Independent Variables
The relationship between the independent and dependent variable in an experiment in very important. An independent variable is a variable that the experimenter (or nature) manipulates in order to perform the experiment. A researcher will use this information to help understand the outcome of their experiment. For example, if a study is being done on whether men or women absorb vitamin D differently, the independent variable is the sex of the research participants.
Dependent Variables
The dependent variable are all the things that are dependent on the independent variable. Put differently, the dependent variable is what is affected by the independent variables. In the example of whether men or women would absorb vitamin D differently, the absorption rates would be the dependent variable. Making sure you have a good and clear understanding of the differences between independent and dependent variables will help you determine where the independent and dependent variables are in your own experiments.
Moldy Bread Experiment
In an experiment with moldy bread, a researcher might be trying to determine how much moisture it will take for a bread to go moldy. The independent variable would be how much water the researcher sprays on the bread. The amount of water is the independent variable because this is the variable the researcher controls. A researcher will decide how much water to add to find the results of his experiment. The dependent variable would be when the mold started to grow. This is a dependent variable because when the mold begins to grow depends on how much water or moisture is sprayed on the bread.
Another Moldy Bread Experiment
Another independent variable for an experiment involving moldy bread could be the type of bread used. Perhaps the researcher wants to find out what type of bread will got moldy the quickest. The researcher lays out pieces of sourdough bread, whole-wheat bread, white bread and rye bread to see which will grow mold first. The independent variable in this case would be the types of bread used since this is the variable the researcher changes to and controls in order to determine the experiments outcome.