Table 2.

Time estimation of four human adults in the absence of known time cues

		EH (M)		MS (M)		TS (M)		JL (F)
Procedure (interval)	Index evaluated	N of obs (N of days)	R (± SD)	N of obs (N of days)	R (± SD)	N of obs (N of days)	R (± SD)	N of obs (N of days)	R (± SD)	Isolation
“Intuitive” (empty)	$\text{R}*=\frac{\text{S\hspace{0.17em}months}}{\text{E\hspace{0.17em}months}}$			2 (59)	0.58	2 (121)	0.54	2 (87)	0.84
	$\text{R}=\frac{\text{S\hspace{0.17em}hours}}{\text{E\hspace{0.17em}hours}}$	108 (11)	1.01 (± 0.17)	231 (59)	0.56 (± 0.28)	536 (125)	0.66 (± 0.31)	294 (88)	0.45 (± 0.25)	Yes
Rational (filled, ie, counting from 1 to 120)	$\text{R}=\frac{\text{S\hspace{0.17em}seconds}}{\text{E\hspace{0.17em}seconds}}$			168 (59)	0.67 (± 0.12)	310 (125)	0.92 (± 0.09)	175 (88)	0.62 (± 0.12)
						161 (31)	0.96 (± 0.08)	196 (31)	0.88 (±0.09)	No

^*Notes: ${}^{*}\text{R}=\frac{\text{S(Subject)\hspace{0.17em}time}}{\text{E(Environment)\hspace{0.17em}time}}$; these ratios are in italics; they represent means, except for those in first row of table; Means and standard deviations in table refer to data previously “clipped” to mean ± 3 SD; iterative clippings until 4 decimal places remain the same.

Abbreviations: S = subjective; E = environmental.