p value

  1. E

    Overlapping confidence intervals and p values

    Hi, I've been given the mean and 95% confidence interval (CI) of two independent groups and asked if they were satistically significantly different or not? I know that if the CIs of the two groups don't overlap at all, then they can be considered as significantly different. However if the CI do...
  2. S

    P values from bootstrap in R

    I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample (basically input a...
  3. S

    Extracting p value from bootstrap

    I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample (basically input a...
  4. S

    Getting p-value for rsquared bootstrap in R

    I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample? # Bootstrap 95% CI for...
  5. M

    Age-adjusted P value

    Hi, I have a table of baseline characteristics of a cohort in which I have compared the differences between those with kidney disease and those without, using a combination of Chi-square test, t-test, or Kruskall-Wallis test as appropriate. How do I age-adjust the P values that I get from these...
  6. K

    Hypothesis test for the difference of two means, should I consider annualized or monthly returns?

    I have 10 years monthly returns. I calculated annualized return multiplying the mean return over the period for 12. Then I calculated the excess returns as difference between the annualized mean return and the benchmark annualized mean return (no risk correction). Annualized standard deviations...
  7. A

    Interaction

    Hi, In your opinion is this a multiplicative qualitative or quantitative interaction?
  8. M

    How to test if gender impacts mortality rates when already considering age

    Hi, I am currently working on a research project where I'm analysing the impact of different factors on mortality. I have the past 10 years of data from a specific hospital and I have graphed the mortality curve by age separately for males and females. I can see that the one curve lies above...
  9. rogojel

    p-values in regression trees

    Hi, I am analyzing some pretty hopeless datasets where the link between the DVs and IVs is quite weak. I observed however that when I take the two groups resulting from the first partition in the tree I can generallly get a nicely low p-value with a t-test . Is this some property of the trees I...
  10. P

    Using pooled data formula or not?

    The question is: Broken arms can be treated with surgery or splints. In a study with 200 patients, half had surgery and half used splints. In the surgery group, 80 patients showed improvement after 2 months whilst 50 who used splints improved. Is surgery more effective than splints for...
  11. S

    Need Help With statistic work. Hypothesis testing

    Question 1 Below are the quarterly returns on investment (in £000s) of two different investment projects, which had the same initial outlay. There is a sample of 16 quarters of returns and your manager has asked you to investigate the relative performance of each project. In particular, your...
  12. L

    Confidence Intervals in a research paper

    Hi, all. I'm writing a paper on concussion data from the NFL Surveillance System, and I want to be able to put the data analysis from the journal article in my own words, but I don't really understand what the researchers are saying. Here's the quote. Can someone please tell me basically what it...
  13. E

    MaxT corrected p value

    Hi all, I am trying to permute data and return a maxT p value to adjust for FWER. I have an example of data: SNP1 p value= 0.02 SNP1 permutation p values = 0.03, 0.03, 0.03, 0.04, 0.04. SNP2 p value =0.03 SNP2 permutation p values = 0.4,0.5,0.5,0.6,0.7 SNP3 p value = 0.3 SNP3 p...
  14. H

    P-Values equal to zero

    Hi, I am running simple OLS regressions on forward and spot price data and have been getting p-values equal to exactly 0 (i.e. not 0.0000000234) for either an x variable and or the intercept. I am not sure how to interpret these and if the interpretation is different between the x variable...
  15. R

    p value relationship to standard error as samples increase?

    Hi all, I would appreciate some help regarding the relationship between the p value and some other elements in my question below. Any help would be appreciated! I've spent about 4 hours researching this, and am still stumped.... How would you calculate the relative size of a p value given...
  16. S

    Help needed for upcoming exam: Chi square

    Okay...I have calculated my chi square with an answer of 8.33. No alpha is specified (so Im assuming it would be stated as 0.05). Degrees of freedom is 1 Question 1: How do I know what the p value is from this information question 2: what does 8.33 mean? does this correspond to a p value...
  17. S

    p-value and estimation of parameters with non linear least squares

    Hi I am performing an estimation of some parameters . I Have the next data: I am using nls.lm() function, and I am trying to fit this data to a logistic distribution. In order to realize this I have defined the next things in R. edad<-datos$Age u_x<-datos$mx...
  18. J

    McNemars Chi squared Test Results

    Hi All, Hope this is the right place. I am QC ing some work of my senior and I am getting some drastically different P values for McNemar's tests. I'm using stata. Here is an example: Base Week 4 0 0 0 1 1 0 3 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 1 1 2 0 0 3 0 3 1 2 1 2...
  19. S

    How do I prove my results are statistically significant or not?

    Sorry in advance, I'm a complete statistics novice! I have a three chemical samples which were prepared in exactly the same way, and when tested have given different results. How would I statistically compare these? I was told by somebody to divide the average by the standard deviation to get...
  20. S

    MANOVA, when independent variable is not multi-level and P value significance varies!

    My research has 4 independent variables and 4 dependent variables. My hypotheses are constructed in such a way that 1 independent variable's effect size is checked on 4 dependent variables. My independent variables are not continuous but they are measured on a 7 item likert scale. And my...