Scientific Methodology One Goal of Science is to provide natural explanations for events in the natural world Then, use those explanations to understand patterns in nature and make predictions about natural events

1.Observations: the act of noticing and describing events in a careful, orderly way; * Uses the senses * Can be Qualitative (descriptions) ie: The classroom floor is shiny or Quantitative (numbers) ie: There are 23 students in the classroom - these observations lead to Questions or PROBLEMS which need to be solved

2. Hypothesis: possible explanation for observations or questions that can be tested Written as “if IV, then DV, because…” 3. Controlled Experiment (test) - only ONE variable is changed - control group: exposed to the same conditions as experimental group EXCEPT for one Independent Variable (IV)

4. Collect/ Record/ Analyze Data - - Qualitative Data (descriptions) and Quantitative Data (numbers; measurements) * Data can be collected and organized into a Data Table then represented using Graphs Table and graph titles: The DV as a function of the IV

5. Conclusions - experimental data is used as Evidence to support, refute, or revise the hypothesis. * Inferences - an explanation or interpretation of your observations or data. - they SHOULD be reasonable or logical and based upon your data

For example, suppose you are on a photo safari in Africa. In a region bordering some small farms, you see some domestic cattle sharing space with some wild antelope. Some people in your group make the following observations and inferences. Observation: The cattle and the antelope are standing quietly together. Inference 1: The cattle and antelope do not attack each other. Inference 2: None of the animals in this region attack each other. Observation: Some of the cattle are eating grass. Inference 3: The grass is food for the cattle and antelope. Inference 4: Most of the grass in this area is eaten by the cattle.

Predicting - –Making an inference about a future event based upon current evidence or past experience. Look for patterns Can turn out not to be true Are usually tested

Identifying Variables Every experiment involves several variables - factors which can change

Independent Variables Also called “Manipulated variables” or IV This is the variable you PURPOSELY change and test ie - the temperature of the room

Dependent Variable Also called - “Responding Variable” or DV The factor that MAY CHANGE as a result of the Independent Variable ie: how fast plants grow in response to the temperature change.

Controlling Variables Keeping all conditions the same EXCEPT for the Independent Variable (IV) Ie: size of the container, type of soil, amount of water, amount of light, use of fertilizers, same kind of plants When all variables are controlled, you can then conclude that the differences in your results are due to the changes in the Independent Variable (IV)