Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [statistics]

21 questions
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6 answers

Statistical accuracy of multiple resistors in series or parallel

I'm having a senior moment and would appreciate clarity. I'm working on an inverting amplifier design where I need to add low-pass filtering and a voltage clamp. Without the filtering and clamp, the op-amp configuration would simply be a feedback…
Dwayne Reid
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What is the physical significance of skewness and kurtosis of an eletrical signal?

I understood the mathematical meanings of the skewness and kurtosis. But when we calculate these quantities for a signal (say an electrical voltage signal), what physical meaning do they convey? For e.g. I understood mean as the DC component of the…
Aditya
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Why are different RMS noise sources added in this way?

I'm wondering why noise sources are added such a way their RMS values are added in square root of sum of squares fashion. For instance if the RMS noise values from three sources are X,Y and Z, then the total noise is given as \$N =…
cm64
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when to use auto correlation and when to use fourier transform

In communication, if we don't know any prior information about the signal, we perform an auto correlation say Rx(T) and take the Fourier transform of Rx(T) to analyze the power spectrum. Supposing if my signal is known do i need to perform auto…
phanitej
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Statistical noise measurement

Is there an accepted measure of noise in a data set? I am taking a series of reading from an ADC, which follow a trend (they are not random data points). However, they generally lie above and below the averaged value (running average, FIR low pass…
user32885
2
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1 answer

How to monitor Ethernet packet loss real time on different connections?

For an embedded application we have a network with star topology, where we want to determine if there is packet loss for the different point-to-point (SMAC => DMAC) connections. We consider inventing some scheme where the source (SMAC) sends a…
EquipDev
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PCB Thickness Variability

How much variability is there in the thickness of a standard PCB? Let's say I order a 1.6mm FR-4 board. Will the actual thickness range 1.5mm-1.7mm? 1.4mm-1.8mm? 1.59mm-1.61mm? What is the (approximate) value of x in "1.6mm ± x%"? What if the board…
T. K.
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Random Error Waiting Time

Suppose that you have a design that has had an error after running 14, 18, and 20 hours. You're not exactly sure what is causing the error, but you make a change to the design that MIGHT fix it. How long do you have to run without seeing an error…
crj11
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Number of data points needed for INL DNL estimation

In this article where ADC of pico pi is characterized, I found a part that I have never encountered in my study of mixed signals design: I don't understand how we number of data points needed is derived and how it is related to N and DNL…
Kutsit
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Estimating shot noise - what's the origin?

If I have some photon detector, say a CCD, how do I estimate the error introduced by shot noise correctly? Typically, sources found on the internet say that the shot noise is the square root of the number of electrons counted (multiple sources…
hintze
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Are there more (mains) electrical safety incidents in the United States compared to the UK?

Forgive me if this question isn't exactly "on topic" for this site -- it's a bit meta. I am an academic in the UK, and I occasionally design electrical devices that plug into "the mains" in one guise or another. Some of these are (novel) medical…
Landak
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Stochastic Processes wtih respect to the electric load demand

I am required to look at the statistics (stationarity, mean, standard deviation etc) of the electric load profile. I decided to use the load data for the IEEE reliability test system as it has all the data for an entire year. More specifically I…
Edmund Blackadder
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What is the statistical accuracy of a Reference Voltage based current source?

I would like to make a current source from a reference voltage chip (REF102). OPA277 is used as a buffer to pin the voltage at pin 4 to the bottom of the current setting resistor R. Hypothetically, if the reference voltage chip outputs a voltage at…
Efanatic
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Suspicious definition of erlang distribution in Verilog-2005 spec

The $dist_erlang function in Verilog-2005 takes an argument called mean. Some information about the mean argument of $dist_erlang is found in this paragraph from section 17.9.2 of the spec: They also provide C code for how simulators ought to…
John M
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measurement errors: add up or cancel out?

Take an accelerometer, or a hall sensor, or a thermometer, or any sensor. It will have an accuracy, which means the readings will contain some error of this sort. My guess is that by taking a big number of readings of the measured parameter will…
kellogs
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