PSY 002 Psychological Statistics Flashcards

Flashcards for reviewing Psychological Statistics Module 1.

Statistics

A set of mathematical procedures for organizing, summarizing, and interpreting information.

Population

The set of all the individuals of interest in a particular study; the totality of elements from which data is obtained.

Sample

A set of individuals selected from a population, intended to represent the population in a research study.

Parameter

A numerical value that describes a population.

Statistic

A numerical value that describes a sample; an estimate of a parameter.

Variable

A characteristic or condition that changes or has different values for different individuals.

Discrete Variable

Consists of separate, indivisible categories; no values exist between two neighboring categories (e.g., gender, nationality).

Continuous Variable

There are an infinite number of possible values that fall between any two observed values; divisible into an infinite number of fractional parts (e.g., weight, height).

Data (Datum)

Measurements or observations; facts or sets of information under study.

Metric Data

Data obtained by measurement (e.g., height, weight).

Enumeration Data

Data obtained by counting (e.g., number of students in a classroom).

Categorical Data

Data classified into groups or categories of responses (e.g., attitudes, perceptions).

Nominal Scale

Consists of a set of categories that have different names; labels and categorizes observations but does not make quantitative distinctions (e.g., gender, nationality).

Ordinal Scale

Consists of a set of categories organized in an ordered sequence; ranks observations in terms of size or magnitude (e.g., ranking of contestants).

Interval Scale

Has an arbitrary zero point; a value of zero does not indicate a total absence of the variable being measured (e.g., temperature, IQ scores).

Ratio Scale

Anchored by a zero point that represents a complete absence of the variable being measured; has a true zero point (e.g., age, height, weight).

Descriptive Statistics

Statistical procedures used to summarize, organize, and simplify data.

Inferential Statistics

Techniques that allow us to study samples and then make generalizations about the populations from which they were selected.

Sampling Error

The discrepancy or amount of error that exists between a sample statistic and the corresponding population parameter.

Non-Sampling Error

Error that arises in the data collection process as a result of factors other than taking a sample.

Sampling

The process of taking a sample from a population.

Sampling Technique

The procedure used to determine the individuals or members of the sample.

Probability Sampling

A sampling technique wherein each member of the population has an equal chance of being selected as a member of the sample.

Simple Random Sampling/Random Sampling

A technique of drawing a sample whereby each element of the population has an equal chance of being taken into the sample.

Systematic Sampling

A technique of choosing an element for every k elements of a population, where k = N/n, N is the population size and n is the sample size.

Stratified Sampling

A technique of dividing a population into groups (strata) and sampling is done in each stratum.

Cluster Sampling

A technique of taking a sample from groups, and all the elements in those groups chosen will form the sample.

Multi-Stage Sampling

Sampling in various stages until the desired sampling units are obtained.

Non-Probability Sampling

A sampling technique wherein members of the sample are drawn from the population based on the judgment of the researcher.

Convenience Sampling

Sampling used because of the convenience it offers to the researcher.

Purposive Sampling

A technique of choosing sampling units from a given population which have specific characteristics.

Snowball Sampling

A sampling method that researchers apply when the subjects are difficult to trace.

Quota Sampling

A technique of setting a sample size based on the nature of the data needed and taking the first sampling units that fulfill the required number or quota.