The lower limit which affects dependent variables is referred to as the floor and can badly skew a data distribution if not accounted for.
Floor effect stats.
In statistics a floor effect also known as a basement effect arises when a data gathering instrument has a lower limit to the data values it can reliably specify.
Limited variability in the data gathered on one variable may reduce the power of statistics on correlations between that variable and another variable.
There is very little variance because the floor of your test is too high.
There is an obvious floor effect in my data.
In layperson terms your questions are too hard for the group you are testing.
Floor effects occur when a measure s lowest score is unable to assess a patient s level of ability.
For example a measure that assesses caregiver depression may not be sensitive enough to assess low or intermittent levels of depression among caregivers.
The floor effect is what happens when there is an artificial lower limit below which data levels can t be measured.
This lower limit is known as the floor.
Ceiling effects and floor effects both limit the range of data reported by the instrument reducing variability in the gathered data.
Usually this is because of inherent weaknesses in the measuring devices or the measurement scoring system.
Let s talk about floor and ceiling effects for a minute.
A floor effect is when most of your subjects score near the bottom.
Most of the participans achieved the lowest possible score which is only 74 sd from the mean score.
This is even more of a problem with multiple choice tests.
A floor effect occurs when a measure possesses a distinct lower limit for potential responses and a large concentration of participants score at or near this limit the opposite of a ceiling effect.
In statistics and measurement theory an artificial lower limit on the value that a variable can attain causing the distribution of scores to be skewed.
The inability of a test to measure or discriminate below a certain point usually because its items are too difficult.
Psychology definition of floor effect.