Term | Definition |
---|---|

Variable | any entity that can take on different values |

Measurement | is the process of assigning numerals to objects to represent quantities of characteristics according to certain rules |

Dependent Variable | is what you measure in the experiment and what is affected during the experiment. The dependent variable responds to the independent variable. It is called dependent because it "depends" on the independent variable. |

Independent Variable | a variable that stands alone and isn't changed by the other variables being measured |

Control Variable | is the one element that is not changed throughout an experiment, because its unchanging state allows the relationship between the other variables being tested to be better understood. |

Extraneous Variable | are undesirable variables that influence the relationship between the variables that an experimenter is examining. |

Moderator Variable | commonly denoted as just M, is a third variable that affects the strength of the relationship between a dependent and independent variable In correlation, a moderator is a third variable that affects the correlation of two variables. |

Treatment Variable | Synonym for independent variable |

Factorial Design | When you have multiple independent variables in a single study |

Confounding | s an extraneous variable whose presence affects the variables being studied so that the results you get do not reflect the actual relationship between the variables under investigation. |

Null Hypothesis | the hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error. |

Chance | a possibility of something happening. |

Research Hypothesis | is the statement created by researchers when they speculate upon the outcome of a research or experiment. |

Directional Research Hypothesis | is specific, in that the experimenter predicts, not only that a specific relationship will exist, but, further, the direction of that relationship. |

Non-directional Research Hypothesis | predicts that the independent variable will have an effect on the dependent variable, but the direction of the effect is not specified. |

Population | a well-defined collection of individuals or objects known to have similar characteristics |

Sample | a subset used to represent the entire group as a whole |

Statistical Significance | means that a result from testing or experimenting is not likely to occur randomly or by chance, but is instead likely to be attributable to a specific cause. |

Significance Level | the probability of rejecting the null hypothesis given that it is true |

Qualitative Research | used to gain an understanding of underlying reasons, opinions, and motivations |

Quantitative Research | used to quantify the problem by way of generating numerical data or data that can be transformed into useable statistics |

Informed Consent | a legal procedure to ensure that a patient, client and research participants are aware of all the potential risks and costs involved in a treatment or procedure |

Debriefing | is a short interview that takes place between researchers and research participants immediately following their participation in an experiment. |

Random Assignment | the use of chance procedures in experiments to ensure that each participant has the same opportunity to be assigned to any given group |

Double-Blind Study | is one in which neither the participants nor the experimenters know who is receiving a particular treatment. This procedure is utilized to prevent bias in research results. |

Placebo Effect | a beneficial effect, produced by a placebo drug or treatment, that cannot be attributed to the properties of the placebo itself, and must therefore be due to the patient's belief in that treatment. |

Correlation Coefficient | a number between ?1 and +1 calculated so as to represent the linear dependence of two variables or sets of data |