# Tagged Questions

Refers to a measure of association between two binary variables. If $X,Y$ are binary outcomes and $p_{ij} = P(X=i,Y=j)$, the odds ratio is equal to $${\rm OR} = \frac{ p_{11} p_{00} }{ p_{10} p_{01} }$$ When ${\rm OR} 1$ indicates a positive relationship. More info is available at ...

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### How to calculate odds ratio and p-values for Fisher's test?

I'm trying to perform Fisher's exact test in R. I'm calculating odds ratio like this \frac{(\text{no. of successes in my set}) \cdot (\text{no. of failures in background set})}{\text{(no. of ...
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### Odds Ratio Between Overlapping Groups

Is it inappropriate to use odds ratio for groups that are subset of each other? For example, comparing GPA of female students to GPA of all the students. (This is just an example, not what I am really ...
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### The effect of skewed continuous predictors in a binary logistic regression model

I am analyzing data with a binary outcome and a variety of continuous and categorical (including dichotomous) predictor variables. My approach is to perform a binary logistic regression and to treat ...
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### Poisson regression to estimate relative risk for binary outcomes

Brief Summary Why is it more common for logistic regression (with odds ratios) to be used in cohort studies with binary outcomes, as opposed to poisson regression (with relative risks)? Background ...
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### Can odds ratios increase if you include more variables?

Suppose one wants to compute the odds ratio of a disease for a person in group $A$ versus that of a person in group $B$. Suppose we consider the following: (i) include age in the odds ratio ...
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### Odds ratios question

If you have a categorical variable with $k$ levels (so $k-1$ indicator variables), is there an easy way to calculate the odds ratio? Suppose the first level is the reference level. The model would be ...
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### How to conduct a meta-analysis on studies that report results variously as odds ratios, hazards ratios, or rate ratios?

I'm doing a meta-analysis of some studies that report results variously as odds ratios, hazards ratios or rate ratios (all with confidence intervals). Is there any way to combine these ...
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### Generating data with a pre-specified odds ratio

I have to simulate (in javascript) the likelihood that members of a certain population would have a disease, given a contextual value. All information I have comes from papers that show odds ratios ...
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### What is the best statistical method to compare case fatality rates of 17 years for 2 different states?

I have Case Fatality Rates (deaths per 100 cases) for 2 different states receiving different treatments for 17 years. What is the best statistical method to compare Case Fatality Rates ? The data ...
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### Odds ratios multiple comparisons

I have to assess for each product p, the odds ratio associated (success/failure). The data are in this table: ...
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### How to calculate confidence intervals for pooled odd ratios in meta-analysis?

I have two datasets from genome-wide association studies. The only information available are the odd ratios and their confidence intervals (95%) for each genotyped SNP. My want to generate a forest ...
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### Logistic Regression in R (Odds Ratio)

I'm trying to undertake a logistic regression analysis in R. I have attended courses covering this material using STATA. I am finding it very difficult to replicate ...
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### How to assess effect of intervention in one state versus another using annual death rate data?

I am a beginner in statistics. I have these unpublished data (cases and deaths) of a disease for 7 years (2004-2010) from 2 neighbouring states. The study was started in 2004. State 1 and State 2 ...
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### What does “case-control” and “cross-sectional” mean in the context of logistic modeling?

While studying logistic modeling, I read the following statement The fact that only odds ratios, not individual risks, can be estimated from logistic modeling in case-control or ...
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### Probability calculation, system uptime, likelihood of occurence

(redirected here from mathoverflow.net) Hello, At work I was asked the probability of a user hitting an outage on the website. I have some following metrics. Total system downtime = 500,000 seconds ...
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### Meta analysis on studies with 0-frequency cells

I am familiar with meta analysis and meta regression techniques (using the R package metafor from Viechtbauer), but I recently stumbled on a problem I can't easily ...
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### Relation between logistic regression coefficient and odds ratio in JMP

From the output of a logistic regression in JMP, I read about two binary variables: Var1 estimate -0.1007384 Var2 estimate 0.21528927 and then ...