Tagged Questions

26 views

Substitution test for ANOVA?

I am working on biological dataset. Around 20000 genes of each sample are comparing with the same ones in another group in order to find significantly differentially expressed genes. I am comparing 3 ...
35 views

20 out of 30 gives me a probability but how to find statistical significance?

I compared Chinese and German websites and found that 20 out of 30 use the same design. So I got a probability of 2/3, right? Is there a way to find out if that probability is statistically ...
93 views

Combining p-values from different statistical tests applied on the same data

Although the title of the question appears trivial, I would like to explain that it is not that trivial in the sense that it's different from the question of applying the same statistical test in ...
21 views

How to count expected number of paterns?

Member of parliament can vote or can be absent during voting. Let assume: If, for a given MP, there is a pattern present-absent-present (010) in consecutive ...
89 views

Calculate the odds that a given name should have the first and last names swapped?

I have a personal project I'm working on and could use some help with the math. Let's say I had two lists. FN: 1 million first names (dupes allowed). LN: 2 million last names (dupes allowed). And ...
65 views

Is it sound to take the average of a cumulative average?

Sorry, I'm a huge statistics noob. I'm looking to find the probability that a certain event occurs in a binomial experiment. I take a few thousand samples per test, and then calculate the ...
97 views

Regression and point-specific p-values (using R for explanation)

Consider the following (in R): library(MASS) plot(stack.loss~Air.Flow,data=stackloss) regression <- rlm(stack.loss~Air.Flow,data=stackloss) abline(regression) ...
59 views

Working out probability with alpha and beta

Let's say in an experiment, the Null hypothesis is patients having Condition $\alpha$ (type I error) is $0.05$ and $\beta$ (type II error) is $0.15$. If I have a sample of 50 patients, 35 with ...
137 views

Conservative confidence interval

One month before the election, a poll of a large number of randomly selected voters showed 65% planning to vote for a certain candidate. The newspaper article reported a 90% conservative margin of ...
105 views

how can the probabilities of sampling subset proportions be tested?

Assume we have 10 different jigsaw puzzles. Each puzzle has a different number of pieces, e.g., ...
57 views

Comparing two points corresponding to two different normal distributions

I have two multi variate normal distributions N1 and N2. Say two points p1 is from N1 and p2 is from N2. I want to get some statistical features from these two points. How can I do it? I need a ...
28 views

Estimating the likelihood of independence of two discrete variables using the co-occurrence count matrix

I have some data about users from different regions visiting different directories of some website. Aggregating that data I get the co-occurrence frequency matrix (for regions and directories). Now I ...
71 views

I want to compare two groups of coin tosses with different number of tosses

I have a list of results of two different groups of coin tosses generated by http://www.wolframalpha.com/input/?i=10+coin+tosses. But the number of tosses is different: There are 10 in one group and ...
254 views

P values and t statistics?

I performed an experiment using two different methods on same object, the results of the experiments were Method 1 70,72,70,75 and 77% Method 2 80,81,67,75 and 82% On basis on average I claimed ...
194 views

80 views

Is there a way to test a probabilistic prediction for an uncontrollable experiment?

This is something that I've wondered about mostly in connection with weather forecasting, but I would like to ask the general question because it comes up from time to time in other contexts. Suppose ...
117 views

Testing that a sample corresponds to an arbitrary distribution

I'm writing a set of unit test for a function that draws random numbers from an arbitrary distribution, defined as a PDF (example of such a function can be seen here). I am confused about the proper ...
132 views

Testing against a custom probability distribution

What I want is some tool that will test an ordinal, discrete variable against a specific probability distribution, say the variable might take 4 values, 1, 2, 3, 4, and my expected probability ...
7k views

How to find P(X > F) in ANOVA F-test?

(Apologies for the ASCII tables, Stackexchange doesn't allow HTML tables and since I'm not supposed to link to an image, this is the only way I know of showing the data) I'm learning about ANOVA ...
124 views

Probability that X<=Y when X and Y are p values from two different hypotheses

If i test two hypotheses, one of which has a null that is -in fact- false and the other has a null that is -in fact- true, I want to know the probability that the first test will obtain a p value less ...
294 views

How to calculate sample size for a one-sided test on a rxs contigency table

I work quite often with Google's Website Optimizer, essentially it allows you to make small changes to a site to determine if they have an effect on the ratio of clicks to a web page to sales. The ...