statisitcs

  1. P

    Should IRRs and HRs always be equal?

    I am running an analysis in a large population registry where individuals enter and leave the dataset at different time points. When i estimated the IRR between two distinct groups and a health outcome, and then a HR, I am finding a small difference (IRR 2.18, HR 2.01). Shouldn't they have...
  2. U

    Concept of Stationary Population in Demography.

    The definition of stationary population is: "The stationary population is a model without immigration or emigration in which the same age-specific probabilities of death apply continuously and in which there are the same number of births and deaths each year." Can anyone please explain me...
  3. H

    Get quartiles and a half of the data

    The following table shows a frequency distribution of the scores obtained in a test. Punctuation (3, 4] (4, 5] (5, 6] (6, 7] (7, 8] (8, 9] (9, 10] Number of participants 2 4 10 20 40 35 9 (a) The highest score reached by the bottom...
  4. C

    Empirical Survivor Function (esf)

    From page 26, chapter 2 of the reference "Tableman, M., & Kim, J. S. (2003). Survival analysis using S: analysis of time-to-event data. CRC press", I have found the definition of the empirical survivor function (esf) is S(t) = (number of individuals > t)/n . But from page 80, chapter 3 of...
  5. U

    Relative Efficiency

    Consider the following equation: T_i = A_i + Z_i * B_i,i=1,2...,6. Suppose for all i(i=1,2,...,6) data generation of A_i and B_i are exactly same for two methods. The two methods differ only in generating data of Z_i. For method 1, Z_i is generated from Bernoulli distribution with...
  6. W

    Comparing habitat use across two different locations - mann whitney U?

    Hi, I'm really stuck with what test to use with my data. I have data on habitat use of 6 different habitat types across 2 locations and I'm unsure what test is most suitable. I thought initially mann whitney U but this doesn't seem to be working for me. I've attached the table below so you...
  7. A

    Interpretation of a certain observation

    I have some identities that are distributed in a 2D space. Each identity has the properties X, Y, latitude, and longitude. Each dataset on average has 75 of these identities. For a particular dataset, when I plot X as a function of Y, I get no correlation. When I group the identities (say into...
  8. L

    Help for student research paper

    Dear Talk Stats'ers, Through our research we have some nominal scaled independent value's (a group of people, ex. Openness to Change) and interval/ratio scaled dependent value's (score on different sensory properties). Now we need to find out which sensory properties are affecting a specific...
  9. E

    Quasi-experiments and variable manipulation

    Hello, I am new here so forgive me if I seem amateur, After doing a lot of research and discussion with other students I have continued to find conflicting information about whether the manipulation of variables is or is not required in order for it to be a quasi experimental design. Can...
  10. A

    Business major looking in the MS Statistics

    Hello, So I'm about to finish a my BBA and am looking into working with data analytics. There are plenty of great business analytics programs out there that I'm eligible for, but I think I'd like to expand my opportunities (i.e. if I ever want to go into research much later on through a PhD...
  11. L

    question about change in period

    Hello guys:) I wonder whether you can help me. I do not know which analysis i can use. My aim is to prove or not the following hypothesis: The percentage amount of impairment ( impairment/total assets) has grown during 2012-2014 years. My data will consist of percentage amount of...
  12. I

    Calculating mean for Date values using range and counts

    Hi, For the purpose of calculating the average number of days between 2 transactions, I was always 1. subtracting the greater dates from the lesser dates (as in the LEAD functions available in different software and statistical packages) 2. adding the result of step 1 3. dividing the...
  13. N

    Identifying numeric algorithm for data analysis

    I want to Study and analyzing of algorithms and make predictions on key data for different sports. There are 3 #'s. 1. the screens predicted number 2. our predicted number 3. the outcome number Prediction works like, #2 predicts the right side of #1 with #3 at a rate of 57% or higher...
  14. A

    sapply function in R help

    I have read two .csv files and did some editing. >a1<-read.csv("2013.csv",header=T, na.strings = c("NULL","PrivacySuppressed")) >a2<-a1[,441,drop=F] >a3<-a1[,-441,drop=F] >a4<-cbind(a1,a2) >a4<-a4[, colSums(is.na(a4)) != nrow(a4)] > mode(a4) >[1] "list" I need the a4 to be...