In layperson terms your questions are too hard for the group you are testing.
Floor effect stats.
This is even more of a problem with multiple choice tests.
This could be hiding a possible effect of the independent variable the variable being manipulated.
For example the distribution of scores on an ability test will be skewed by a floor effect if the test is much too difficult for many of the respondents and many of them obtain zero scores.
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.
A floor effect is when most of your subjects score near the bottom.
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.
Usually this is because of inherent weaknesses in the measuring devices or the measurement scoring system.
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.
Psychology definition of floor effect.
This lower limit is known as the floor.
There is an obvious floor effect in my data.
Limited variability in the data gathered on one variable may reduce the power of statistics on correlations between that variable and another variable.
In research a floor effect aka basement effect is when measurements of the dependent variable the variable exposed to the independent variable and then measured result in very low scores on the measurement scale.
The lower limit which affects dependent variables is referred to as the floor and can badly skew a data distribution if not accounted for.
The inability of a test to measure or discriminate below a certain point usually because its items are too difficult.
Most of the participans achieved the lowest possible score which is only 74 sd from the mean score.
For example a measure that assesses caregiver depression may not be sensitive enough to assess low or intermittent levels of depression among caregivers.
Floor effects occur when a measure s lowest score is unable to assess a patient s level of ability.
Ceiling effects and floor effects both limit the range of data reported by the instrument reducing variability in the gathered data.