Underestimate: In contrast to an overestimate, an underestimate occurs when an estimated value falls below its true or actual value.
Sampling Bias: Sampling bias refers to a systematic error that occurs during sampling where certain individuals or groups are more likely to be included than others. This can lead to overestimation or underestimation of certain characteristics.
Nonresponse Bias: Nonresponse bias occurs when individuals chosen for a study do not participate or respond fully, leading to potential inaccuracies in the results. This can also cause overestimates or underestimates.