bio 121: set 1

intro to bio/graphing

Independent Variable

(also known as the predictor or explanatory variable): A variable whose value does not depend on the value of another variable. Common examples include the treatment groups in an experimental study or time.

Dependent Variable

(also known as the response variable): A measured quantity whose value depends on the value of another variable.

Discrete Variable

A quantity that can only take certain, discrete values.

Continuous Variable

A quantity that can take a continuous range of values.

Scatterplot

A type of graph where individual datapoints from two continuous variables are plotted to assess whether the variables are correlated in any way.

Histogram

A type of graph where a range of possible values is plotted along the x-axis and the frequency of datapoints in each interval in the range is plotted on the y-axis.

Hypothesis

A proposed explanation for something that researchers have observed.

Prediction

A statement of an outcome that should occur if a hypothesis is correct.

null hypothesis

A hypothesis that represents the "not" or "no-effect" contrast to the hypothesis being tested.

treatment (experimental ) group

A group that experiences experimental conditions that conform to the mechanism proposed in the hypothesis.

Control Group

A comparison group that represents the normal or no-treatment condition to contrast with groups that experience experimental manipulation. 

Controlled conditions

Aspects of an experimental design that are used in both control and experimental treatments to eliminate bias among treatments and reduce influence from confounding factors.

outcome conditions

The variable that is measured in an experimental or observational study. It represents a quantity that is relevant to the hypothesis being tested.