Logarithmic scale


Also found in: Dictionary, Thesaurus, Medical, Encyclopedia, Wikipedia.

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 ?
The result shows a near-linear dependence of RMS with the measurement length scale on a double logarithmic scale.
As background to the log-log plots (Figure 3), Armitage and Doll (12,13) in 1954 demonstrated that the age-specific incidence rates of certain epithelial cancers have a linear slope when plotted against the age of diagnosis on logarithmic scales.
01 T to allow them to be plotted on the logarithmic scale.
Even though the logarithm of time transfor mation in an RTD study was mentioned by Todd and Irving [11], the median residence time was considered instead of the mean residence time when tracer concentration was plotted against the time in logarithmic scale.
As a final example, we consider a tempo function in which acceleration is a constant with respect to a logarithmic scale of tempo.
On a logarithmic scale, this gives straight lines with a slope of about 0.
Three things become clear from this refined analysis: (1) computing progress has been tightly coupled around a trend line; (2) this makes predictions of future technologies reasonable by extrapolation; and (3) there's been an interesting acceleration over the last 30 years, even on this logarithmic scale.
13] With arms imports calculated on a logarithmic scale to correct for skewness, [14] the LOWESS curves in both the graphs reveal that in countries that import no more than $20 million (in constant 1991 dollars) [15] of arms, there is a negative relationship between arms imports and conditions of democracy.
We have examined this problem previously [2], and shown that scientific creativity exhibits a logarithmic scale rather than a linear one, thus giving rise to different distinct levels.
Anecdotes cited in support of the "new economy" suggest that many economists have been looking at the wrong scale; they have been looking at the number of new things on an arithmetic scale, rather than the rate on a logarithmic scale.