell Bend Nuclear Power Plant in

Salem Township, PA