# 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 get odds ratio in a table in SPSS?

I have survey data from students from two Universities. One of the questions in the survey had 4 response categories and students were allowed to check only one (categorical variable). I want to make ...
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### Combined odds ratio

I wonder if there's a way to calculate the combined odds ratio for certain SNPs in a meta-analysis of a several GWAS, even when you don't have the SE, neither beta, for each individual study? Thank ...
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I need some help to understand some topics in Agresti's Categorical Data Analysis. In section 6.3.1 (p 231), he provided a model like: $$\text{logit}(\pi_{ik})=\alpha+\beta x_i+\beta_k^Z$$ where ...
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### Comparing odds ratios of continuous and discrete variables

I need to compare the ability of two methods to predict an event with a binary response. Each method produces a score, where the higher score indicates 1 and a lower score indicates 0. I am looking to ...
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### Adjusting data for age and bmi

I am doing a study on the effects of bad blood sugar control on patients. BMI, age, type of diabetes (Type 1 and 2 or gestational diabetes) are all variables. Outcomes include C section, early labour ...
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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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### 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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### 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 ...
398 views

### Odds ratios multiple comparisons

I have to assess for each product p, the odds ratio associated (success/failure). The data are in this table: ...
463 views

### 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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### 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 ...