Questions tagged [odds]

The odds of an event is the ratio of the probability that the event will happen (p) to the probability that it will not happen (1-p).

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What are the odds [duplicate]

What are the odds Ive met my other half? Thing is I already know I have with this undeniable experience we had when our souls actually collided together as we were one. I just want to know what ...
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What probability or weight should I assign to X so that it has a Y% chance of being one of the 6 items selected out of a population of 12?

I have a population of 12 items, let's call them A through L. I'm going to be drawing 6 of those items out of the population without replacement. So you can't choose the same item twice. What I know ...
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What is the difference between standardized mortality ratio (SMR) and odds ratio (OR) from age matched case and controls?

My question refers specifically to comparisons of chronic diseases, say heart failure (HF), between a specific group of interest (eg, diabetics) and a reference group (non-diabetics). SMR is the ...
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Generate odds ratios across deciles / quantiles of an indpendent variable

With reference to the following figure from Bellomo et al., 2011: How exactly are the odds ratios across the deciles 'referenced against the 4th decile' calculated? My initial impression is that a ...
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Multiple non-independent tests, how to determine post-test odds

Let's say a patient receives two biomarker tests to help with diagnosis of a disease. Each test measures a different mechanism of the disease, but these two mechanisms are not independent, so the ...
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Betting odds with team win and draw

So a game can have 3 outcomes: Team 1 wins: 36% chance. Payout is 2.15 Team 2 wins: 34% chance. Payout is 2.45 Game is a draw: 30% chance. Payout is 2.66 How should I be thinking about making one or ...
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When Can I say odds ratio is important to analyze my data

Lets say in my data if I generate odds ratio between 2 variable A and B and get that the odds ratio is 2-5 is that a good thing to dive deep further or should I move to other relations .
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What are the selection odds

If 30 ice-cream sticks are numbered 1-30 and placed in a bowl, what are the odds that when picking two at a time, and then returning them to the bowl, any random pair will never be picked?
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If I have the implied probability of something how do I convert that into decimal odds? [closed]

I'm really struggling to find examples of converting implied probability back into European decimal odds. Say I have the implied probability of a horse to win at 66% of the book (no overrounds for ...
525 views

Computation and Interpretation of Odds Ratio with continuous variables with interaction, in a binary logistic regression model

Question A binary logistic regression model has been fitted, with the following output; ...
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SPSS - Binary logistic regression: classification cutoff

Let's say I want to evaluate the predictive value of a continuous variable in the prediction of malignancy (event/status) of a tumour. Malignant = 1 Nonmalignant = 0 In SPSS, I can run a binary ...
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Difference in logits to difference in probabilities

a) Is there any way to prove that you cannot compute a probability difference when you know a logit difference? b)In general, is there some acceptable way to convert distances in logodds space to ...
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Betting with odds

I have a game where I can bet on two teams: One team has odds $1.7$ The other has $1.5$ I understood that the one that pays off $1.5$ has an higher probability of victory, so it pays less. But how ...
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Odd Number Probability

How do I calculate the probability of randomly picking a number in the range from 0 to 10000 where exactly two of the digits is odd. For ex 5001 or 1010 etc.. and how would I do the same calculation ...
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3 D6 pick 2 vs 2 D6 with 1 reroll

I was wondering if there is any statistical difference between rolling three 6 sided dice and taking the best two (looking for a 7 or higher) and rolling two 6 sided dice with the option to re-roll ...
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Is there a possibility to calculate the odds of the following scenario?

The following is a true situation that I faced and I was wondering if it is possible to roughly estimate the odds of it happening (like you sometime see rough estimations of "The odds of you winning ...
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Logistic regression with independent variable values less than 1

I have one independent variable which has values less than 1, and want to see how the odds of having a disease change when the independent variable increase by 0.1. I ran a binary logistic regression ...
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Crude odds ratio

I came across following definition of crude odds ratio in binary logistic regression: Crude odds ratio is when you have only one independent variable And also I heard: Crude odds ratio is when ...
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How are these odds created?

I've always been a bit baffled by how Vegas creates sports odds. Not so much the process of how did the oddsmakers decide that Option A has odds of X/Y (that obviously is fairly subjective and not ...
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Unbiased estimators of the log odds

In the book of Lehmann and Casella (2003) page 83, a random variable $X$ is distributed according to the binomial distribution $Bin(n,p)$, $n$ the number of trials and $p$ the success probability. ...
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Odds Ratio and gene mutations association

I have a simple (yet to me still trivial) problem to submit to you. I have a dataset of a group of patients affected by a disease, for which the presence of several genes mutations was inferred. Each ...
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What is a simple intuitive definition of Odd? [duplicate]

From what i read "The probability that an event will occur is the fraction of times you expect to see that event in many trials. The odds are defined as the probability that the event will occur ...
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The difference between the logits of two probabilities is the logarithm of the odds ratio? Correct/Incorrect?

I was reading a Wikipedia article on the logit function, and I came across the following in the definition section: If $p$ is a probability, then $p/(1 - p)$ is the corresponding odds; the logit of ...
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model building including very large or very small OR

I am using logistic regression for a binary outcome. When building a multivariate model, is including insignificant univariate variables with OR >0.5 and <1.5 appropriate? And why?
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What are the odds of both my Grandmothers passing away on the same 24 hour day? [duplicate]

Yesterday (April 7th, 2018), my Grandmother from my Mom's side passed away. Later on that same day, less than 24 hours apart, my other Grandmother (Dad's Mom), passed away. My question is simple; what ...
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Interpreting odds ratio of multiple comparisons from a logistic regression model (using R)

I recently ran a logistic regression on categorical data and ran a Tukey multiple comparisons post hoc analysis using the glht ...
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95% confidence interval for log odds

I'm looking at data from the O-Ring Challenger disaster and wasn't sure how to get a 95% confidence interval for a particular estimated log odds. In this case, I'm considering a logistic regression ...
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How to average “Odds likelyhood” when probabilities from multiple models are involved?

I am trying to understand a problem confusion. Say, we have two models (m1 and m2) that predicts probability of "rain" on a particular day. If I am trying to calculate average odds of rain, which ...
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There are 100 people in a room. What are the odds that the shortest person in the room is born in February?

This is a follow up question to the previous "There are 100 people in a room. What are the odds at least 1 person is born in January?"
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Correct way to interpret odds ratio

I'm looking at a table of logistic regression results. Specifically, the table shows "Logistic regression model of hypertension status in relation to lead biomarkers in the normative aging study, ...
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Optimal wager strategy for high win chance / high odds game

In a rigged game of chance where statistically I am expected to win, is there a difference in terms of expected profits, risk, etc - between betting the same amount of money each time (for example ...
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Logistic regression to test difference between two groups with multiple levels

I have a dataset (see example below) with 1200 rows and 3 columns: dependent_var (yes and no), group_var (1 and 2) and var1 (1, 2, 3 and 4), where var1 belongs to either group 1 or 2. The two groups ...
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Reporting a Negative Logit/Log Odds as an Odds Ratio for a Continuous Predictor in Logistic Regression

In the social sciences, people typically report and interpret an odds ratio (OR) < 1 for a binary predictor which has a negative association with a binary outcome. But the social sciences, of ...