Statistics and Experimental Design Assessment - EC

Hypothesis

a tentative explanation that needs further investigation

Null Hypothesis

the hypothesis that there is no significant difference between specified populations, any observed difference being due to chance.

Alternative Hypothesis

The hypothesis that states that the results will be significantly different from one another.

Independent Variable

The experimental factor that is manipulated; the variable whose effect is being studied.

Dependent Variable

The outcome factor; the variable that may change in response to manipulations of the independent variable.

Experimental Group

the group in an experiment that receives the variable being tested

Constant Variable

A variable that is not changed

Positive Control Group

The group exposed to a treatment that is known to produce the measured/desired effect

Negative Control Group

Group that is not exposed to any treatment that is expected to cause a change in the desired/measured effect

Variance

how spread out the data is from the mean (average).

Standard Deviation

A measure of how spread out the data is from the mean.

Statistical Significance

how likely it is that an obtained result occurred by chance

Correlation

a mutual relationship or connection between two or more things

Key/Legend

Explains what each color, symbol, or pattern represents in the visualization

Mean/Average

The sum of the values in a set of numbers, divided by the number of values in the set.

Axis Break

A jump in either the x-axis or y-axis that skips over a wide range of values.

Equidistant

points are located the same distance apart or from a specific reference point

Line of Best Fit/Trendline

line or curve that best represents the data on a scatter plot; line or curve may pass through some, none, or all of the points

Line Graph

A graph that shows changes that occur over time

Bar Graph

A graph that shows comparisons among two or more items

Scatter Plot

A graph with points plotted to show a possible relationship between two sets of data.

Error Bar

Representation of uncertainty displayed on a graph.

Chi-square Test

A math problem that scientifically determines how big of a difference there must be to be considered a significant difference.