Questions tagged [systematic]
The systematic tag has no usage guidance.
17
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Linear regression with statistical and systematic error in y and statistical error in x
I was wondering what is the best way to perform a linear regression if I have a data with uncertainties in $y_i$ and $x_i$ (which are not necessarily the same). And suppose that $y_i$ has a systematic ...
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90
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Systematic error in time series simulations(?)
Statistical models of time series tend to underestimate points above average and overestimate points below average, due to regression to the mean. If points above and below average are treated ...
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2
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862
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What is systematic information in a statistical model / random variable? What can be deterministic about something random?
Often, we try to model data $ \{(x_i, y_i): \ i=1,2,...,n \}$ by assuming a "data generating process" for the data:
$$Y = f(x)+\epsilon$$
where we call $f(x)$ the (deterministic) "...
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Confused About Systematic Sampling
So I was going through my notes and ended up extremely confused about a couple of things.
1.Suppose I have 20 employees and my population size is 200. I know that I need to take 200 and divide it by ...
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146
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Error on distribution of values with uncertainties
I'm currently analysing a measurement which results in a high number of values, each having a slightly different uncertainty.
These values are following a gaussian distribution, so I wrote a python ...
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1
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115
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Simulate data including systematic error!
for my bachelor thesis, I am doing a simulation study in order to compare analysis methods.
The generated data is a pre-post design data, with two groups measured at two times.
...
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1
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760
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Consider systematic error in a fit
My question arise directly from a lab situation.
Let's say I have measured two sets of data $x_i$, $y_i$ and i know both the statistic and systematic error for $y_i$ (I assume no error on $x_i$). ...
3
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748
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Confidence interval of AUC with Reitsma model in mada R package
I am conducting a meta-analysis of diagnostic test accuracy studies comparing myocardial perfusion scintigraphy vs coronary angiography using the mada R package.
I ...
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2
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5k
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How to carry out adjusted indirect comparison or 'Bucher method' meta-analysis
I have carried out a pairwise meta-analysis of Drug 1 vs. placebo and a pairwise meta-analysis of Drug 2 vs. placebo (I have used RevMan software to do this). From each meta-analyses I have an overall ...
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1
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123
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Drawing a systematic sample
Please clarify the following question:
If two independent systematic samples of size
four each from a population of 36 units have y-values of a characteristic y as:
24,26,22,28 and 27, 25, 23, 29
...
4
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1
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133
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Test for compairing data on same days in a week in different years
So I'm doing some power system analysis on active and reactive power loads and I'd like to compare the data from 2015 and data from 2015 to see how much they differ. The nature of the load is such ...
2
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236
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Calculating group size from hazard ratio
I am undertaking a systematic review and as part of the data extraction process I would like to know how many patients were analysed in the treatment and control arm (in a particular subgroup). In one ...
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122
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Statistic test when bias is not random
Is there a statistical test that I can use to say that there is bias in the result of my analysis but the bias only occurs at certain region. The scatter plot below probably will make more sense:
...
2
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2
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3k
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Systematic Sampling with unequal probabilities
I found the library Sampling in R to conduct a systematic random sampling with unequal probabilities. I got my sample but I really don't know how that sample is selected. Is there anyone that can ...
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1
answer
577
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Mixing ITT and TOT/LATE Effect Sizes in Meta-Analysis
I have a question concerning the coding of Effect Sizes for a large (educational) Meta Analysis with mostly latent outcome variables.
Some studies provide "Intent to Treat" Data from which I ...
3
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1
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4k
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How to sum uncertainties, systematic and random
I apologize for the simplistic questions. I have a retrieval process that has a set of random and systematic uncertainties associated with it. I'm assuming that these are all independent. The goal is ...
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132
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Incorporating systematic uncertainty in interval estimation
I am trying to fit some binomially distributed data to a model. There is a reasonable systematic error associated with the measurements. This uncertainty comes from imperfect theoretical knowledge of ...