Traits of Well Designed Experiment Ms. Stocker
5 Characteristics of a Well Designed Experiment Controlled Multiple Trials Large Samples Random Samples Good Records/Repeatable
Controlled Only one variable is manipulated by the experimenter Independent Variable Ex) Amount of Water Dependent Variable Ex) Height of plant
Multiple Trials/Large Sample Do the experiment more than once Don’t just do a single test and say it proves your results Have a lot of individuals to test Have multiple subject per test condition Ex) 50 plants get fertilizer and 50 do not get fertilizer
Random Sample Make sure your test subjects are representative of the population you want to apply your results towards You cannot test DAE kids then say the results apply to the whole county/state!
Good Records Your experiment must be repeatable! Write detailed directions how to conduct your experiment Record all of your data accurately The Village idiot must be able to get the same results you did!
Loose Ends Experimental Group Control Group Constants Receives the experimental version of the independent variable Ex) plant with fertilizer Control Group Receives the normal version of the independent variable Ex) plant with no fertilizer This group is used for comparison! Constants Any variables that could change the outcome of the experiment Ex) temperature, amount of water, type of soil, length of sunlight exposure, amount of room to grow, etc…..