Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size Small Size show me how

Normal Size Small Size show me how

# MrsVanDyke Chapter 2

### Research Methods

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

Scientific Method | A five-step process for empirical investigation of a hypothesis under conditions designed to control biases and subjective judgments |

Empirical Investigation | An approach to research that relies on sensory experience and observation as research data |

Theory | A testable explanation for a set of facts or observations |

Hypothesis | A statement predicting the outcome of a scientific study; a statement describing the relationship among variables in a study |

Operational Definitions | Specific descriptions of concepts involving the conditions of a scientific study; stated in terms of how concepts are to be measured or what operations are being employed to produce them |

Independent Variable (IV) | A stimulus condition so named because the experimenter changes it independently of all the other carefully controlled experimental conditions |

Random Presentation | A process by which chance alone determines the order in which the stimulus is presented |

Data | Pieces of information, especially information gathered by a researcher to be used in testing a hypothesis |

Dependent Variable (DV) | The measured outcome of a study; the responses of the subjects in a study |

Replicate | doing a study over to see whether the same results are obtained |

Experiment | A kind of research in which the researcher controls all the conditions and directly manipulates the conditions, including the independent variable |

Confounding Variables (Extraneous Variables) | Variables that have an unwanted influence on the outcome of an experiement |

Controls | Constraints that the experimenter places on the experiment to ensure that each subject has the exact same conditions |

Random Assignment | Each subject of the sample has an equal likelihood of being chosen for the experimental group of an experiment |

Ex Post Facto | Research in which we choose subjects based on a pre-existing condition |

Correlational Study | A type of research that is mainly statistical in nature |

Survey | A quasi-experimental method in which questions are asked to subjects (questions should not be skewed or biased toward a specific answer) |

Naturalistic Observation | A research method in which subjects are observed in their natural environment |

Longitudinal Study | A type of study in which one group of subjects is followed and observed for an extended period of time |

Cross-Sectional Study | A study in which a representative cross section of the population is tested or surveyed at one specific time |

Cohort-Sequential Study | A research method in which a cross section of the population is chosen and then each cohort is followed for a short perid of time |

Personal Bias | The researcher allowing personal beliefs to affect the outcome of a study |

Expectancy Bias | The researcher allowing his or her expectations to affect the outcome of a study |

Double-Blind Study | An experimental procedure in which both researchers and participants are uninformed about the nature of the independent variable being administered |

Institutional Review Board (IRB) | A committee at each institution where research is conducted to review every experiment for ethics and methodology |

Institutional Animal Care and Use Committee (IACUC) | A committee at each institution where research is conducted to review every experiment involving animals for ethics and methodology |

Frequency Distribution | A summary chart, showing how frequently each of the various scores in a set of data occurs |

Histogram | A bar graph depicting a frequency distribution. Height of bars indicates the frequency of a group of scores |

Descriptive Statistics | Statistical procedures used to describe characteristics and responses of groups of subjects |

Mean | Measure of central tendency most often used to describe a set of data. Calculated by adding all the scores and dividing by the number of scores |

Median | Measure of central tendency for a distribution, represented by the score that separates the upper half of the scores in a distribution from the lower half |

Mode | Measure of central tendency for a distribution, represented by the score that occurs more often than any other |

Range | The simplest measure of variability, represented by the difference between the highest and the lowest values in a frequency distribution |

Standard Deviation (SD) | Measure of variability that indicates the average difference between the scores and their mean |

Normal Distribution | A bell curve, describing the spread of a characteristic throughout a population |

Correlation | Relationship between variables, in which changes in one variable are reflected in changes in the other variable |

Correlation Coefficient | A number between -1 and +1 expressing the degree of relationship between two variables |

Inferential Statistics | Statistical techniques used to assess whether the results of a study are reliable or whether they might be simply the result of chance |

Random Sample | A sample group of subjects selected by chance |

Representative Sample | A sample obtained in such a way that it reflects the distribution of important variables in the larger population in which the researchers are interested; i.e., age, income level, ethnicity, etc... |

Significant Difference | Psychologists accept a difference between the groups as "real", or significant when the probability that it might be due to an atypical sample drawn by chance is less than 5 in 100 (indicated by the notation p<0.05) |

Created by:
MrsVanDyke