BASIC Microcomputing and Biostatistics

Modeling Growth and Mortality of Red Abalone (Haliotis Rufescens) in Northern California

“…The equation with n taking on negative values, which may be large from -1, -10, -100, ., -1 000 000 tending to N yields a family of quasi-sigmoidal Gompertz curves spaced at equidistant intervals from the origin with vertical inflection points from 8 to about 75 y. These impossibly long induction periods preceding growth is often compensated for by means of a negative additive parameter (Matsuishi et al 1995), Gompertz curves are not strictly sigmoidal; for example, the curve at n ¼ -100 000 first rises above f(L t ) ¼ 0, the Length axis, at 38 y and attains L N at about 70 y; but the vertical inflection point is at only 47 y, in contrast to the vertical inflection at 56 y that one would expect of a truly sigmoidal curve, for example, the cumulative Gaussian distribution (Rogers 1983). Adjusting the base of the Gompertz curve (rightmost curve in, Richards, Fig.…”

“…It is a three-parameter model (Rogers 1983) for which the parameters are well defined including maximum growth (A ¼ 22.0 mm y -1 ), size at maximum growth (m ¼ 62.0 mm), and standard deviation (s ¼ 70.2 mm) of the distribution of maximum growth versus size. The initial annual growth rate is DL ¼ 15.0 mm y -1 .…”

Iterative Methods

“…as the equation of our straight line fit. Further treatment, which we shall not go into here, involves finding the t value for each parameter and establishing the confidence limits at some confidence level, for example, 90%, 95%, or 99% (Rogers, 1983). These limits are given in block 2 of the TableCurve output.…”

“…Student's t statistics (Rogers, 1983) follow in the usual way as do the 95% confidence limits on the computed slopes, fð4:32 AE 0:12Þ Â 10 À3 ; ð2:72 AE 0:77ÞÂ 10 À3 g at 440 nm and fð3:85 AE 2:7Þ Â 10 À4 ; ð4:29 AE 0:17Þ Â 10 À2 g at 525 nm. These are not the same as the standard deviations due to the t statistic.…”

“…MOBAS was written by the author (Rogers, 1983) in BASIC to illustrate matrix inversion in molecular orbital calculations. It is modeled after a program in FORTRAN II given by Dickson (Dickson, 1968).…”