proportions

  1. E

    Stacked bar plot for proportions of factor variables

    [SOLVED] Stacked bar plot for proportions of factor variables Hello everybody, I'm having a problem making a stacked bar plot. I wish to make a stacked bar plot with on the y-axis the proportion (from 0 to 1) of a factor variable called 'species' (there are 4 different species) and on the...
  2. U

    Adjusted Chi-squared test for clustered binary / categorical data

    I'm looking for some assistance in statistical analysis with R (ideally), but also some general stats advice. This follows from a review which identified the need for me to adjust for clustering of relatives within family groups in my data set. I am investigating cardiac phenotypes (I'm a...
  3. M

    Need quick reply

    If I have three categories (yes, no and don't know) for a single variable (say Effective_policies_in_hospital) with 50% 25% and 25% respectively... I am only interested to test whether this 50% is significant... Can I run prtest from stata by coding these three categories 1 0 0 and testing it...
  4. S

    Proportions test

    Iam interested in assessing if my proportion is significant. I have no clue what to do and how to do it. I use R for programming. I appreciate your help. I have random list of genes (200). These genes are involved in a particular process and I call this as a ProcSet. In an experiment, I am...
  5. D

    Confidence intervals, proportions

    A simple random sample of 1000 New Yorkers finds that 87 are left-handed. (a) Find the 95% confidence interval for the proportion of New Yorkers who are left-handed. The answer my professor gave and the answer that I got are completely off from each other. Here is what I have so far n = 1000...
  6. C

    Can I use a chi-square test for this 2x3 contingency table?

    Imagine I want to find out whether there are any differences between male and female participants in their pet choices, and this is my 2x3 contingency table: ___________ Dog_____Cat_____Bird Male_______ 75_____ 51_____ 27 Female _____60 _____ 80 _____ 9 Note I don't have the same amount...
  7. J

    Null hypothesis

    4. http://i42.tinypic.com/2woyqgz.png 10. A physician claims that as soon as his patients have a positive pregnancy test, he is generally able to predict the sex of the baby and that his probability of being right is greater than the one-half that would be expected if he were just guessing. A...
  8. S

    Proportions through time

    Hello all, this seems like it should be a simple questions but our team cannot find an answer to the question. If I have data set up like the following (the numbers are the percent of that fruit rotten): 2007 2008 2009 2010 Fruit A 59 62 61 62 Fruit B 50 49...
  9. R

    comparing percentage when without knowing n? what test?

    I'm trying to do a meta analysis of some poll results and though I know the sample size in general, if I'm comparing the reported results and they say things like "78% of Toyota owners like baseball" but they don't say which percentage of people overall were Toyota owners, can I still test for...
  10. S

    Fishy problem- which stat is appropriate? t-test or mann whitney

    Hello kind stats people, I'm in a bind! In my PhD I'm studying fertilisation success of 2 species of fish when they mate with each other. So how does mating success as a hybrid compare to that of the pure male. And just to complicate things I have them mating in different orders to see if...
  11. S

    continuous random variables help

    continuous random variables: basically, if you guys can answer this question for me and explain how its done I should be able to do the rest of the assignment in this area. The 2007 Toyota Camry Hybrid (automatic, 2.4-litre, 4-cylinder) has an average fuel consumption of 6.5 litres per...
  12. T

    testing for significant diffs between proportions

    Thanks for stopping by, I have a question about analysing responses from a multiple choice question. I'm looking at a question on what topics people talk discuss most online- there was a list of about 30 topics, and participants were able to pick more than one option. I'm not sure how to...