Steps of scientific methods

How to design an experiment Divide samples in 2 groups Control and Experimental group Lets talk about the hand lotion experiment What is a control group? That does NOT get the treatment… In science we call it the variable HAND LOTION What is the experimental group? That gets the treatment… Or the variable Also called the independent variable

How is control group different from the experimental group? __________doesn’t get treated (no Mr V) and _________group gets treated Are they different in any other respect? NOOOOOO…. Except for the TREATMENT, everything else has to be the same… all other variables have to be controlled Called the controlled variables

What else do you do while doing the experiment? Record data/result by making observations What is the best way to record data? In words or in the form of a table? ___________ Organize it in the form of a table… Easy to read and analyze (make sense by thinking) Even better, make a graph A picture is worth thousand words What do you with the graph? Interpret (find the meaning) it to draw a conclusion

Let’s put all the steps together

How do you write the conclusion? Cheat from the hypothesis… steal words from the hypothesis

What is dependent variable? The observation of the experiment Hand lotion experiment…what are you observing during the experiment? Quality of skin

How to make experiment VALID? Repeat 3 times Take large sample number Results should be repeatable/reproducible

Do Now: What is wrong with the following experiment? Lets say you run a company that is working on finding a drug to control migraine. Your drug is called ‘drug X.’ To test it, you take 2 people and give them the drug. It seems to work and you claim that your drug works.

Identify the problem and the hypothesis of the following reading

What is the conclusion from the reading?

Lets now figure out how to write the conclusion…