Vocab 1: Scientific Skills

Hypothesis (Alternative Hypothesis)

testable explanation for an observed phenomenon or scientific question, linking independent and dependent variables

Null Hypothesis

proposes that the independent variable has no statistical impact on the dependent variable, and any observed differences or data variations are due to random chance alone.

Prediction

logical statement about what will happen or what the outcome of an experiment will be if a hypothesis is correct

Independent Variable

variable that is deliberately changed or manipulated by the experimenter in an experiment

Dependent Variable

variable that is measured or observed in an experiment. Its value changes in response to manipulations of the independent variable

Experimental Group

group exposed to a specific modification of the independent variable. Its measurable response—the dependent variable—is recorded and compared against a control group to determine if the treatment has an effect

Control Group

controlled experiment, a group of subjects or conditions that is treated identically to the experimental group except for the one independent variable being tested; used as a baseline for comparison.

Constants (Controlled Variables)

All the factors that need to stay consistent when performing an experiment.

Standard Deviation

 measure of the amount of variation or dispersion in a set of data values. This indicates how tightly data points are clustered around the mean.

Standard Error

statistic that measures the accuracy with which a sample distribution represents a population by estimating the variability between sample means

Degrees of Freedom

the number of independent values or quantities that can vary in an analysis; for a sample variance or t-test

Chi Square Test (x² test)

non-parametric statistical analysis used to determine whether a set of observed categorical data differs significantly from a theoretical, expected distribution.

P Value

when compared to, determines the probability that the differences between observed and expected results happened purely by random chance.