Exam 1 Prep: Data Collection, Measurement, and Analysis

Vocabulary flashcards covering basic terminology, measurement types, sampling methods, descriptive statistics, and randomness from the Exam 1 Prep lecture notes.

Observations

The act of looking at one unit.

Populations

The demographic that is being studied.

Sample

Taking a piece of the population but not all of it, measured so as to reflect results to the entire population.

Inference

The process of making statistical conclusions about data.

External Validity

The ability to extend the results from a sample to draw important conclusions about an entire population.

Cherry-Picking

Purposely sampling data in a way to get a desired result.

Aggregated Data

A type of summary statistic that can be misleading because it can mask variation in the data.

Sample Selection Problem

When an analysis is ran on less than the entire data set.

Bivariate Relationship

A relationship between two variables that does not prove that one thing caused the other.

WEIRD Societies

Western, Educated, Industrialized, Rich, and Democratic societies that influence current data and are not reflective of humanity as a whole.

Big Data

Data that is too big to process without the use of sophisticated software and computing.

Little Data

The small bits and bytes of data that is common.

Hidden Data

Data that may not be publicly known.

Anecdotes

Information based on individual stories and experiences that can be persuasive and memorable, but is not accurate data to rely on for reaching a conclusion.

Raw Numbers

A count of occurrence.

Percentage

A count of an occurrence divided by total possible occurrences.

Rate

The frequency of which an occurrence occurs, adjusted for the population.

Random Selection

A selection method ensuring every individual has an equal chance of being chosen, used to avoid intentional bias whilst remaining true to the representation of the sample.

Descriptive Statistics

A statistic that describes a group by addressing a group of variables.

Mean

The most common type of average computed, calculated as the sum of all values in a group divided by the number of values in that group.

Median

The midpoint in a set of scores, representing the point at which one half or $50\%$ of the scores fall below or above that marker.

Outliers

Data points that deviate or do not follow the trend, which usually skew the trend.

Randomness (in Data)

The condition where units in a population have the same likelihood of being selected within a sample.

Statistical Significance

The percentage of which randomness and trends are determined; in the social sciences, a level of $p > 0.5$ is stated as needed to show an outcome is likely not due to chance.

Regression to the Mean

A phenomenon where extreme outcomes are followed by less extreme ones due to randomness, causing unusual streaks to revert toward averages.