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For Mathematics....
I have these series of numbers:a) 1.4, 2, 2.1, 3.1, 3.2, 4b) 4, 3.2, 3.1, 2.1, 2, 1.4Both series have the same mean and variance...But I like a before b (a it is increasing, and b is decreasing...)What descriptive statistic would you use???I know a) is positive and b) is negative...But what is the easy method that give me a number to select a serie...
Last edited by mtarazona on November 8th, 2007, 11:00 pm, edited 1 time in total.
For Mathematics....
QuoteOriginally posted by: mtarazonaI have these series of numbers:a) 1.4, 2, 2.1, 3.1, 3.2, 4b) 4, 3.2, 3.1, 2.1, 2, 1.4Both series have the same mean and variance...But I like a before b (a it is increasing, and b is decreasing...)What descriptive statistic would you use???I know a) is positive and b) is negative...But what is the easy method that give me a number to select a serie...slope over time ?
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- ZmeiGorynych
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For Mathematics....
If you care whether it grows or falls, look at first difference, eg Sharpe ratio of.
For Mathematics....
Yes I Know the first difference...But Let me know to show 3 series:a) 1 , 4, 5, 20b) 1, 10, 30, 40c) 1, 25, 40, 80The series are very different...The easy idea is use this ratio(20-1)/4 < (40-1)/4 <(80 -1) /4 I want to use a different method, to select a 2 time series of returns, I use a mean and variance, but I want a number .... it gives me a easy form the trend of the serie...Thanks
Last edited by mtarazona on November 11th, 2007, 11:00 pm, edited 1 time in total.
For Mathematics....
QuoteThe easy idea is use this ratio(20-1)/4 < (40-1)/4 <(80 -1) /4 Thats really a bad idea. Just throw into the garbage all the info in the middle of the series? For instance:a) 1 3 4 10equals to b)1 23 23 10You really need to clear it up. I cant understand what you're saying.What to you want to do with the series? Its clear that you want to select them, but with which quality in mind and to what purpose?
For Mathematics....
Are your series something like stock data? If so we can assume, given the same variance of returns, you want to choose the stock with the greatest mean return. So convert your series to returns and find the mean return. If your return series have different variances you should take a look at the Almost Stochastic Dominance decision rule.