Definitions for "NULL HYPOTHESIS"
A tentative explanation which indicates that a chance distribution is operating; a contrast to the null hypothesis.
In the ANOVA context, a statement that there is no difference among a set of true means.  In other statistical settings, the statement similarly refers to an absence of interesting differences.  Because observed means are estimates of the true values, statistical machinery is invoked to determine the validity of the hypothesis.  The fallibility of data implies that some incorrect decisions are inevitable.
The idea that the causes, effects, amounts, or changes in question (the study “variables”) are not really connected to each other at all. This hypothesis is the opposite of the research hypothesis. pen-ended questions – Questions which let people answer in their own words instead of having to choose from set answers like “a” or “b” or “true” or “false.
a baseline or default explanation, against which other hypotheses can be measured
Keywords:  lane, steps