Scientific Method
The Steps:
Make observations
Develop a question
Formulate a hypothesis
Conduct a controlled experiment
Draw Conclusions
Share Results
Two Scientific Approaches:
Hypothesis-based - Manipulate and see what happened (run an experiment). Explanatory variable- cause (what is being manipulated ) Response variable- Effect
Control and Treatment Group - The control group is an unchanged situation. The treatment group is the changed situation.
Experiments must have both groups.
Can have more than one treatment group.
Descriptive-based- Observe and record (doesn’t alter what occurs)
Data approaches: Quantitative vs. Qualitative
Quantitative (objective) - continuous numbers, only numbers.
Qualitative (subjective) - Words/ descriptions, categories.
Bias: can be reduced
Single-blind - The patient does NOT know what treatment they received, but the doctor does.
Double-blind - Both the patient and doctor do NOT know which is the placebo (fake) or real drug.
Sample size: Number of replicates in the study/experiment. More is better.
Can science prove things? NO. We only “support” or “fail to support” a hypothesis.
Fact vs Hypothesis vs Theory
Fact: An observation. Ex- the sky is blue
Hypothesis: Proposed explanation for an observation. Must be testable.
Theory: Explains a great many observations. Supported by evidence.
Scientific Theories
Universal Gravitational Theory
Evolution by Natural Selection
Earthquakes from Plate Tectonics
Climate change Buildup of Greenhouse Gasses
Scientific Paper
How to read them:
Title and authors
Abstract- summary of the whole paper.
Intro- background information on the study. Hypothesis and predictions.
Methods- details of how the study/experiment was set up.
Results- data, tables/graphs
Discussion- Conclusion
References- other’s research
Science vs Fraud vs Pseudoscience
Science: the pursuit of knowledge using the scientific method
Fraud: Deliberate lies
Pseudoscience: the belief or practice not based on science or fact.
Science:
Changes with new evidence
Follows evidence
Embraces criticism
Pseudoscience:
Fixed and unyielding ideas
Starts with conclusion
Hostile towards criticism
Graphs
Requirements: Title, labels, consistent axis increments, data types (quantitative or quantitative).
Bar Graph:
Comparing different groups
Starts y-axis at 0
Compares absolute value
Line Graph:
Comparing change (time)
Doesn’t always need a y-axis at 0
Time often on the x-axis
Pie Graph:
Comparing parts of a whole
Wedges need to represent the percentage