Sample size bias in retrospective estimates of average duration

Abstract

People often estimate the average duration of several events (e.g., on average, how long does it take to drive from one's home to his or her office). While there is a great deal of research investigating estimates of duration for a single event, few studies have examined estimates when people must average across numerous stimuli or events. The current studies were designed to fill this gap by examining how people's estimates of average duration were influenced by the number of stimuli being averaged (i.e., the sample size). Based on research investigating the sample size bias, we predicted that participants' judgments of average duration would increase as the sample size increased. Across four studies, we demonstrated a sample size bias for estimates of average duration with different judgment types (numeric estimates and comparisons), study designs (between and within-subjects), and paradigms (observing images and performing tasks). The results are consistent with the more general notion that psychological representations of magnitudes in one dimension (e.g., quantity) can influence representations of magnitudes in another dimension (e.g., duration).

Factors Associated with Successful Response to Balloon Decompressive Adhesiolysis Neuroplasty in Patients with Chronic Lumbar Foraminal Stenosis

“…In the present study, multivariate logistic regression analysis revealed mild grade foraminal stenosis in lumbar MRI to be an independent factor positively associated with successful responses to decompressive adhesiolysis by using inflatable balloon catheter, which had not been revealed in previous studies. This discrepancy may be regarded as a limitation of a small-sample-size study [18] or a study of patients with mixed diagnoses (blended etiology of central type stenosis and foraminal type stenosis). A moderate or severe grade of lumbar foraminal stenosis suggests a more progressed state than mild stenosis and may be deemed more difficult to manage.…”

Judgments of frequency and duration: One or two underlying dimensions?

“…Several researchers (Bonanno, 1996;Hintzman, 2004;Williams & Durso, 1986;Zhao & Turk-Browne, 2011) studied only judgments of frequency and not judgments of duration, so we could not conduct the critical test. In one study (Smith et al, 2017) the independent variables had only two levels, so the effect size is not a normal correlation and our approach is not applicable.…”

“…In the laboratory, the exposure frequency and duration of stimuli can be varied orthogonally, and so accurate judgments of these attributes would be uncorrelated. But humans still produce correlated judgments: When they think an object has been presented often, they usually also judge it to have been presented for a long duration (e.g., Betsch et al, 2010;Hintzman, 1970;Hintzman et al, 1975;Smith et al, 2017;Winkler et al, 2015). Under certain conditions the reverse is also true: when an object has been presented for a long time, humans think it has been presented often (e.g., Betsch et al, 2010;Bonanno, 1996;Hintzman et al, 1975;Winkler et al, 2015;Zhao & Turk-Browne, 2011).…”

“…Half a century ago, Hintzman (1970) answered in the affirmative and concluded that judgments of frequency and duration must be based on two dimensions because they are affected differently by exposure frequency and duration (subsequently this was also expressed in Hintzman, 2011;Hintzman et al, 1975). But in the last decade new findings have accumulated and a unidimensional model has resurfaced again (e.g., Smith et al, 2017;Zhao & Turk-Browne, 2011). Specifically, Betsch et al (2010), as well as Winkler (2009) and Winkler et al (2015), have favored a unidimensional model.…”

“…Note that Smith et al (2017) discussed the unidimensional model only as one of several potential models. A bias in this context is an influence of the irrelevant independent variable on the judgment: frequency on judgment of duration or duration on judgment of frequency (as initially described in Betsch et al, 2010;Winkler et al, 2015).…”