Table 1.

Data for firefly study.

x1	x2	x3	y
1	26	21.1	45
1	35	23.9	40
1	40	17.8	58
1	41	22.0	50
1	45	22.3	31
1	55	23.3	52
I	55	20.5	54
1	56	25.5	38
1	70	21.7	40
1.	75	26.7	28
1	79	25.0	38
1	87	24.4	36
1	100	22.3	36
1	100	25.5	46
1	110	26.7	40
1	130	25.5	31
1	140	26.7	40

Definition of Variables

y=time of First flash (number of minutes after 6:30 p.m.)

x₂=light intensity (in metercandles, mc)

x₃=temperature (°C)