Logarithmic scale

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Logarithmic Scale

A scale where the same percentage of change between two data points (with respect to two other data points) may represent different, raw amounts of change. For example, a logarithmic scale of a stock may show a graph where a change from $4 per share to $8 per share is the same distance as a change from $40 per share to $80.

Logarithmic scale.

On a logarithmic scale or graph, comparable percentage changes in the value of an investment, index, or average appear to be similar. However, the actual underlying change in value may be significantly different.

For example, a stock whose price increases during the year from $25 to $50 a share has the same percentage change as a stock whose price increases from $100 to $200 a share.

On a logarithmic scale, it's irrelevant that the dollar value of the second stock is four times the value of the first.

Similarly, the percentage change in the Dow Jones Industrial Average (DJIA) as it rose from 1,000 to 2,000 is comparable to the percentage change when it moved from 4,000 to 8,000.

References in periodicals archive ?
Within-site variation in counts (vari- ance, log scale) 0.04
Rate of change of inter-observer mean (log scale) 0.05
Assuming that the prices paid for F2 and F3 yellow poplar logs were $150/MBF and $140/MBF in Doyle log scale, the purchase prices for red oak logs were $300/MBF for F2 grade and $280/MBF for F3 grade, and the average operating cost ranged from $160/MBF for circular sawmills to $200/MBF for band sawmills, a value ratio was computed based on species, diameter classes, and sawmills (Fig.
of thousand bd ft of Species (in.) logs lumber tally ($/MBF) Red oak 10 22 485 11 16 422 12 30 420 13 26 446 14 27 454 15 29 469 Yellow poplar 10 7 341 11 9 304 12 20 301 13 18 334 14 12 326 15 14 357 Dollars per Dollars per hundred cu ft of thousand bd ft of Species net log scale ($/CCF) net log scale ($/MBFLS) Red oak 320 782 264 639 267 620 286 584 291 607 304 557 Yellow poplar 240 518 206 452 205 442 228 474 225 421 254 467 (a) SED = small-end diameter (inside bark); bd ft = board feet; cu ft = cubic feet.
To calculate LO, the volume of lumber produced (expressed in board feet lumber tally) in excess of the Scribner log scale volume processed was divided by the Scribner volume of logs and expressed as a percentage.
Measures of the volume of lumber produced per unit of log input can be influenced by a range of factors in addition to log scale. These factors include technology, log size, lumber size, lumber grade, and market conditions for lumber and residue--particularly coarse residue.
For each study sample log, absolute sweep, small-end diameter, and log length were used to determine sweep log scale deductions.
Assuming that the average log size at this sawmill is 100 BF (International 1/4inch log scale) and using the overrun statistics presented in Figure 4, then approximately 106 BF of lumber (1.058 x 100 BF) would be recovered from one highly elliptical log in comparison to the estimated 117 BF (1.169 x 100 BF) of lumber yielded from one low-ellipticity shaped log.
For hardwood logs with average sweep of 3.3 inches and greater (12-foot log length basis), and log scale deduction of over 15 percent, lumber yield can be 10 to 12 percent higher when curve sawing.
Forty-eight percent of log scale volume (scaling yield) was converted into clear dimension parts.
Figure 1 plots the amplitudes of ERGs recorded from dark-adapted Tachypleus and Limulus eyes on log scales as a function of log light intensity.
Spelter (2004) and Fonseca (2005) provide additional information and references about Scribner and other log scales.