Chapter 1: Measurement, Statistics, and Research Flashcards

Vocabulary flashcards covering measurement concepts, levels of data, research design, hypothesis testing, validity, and statistical inference from Chapter 1.

Measurement

The process of comparing a value to a standard.

Data

The result of measurement.

Statistics

A mathematical technique by which data are organized, treated, and presented for interpretation and evaluation.

Reliability

Reproducibility and consistency.

Validity

Soundness or the appropriateness of a test in measuring what it is designed to measure.

Variable

A characteristic of a person, place, or object that can assume more than one value.

Constant

A characteristic that can assume only one value.

Continuous variable

A variable that theoretically can assume any value, limited only by the precision of the measurement instrument.

Discrete variable

A variable that is limited to certain numbers, usually whole numbers.

Nominal scale

A classification of data into mutually exclusive categories where the assigned number does not indicate an amount.

Ordinal scale

A classification of data that gives quantitative order to variables, but does not indicate how much better one score is than another.

Interval scale

A classification of data that has equal units or intervals of measurement between scale divisions, but has no absolute zero point.

Ratio scale

A classification of data based on order, with equal distance between scale points, that uses zero to represent the absence of value.

Research

A technique for solving problems or gaining new information through a systematic investigation designed to develop or contribute to generalizable knowledge.

Observational Research

Research designed to describe events or conditions that the researcher does not actively manipulate.

Experimental Research

A research process that involves manipulating and controlling events or variables to answer a research question.

Hypothesis

A logical assumption based on prior research or known facts that can be tested.

Research Hypothesis

The hypothesis that prompts the research (also referred to as the alternate hypothesis, $H_1$ or $H_A$), which usually predicts relationships or differences between or among groups.

Null Hypothesis

The hypothesis ($H_0$) that predicts no relationship or no difference between groups.

Independent variable

The variable manipulated or controlled by the researcher in an experimental study, or the predictor variable in an observational study.

Dependent variable

The variable that is measured in an experimental study, or the criterion variable in an observational study.

Internal Validity

A measure of the control within an experiment to ascertain that the results are due to the treatment that was applied.

External validity

The ability to generalize the results of an experiment to the population from which the samples were drawn.

Population

Any group of persons, places, or objects that have at least one common characteristic.

Sample

A subset of a population.

Random Sample

A sampling method in which each member of the population has an equal opportunity of being selected into the sample.

Stratified Sample

A sampling method in which the population is divided into subcategories (strata) and sampled from each stratum.

Bias

Extraneous factors that influence the sample to make it unrepresentative of the population.

Parameter

A characteristic of a population.

Statistic

A characteristic of a sample used to estimate the value of a population parameter.

Theory

A belief regarding a concept or a series of related concepts that generates testable and falsifiable hypotheses.