The gray area around the average line shows the two standard deviation range of the data.
December is also the least historically volatile month, with a standard deviation of returns of 3.17%.
It's lost 0.3% a year over three years with a standard deviation of 14%.
Placing asset categories on the efficient frontier requires knowing their historical average return and standard deviation.
This is similar to the CAPM, but with standard deviation standing in for beta.
Or there is no investment with a lower standard deviation for the same expected return.
In statistical terms, optimism is more than one standard deviation above the historical average.
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Ideally, reviews and user reviews should generally fall within a standard deviation of each other.
As participants in any given activity improve across the board, says Mauboussin, the standard deviation shrinks.
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The standard deviation is calculated from all of the individual deviations of the data points.
One standard deviation is defined as the price band a security trades in 68% of the time.
It has done somewhat better, losing 0.8% annually the past three years with a 9% standard deviation.
One common yardstick of volatility is standard deviation, which uses annualized monthly returns over time as a baseline.
Pessimism is more than one standard deviation above its historical average, which makes it unusual, but not extraordinary.
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Proof of this can be found in the standard deviation, a measure of how volatile annual returns were.
Investments with a high standard deviation over one year have a lower standard deviation when measured over longer periods.
The last column in the table is also worthy of note, as it shows the standard deviation of returns.
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But the fluctuations in inflation in technical terms, a standard deviation of 0.24 have been smaller than ever before (see chart).
Optimism is currently more than one standard deviation beyond its historical average, meaning that this is an unusually high reading.
Rather it is just one standard deviation away from its average, making the current reading atypical, but not an outlier.
Specifically, I look to see whether bullish and bearish sentiment are within or beyond one standard deviation of their averages.
It is also more than one standard deviation below the historical average of 30%, making this an unusually low reading.
Nonetheless, optimism remains more than one standard deviation above its historic average of 39%-a sign that it remains at high levels.
Bearish sentiment is back to being more than one standard deviation above average, making it unusually high, but not extraordinarily so.
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Bullish sentiment is just slightly above one standard deviation from the historical average and bearish sentiment is within one standard deviation.
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The standard deviation formula goes like this: 1.1 x the amount bet x the square root of the number of hands played.
The most efficient investments are those such that no other investment has a higher return for the same amount of standard deviation.
Risk is the volatility of an investment as measured by standard deviation.
Consumer staples, which had a 10-year annualized standard deviation of just 13%.
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The MSCI Emerging Markets Index is only about a half of a standard deviation from its mean over the same time frame.
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