Scientifically,a variable is an item, factor or condition that can be controlled orchanged. This report defines independent and dependent variableswhich are the basis for formulating a hypothesis for correlational,quasi-experimental and experimental studies. It also describes theirscale measurements and gives an example of a simple study usingSchmidt (1994).
Accordingto Marilyn, independent variables is the cause or influencing bywhich subgroups in the sample are distinguished in research. Theindependent variable in this study is humor. The researchermanipulated this variable to know if a sentence was humorous or not.The levels of measurement on humor or non-humor, are categories in noparticular order hence nominally scaled.
PeterF, (2016 p.77), states that dependent variables value changes as aresult of the movement in the independent variable. Therefore, it iswhat is measured in an experiment. In this study, the sentencesrecalled by the participants are the dependent variables. Eachsentence recalled increases the dependent variable by the same sizeand each sentence not recalled add up to zero, making the zero pointobsolete hence, the measurement uses a ratio scale.
Ina study investigating the effect of painting lessons in a mentalinstitution in which some patients were offered painting lessonswhile others were not, it showed that, those who received the lessonsrecovered faster than those who did not.
Theindependent variable in this study is the painting lessons since itis which the researchers manipulated and the dependent variable isthe patient’s ability to recover since it depended on whether thethey received the painting lessons or not.
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