The yellow and red lines represent one and two standard deviations from the mean ratio, respectively.
Original issues were less volatile, as measured by standard deviations of returns (3.52% versus 4.26%).
As the general population improves, standard deviations shrink and outliers move closer to the average.
Two standard deviations above the historical average is 50.7%, and levels above that mark are outliers.
FORBES: Bearish Expectations Haven't Been This Bad Since May 2010
The standard deviations are 11 percentage points for bullish sentiment and 10 percentage points for bearish sentiment.
Bullish sentiment is more than two standard deviations from its historical mean, making it a statistical outlier.
Playing in the tougher National League West, the Reds' 0.611 winning percentage was 2.86 standard deviations above the mean.
The larger the number of standard deviations of the spread from the mean, the higher the expected stock return.
Bullish sentiment is unusually low, but it would have to fall below 18% to be considered extraordinarily low (two standard deviations below average).
FORBES: Continued European Concerns Sink Bullish Sentiment Near Two-Year Low
He concedes he may have used the figure at some point, but now says that he had expected larger standard deviations on Nissen's data.
The company that carried out the analysis flagged all classrooms that showed a number of wrong-to-right erasures exceeding three standard deviations from the mean.
Bollinger bands, were developed by John Bollinger and generally are calculated by plotting two standard deviations above and two standard deviations below a 20-period moving average.
Weaver listened to Johnson babble about standard deviations for a while, then tossed out the printouts and continued to bat Johnson at the bottom of the order.
FORBES: Six Surprising Things About Orioles Manager Earl Weaver, Dead at 82
Goldman Sachs admitted as much when it said that its funds had been hit by moves that its models suggested were 25 standard deviations away from normal.
The 2.20 score indicates more than two standard deviations above the mean, meaning the Niners were more than twice as good as a typical NFL team that year.
FORBES: The Dominant Super Bowl Team Is Becoming Extinct - And That's Good For Business
For the statistics fans out there, that is a whopping three standard deviations away, a level that historically has been unsustainable and yielded to a sharp, albeit brief, upturn in stocks.
Only eight teams in MLB history have outdone the league by more than two standard deviations, including the 1984 Tigers, the 1986 Mets, and the Yankee clubs of 1998 and 1941.
The 1975 Cincinnati Reds of Pete Rose and Joe Morgan, winners of 108 games and a world championship, scored more than two full standard deviations above the rest of the league.
Stunningly, the typical answer-based tutoring systems average an effect size of around 0.35 standard deviations, and all three of the step-based, substep-based, and human tutoring cluster around an effect size of 0.75 standard deviations.
FORBES: How Machine-Based Tutoring Could Disrupt Human Tutors
By comparing average prices instead of actual prices, the standard deviations it uses as benchmarks are significantly tighter because the range of prices, which produce the standard deviations, has been squeezed tighter by averaging them first.
FORBES: Protectionist Antidumping Regime is a Pox on America's Glass House
We found that when earnings yield spreads during the prior five years averaged more than two standard deviations above the average, investors on average earned (annualized) returns on stocks of 21.3% for the following year, 17% for the next two years, 14.6% for the next three years and 8.3% over five years.
Bearish sentiment is at unusually high levels, but not so high that it would be considered extraordinarily high. (In statistical terms, pessimism is less than two standard deviations away from its historical average.) The sharp increase comes as the market has pulled back, some large-cap stocks have declined notably over the past several weeks and uncertainty about the fiscal cliff looms.
The key to this effort will be designing and implementing a credible and efficient process to determine which agency deviations from a standard set of requirements are truly required and what would be the best way to accommodate those deviations.
Deviations from the Standard Model prediction, if they are confirmed by more data, can shed light on these unknowns.
The system of homogenised best practices stimulated efficiency but it also blocked deviations from the standard, consequently limiting the discovery of new innovations.
However, academic research by Professors Mary Benner and Mike Tushman showed that its adoption could actually lead to a decrease in innovation after a few years (because ISO9000 does not allow for deviations from a set standard, which innovation requires), making the adopter worse off.
FORBES: Business schools suffer from a dangerous lack of evidence based teaching
To make all the curves comparable, he expressed the values of the actual deviations as fractions of a standard deviation, and their frequencies as proportions of their total number.
The standard deviation is calculated from all of the individual deviations of the data points.
应用推荐