Unit 1: The Scientific Method
2. making inferences & forming a hypothesis
-Inference is a logical interpretation based on what scientists already know. Inference leads to hypothesis. -hypothesis is a scientific explanation for a set of observations that can be tested in ways that support or reject it. -suggested (testable) answer to a well-defined scientific question, must also be falsifiable (AKA: could show that it is not true.)
What are hypotheses? What are alternative hypotheses?
-hypothesis is a scientific explanation for a set of observations that can be tested in ways that support or reject it. -suggested (testable) answer to a well-defined scientific question, must also be falsifiable (AKA: could show that it is not true.) -"If ___________, then ________ because ___________." -alternative says opposite of hypothesis
3.conducting controlled experiments
controlled experiment: when possible hypothesis should be tested by experiment where only one variable changes all others should be kept unchanged or be controlled.
experimental group
group of subjects that does receive the experimental variable Example: testing a new drug - this group WOULD receive the drug
control group
group that does not receive the experimental variable Example: testing a new drug- this group would NOT receive the drug
Sample size
how many times the test is repeated.
What are the steps to the scientific method?
making a observation, making inferences and forming a hypothesis, conducting controlled experiments, collecting and analyzing data, drawing conclusions.
double blind experiment
no one knows which group is which (researcher doesn't know either!)
blind experiment
people in experiment don't know which group they're in
experimental variable/independent variable
changes that occur in an experiment that are directly caused by the experimenter (you.)
4. Collecting and Analyzing data
scientists make detailed records of experimental observations, gathering info called data.
5. Drawing conclusions
scientists use experimental data as evidence to support, refute, or revise, the hypothesis being tested, and draw a valid conclusion.
1. making a observation
the act of noticing and describing events or processes in a careful orderly way.
What are some elements of a good scientific experiment?
-Careful design- results are valid & reliable. -It should be controlled. -You need to make sure that: you actually tested what you wanted to test your data is accurate your test is repeatable (with the same results).
What is the difference between quantitative data and qualitative data?
Qualitative: Deals with descriptions/ Data can be observed but not measured. EX: Colors, textures, smells, tastes, appearance, beauty, -Qualitative → Quality Quantitative:Deals with numbers/ Data which can be measured. EX: Length, height, area, volume, weight, speed, time, temperature, humidity, sound levels, cost, members, ages, etc. Quantitative → Quantity
What is a scientific theory? How do we develop a scientific theory? How is it different than a regular theory?
a scientific theory is a well-tested explanation that unifies a broad range of observations and hypotheses and enables the scientists to make accurate predictions about a new situations. -by running tests and making observations. -in real life when someone says a theory they mean something that's questionable. When scientists say they have a theory they mean they have tested evidence that supports a hypothesis.
controlled variable
all variables that could influence the dependent variable. Need to keep constant throughout the experiment
Dependent variable
the variable that changes in response to the independent variable (measurable!)
