Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [false-positive-rate]

In a test for a condition (such as a disease) the false positive rate is the proportion of subjects incorrectly classified as having the condition.

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FPR (false positive rate) vs FDR (false discovery rate)

The following quote comes from the famous research paper Statistical significance for genome wide studies by Storey & Tibshirani (2003): For example, a false positive rate of 5% means that on average 5% of the truly null features in the study…
Naseer
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Best way to reduce false positive of binary classification to exactly 0?

I'm working on a task that even a 0.00001 fp rate is not acceptable, because detecting something as a positive when its not will have very bad consequences in this task, so it needs to be exactly 0 in my dataset when i use k fold, so 0 for each…
OneAndOnly
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How many coin flips are needed to reliably know a coin of weight w is unfair?

I want to find out how many flips I need to flip a coin to reliably know that it is an unfair coin. The issue is that as the coin becomes closer to 50/50, the more false-negatives you will have if you don't take dramatically more data. I wrote some…
Steven Sagona
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When using ROC curves for WWII Radars, what was the TN?

One of the origins of ROC curves seems to be to compare radar systems in WWII (source). How did they actually compute the False Positive Rate when they didn't have an estimate for True Negatives? If I understand correctly, the FPR is FPR =…
brnl
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Estimating positive and negative predictive value without knowing the prevalence

There is a lot of discussion about the positive predictive value of a test currently. I know that if I know specificity, sensitivity of a test and the prevalence $p$ in the sample, then I can easily calculate the positive predictive value (ppv) and…
LiKao
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Number of samples required to estimate a desired False Positive Rate

I have an algorithm that for each sample $x_i$ returns an anomaly score $0th$. During cross validation the threshold is set in order to have the desired…
Donbeo
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Relationship between Recall, TPR, FPR and Precision

Can Precision and Recall be used to Generate TPR or FPR? In other words, is there any formula that relates the following Evaluation metrics? True Positive Rate (TPR) with either Precision or Recall (e.g. TPR = 1-[Precision/Recall]) False Positive…
abafo22
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Is Partial Correlation useful for noisy data?

Explaining The Problem Important question in data analysis is testing observed relationships for confounding factors. Partial Correlation is a metric designed to do specifically that. The general idea is as follows. If random variables $X$ and $Y$…
Aleksejs Fomins
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ROC curve from an array of Confusion Matrices (true positive rates and false positive rates)

How can we create an ROC curve from an array of Confusion Matrices (true positive rates and false positive rates)?
Vic
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Formula for expected false positive & negative rates in hiring decisions based on r

I would like to look at the size of the expected false positive and false negative rates in employment hiring decisions. Let's assume that it is useful to dichotomize job performance after hiring. The hiring decisions are based on a predictor with…
Joel W.
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Aren't all tests sensitive to the prevalence of a disease in the population?

I'm trying to understand the difference between the false-positive rates of two kinds of COVID-19 tests: PCR and antibody. The former indicates if someone is currently sick. The latter indicates if someone was sick in the past. Per…
Gili
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Base rate of accuracy after resampling for classification problems

If I had an imbalanced dataset with 10% positive instances and 90% negative ones, the base rate for accuracy before resampling is 90%. But what about I resampled the data such that I have an equal amount of positive and negative instances? Will 50%…
Chong Sun
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What is "positive"?

I'm deeply confused by some concepts. We often hear the term true/false positive/negative. While it is straightforward to tell if the result is true or false, I find it confusing to tell if it is positive or negative. In hypothesis testing: Let's…
youkaichao
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How to interpret a False Discovery Rate plot

It is the first time that I am trying to calculate the FDR and I use the fdrtool package in R. I want both, local and tail area graphs and I think the third subplots of these examples summarise the information. However, I have a rather basic…
foo
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Is most published research indeed false?

I have come across (Ioannidis, 2005) which explains several reasons (mainly statistics-related, that's why I post this question here) to justify the claim that most published research is indeed false. Phys.org, Beware those scientific studies—most…
David
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