# statisitcs

1. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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. ### 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) > "list" I need the a4 to be...