The Scientific Method Problem What is it How

The Scientific Method

Problem • What is it? • How do you come up with one? • What is the correct format for writing one in science?

Problem • What needs to be solved / figured out • includes background research, experience • Format: What is the Affect of __(IV)_ on __(DV)__? How does _____ Affect _____? • EXAMPLE: What is the affect of doing HW daily on my performance on the test?

Hypothesis • Definition • Format • Example Problem: What is the affect of doing HW daily on my performance on the test? Hypothesis?

Hypothesis • Statement that can be tested; educated prediction • If… then… because format Example: If I do my HW every day, then I am more likely to do well on the EOC because I’ve had more practice with the concepts.

Experiment • How do you design a proper experiment?

Experiment • Testing a hypothesis, detailed procedure, – Steps begin with verbs, multiple trials, repeatable – Control vs. Experimental groups

Control Group • Purpose • Example Biology students are split into two groups. Group A does their homework every night. Group B never does their homework.

Control • Standard for comparison, • What you expect to happen under “normal” conditions 2 kinds • positive control – shows what the result will be if the experiment works • negative control – shows what the result will look like if nothing happens

Experimental Group • What is it? • Example Biology students are split into two groups. Group A does their homework every night. Group B never does their homework.

Experimental Group • You purposely change the IV in this group • If your DV changes as a result, then you know there’s a connection

Independent Variable (IV) • What is it? • Why it is necessary to test only 1? • Example

Independent Variable • Is manipulated (changed) on purpose “I can change the Independent variable!” • Often affects the dependent variable – Test only one IV at a time • If more than 1, which caused the results? Sample IV: whether the students do HW

Dependent Variable (DV) • What is it? • What does it depend on? • Example: Both groups of students take the biology EOC. 85% of group A pass while only 23% of group B passed.

Dependent Variable (DV) • • What changes as a result of the IV (Results) Outcome of experiment What you measure over time Depends on the IV • Both groups of students take the biology EOC. 85% of group A pass while only 23% of group B passed. DV is performance on the test.

Connections 1. In a problem: 2. In a hypothesis: 3. On a graph:

Connections 1. In a Problem Q: What is the affect of IV on the DV? 2. In a hyp: If IV then DV 3. On a graph: The IV is on the X AXIS, the DV is on the Y AXIS.

Constants • What are they? • Why are they necessary to think about? • Example Biology students are split into two groups. Group A does their homework every night. Group B never does their homework. What should be kept constant?

Constants • Remain the same in ALL groups including control – allows you to be sure your results are due to the IV you’re testing • Example: – Everyone learns the same material in class – Everyone has the same teacher – Everyone gets a good night sleep before the test – etc

A zoologist wants to know if feeding mice a vitamin supplement will make them grow larger. She feeds five mice their regular food, and she feeds five other mice food with vitamins. She measures the weight of the mice at the start and end of the experiment. • hypothesis: • independent variable: • control: • 3 constants:

Analysis • • Averages of data Statistics Graphs Trends • 85% of group A pass while only 23% of group B passed. • Appropriate presentation of data?

Conclusions • Contents - What should be included? • Example

Conclusions • Compare results to hypothesis • Do the data support it? • Scientific explanation • Example: The results do support the hypothesis that… This is shown by… This occurred b/c…