If our measure was just capturing
random noise in the data rather than information about true principal quality, we would not expect it to be related to teacher quality and turnover.
I have read with interest the paper by Santer et al indicating that the statistical work by Douglass et al is flawed because they had not allowed for natural
random noise in the data set of measurements in upper tropospheric temperatures.
Not exact matches
In nearly all real - world data, there are short - term fluctuations, random effects, and other influences that create «noise» in the values that we observ
In nearly all real - world
data, there are short - term fluctuations,
random effects, and other influences that create «
noise»
in the values that we observ
in the values that we observe.
Even statistical
noise — or
random variation
in neutron measurement — would convey no
data.
In recent decades, advances in telescopes and sensing equipment have allowed scientists to detect a vast amount of data hidden in the «white noise» or microwaves (partly responsible for the random black and white dots you see on an un-tuned TV) left over from the moment the universe was create
In recent decades, advances
in telescopes and sensing equipment have allowed scientists to detect a vast amount of data hidden in the «white noise» or microwaves (partly responsible for the random black and white dots you see on an un-tuned TV) left over from the moment the universe was create
in telescopes and sensing equipment have allowed scientists to detect a vast amount of
data hidden
in the «white noise» or microwaves (partly responsible for the random black and white dots you see on an un-tuned TV) left over from the moment the universe was create
in the «white
noise» or microwaves (partly responsible for the
random black and white dots you see on an un-tuned TV) left over from the moment the universe was created.
To fix it, Checkmarx says Tinder should not only encrypt photos, but also «pad» the other commands
in its app, adding
noise so that each command appears as the same size or so that they're indecipherable amid a
random stream of
data.
This is extremely simple: for one shot of this we take the trend line and add
random «
noise», i.e.
random numbers with suitable statistical properties (Gaussian white
noise with the same variance as the
noise in the
data).
Precisely that question was addressed by Mann and coworkers
in their response to the rejected MM comment through the use of so - called «Monte Carlo» simulations that generate an ensemble of realizations of the
random process
in question (see here) to determine the «null» eigenvalue spectrum that would be expected from simple red
noise with the statistical attributes of the North American ITRDB
data.
The issue if there is a
random component (
noise)
in the
data points.
This is particularly clear if we consider the most recent 30 years of the series (shown
in figure B) and use these statistical tools to «filter» the
data (
in an effort to reduce the amount of
random noise).
But, although it will increase the power
in a power spectrum, we obviously agree that it won't increase the physical amplitude of a signal, or the variance of the
data even if they're nothing but
random noise.
You mention» standard deviation of a set of non-
random numbers» The numbers were generated on a spreadsheet using Excel's
random number generator so they the net result was what,
in electronic terms, I would say was real
data (signal) and unwanted randomness (
noise).
Now, you turn around and say essentially, «Well, yes, it may be demonstrably true that a (synthetic) series that we know has an underlying linear trend plus
random noise behaves
in the same way as the actual
data, but I want to believe that
in this case it is really due to something different.»
It is not hard to demonstrate this sort of thing
in this particular case by creating «artificial
data» that has a linear trend plus some sort of
random noise.
I can generate completely
random data without any trend with
noise mimicking that
in annual temperature
data and quickly find a 13 - year span somewhere
in the mix that would appear to have a trend that's positive within a 95 % confidence interval (with an equal probability of seeing a «significant» decline).
See, the first thing to do is do determine what the temperature trend during the recent thermometer period (1850 — 2011) actually is, and what patterns or trends represent «
data»
in those trends (what the earth's temperature / climate really was during this period), and what represents
random «
noise» (day - to - day, year - to -
random changes
in the «weather» that do NOT represent «climate change»), and what represents experimental error
in the plots (UHI increases
in the temperatures, thermometer loss and loss of USSR
data, «metadata» «M» (minus) records getting skipped that inflate winter temperatures, differences
in sea records from different measuring techniques, sea records vice land records, extrapolated land records over hundreds of km, surface temperature errors from lousy stations and lousy maintenance of surface records and stations, false and malicious time - of - observation bias changes
in the information.)
General Introduction Two Main Goals Identifying Patterns
in Time Series
Data Systematic pattern and
random noise Two general aspects of time series patterns Trend Analysis Analysis of Seasonality ARIMA (Box & Jenkins) and Autocorrelations General Introduction Two Common Processes ARIMA Methodology Identification Phase Parameter Estimation Evaluation of the Model Interrupted Time Series Exponential Smoothing General Introduction Simple Exponential Smoothing Choosing the Best Value for Parameter a (alpha) Indices of Lack of Fit (Error) Seasonal and Non-seasonal Models With or Without Trend Seasonal Decomposition (Census I) General Introduction Computations X-11 Census method II seasonal adjustment Seasonal Adjustment: Basic Ideas and Terms The Census II Method Results Tables Computed by the X-11 Method Specific Description of all Results Tables Computed by the X-11 Method Distributed Lags Analysis General Purpose General Model Almon Distributed Lag Single Spectrum (Fourier) Analysis Cross-spectrum Analysis General Introduction Basic Notation and Principles Results for Each Variable The Cross-periodogram, Cross-density, Quadrature - density, and Cross-amplitude Squared Coherency, Gain, and Phase Shift How the Example
Data were Created Spectrum Analysis — Basic Notations and Principles Frequency and Period The General Structural Model A Simple Example Periodogram The Problem of Leakage Padding the Time Series Tapering
Data Windows and Spectral Density Estimates Preparing the
Data for Analysis Results when no Periodicity
in the Series Exists Fast Fourier Transformations General Introduction Computation of FFT
in Time Series
They're artificial
data which I created with a known warming trend of 0.012 deg.C / yr plus
random noise (which
in this case is the simple kind known as «white
noise»).
If the past, pre-industrial variations were considered as
random NOISE, there would be nothing significant
in the observed
data, especially if you consider homogeneous measurements (through proxies).
However, I think that Roger Pielke, Jr. has a point when he suggests that accurate short - term forecasts are used to show how reliable the GCMs are, but inaccurate short - term forecasts are attributed to
random noise in the actual
data.
While litigants and law firms would no doubt like to use legal
data to extract some kind of informational signal from the
random noise that is ever - present
in data samples, the hard truth is that there will not always be one.