# statistics

1. ### drawing up a mediation model with 2 predictors and 1 mediator

Hello all, I was hoping someone could help my understand where a certain value comes from in my data output (using SPSS). I have performed a hierarchical multiple linear regression and the used PROCESS to find that my model has 2 predictor variables which both go through the 1 mediator variable...
2. ### Generalized linear mixed model: Type III significant but multiple comparisons not significant

Hi guys I am running a glmm model for my data, the Type III tests of fixed effects is showing that there is a significant effect of treatment but when i run the multiple comparisons, non of the treatment levels are significant. What causes this confusion? Is my model not right maybe? Regards...
3. ### How to show statistical equivalence between groups of data?

I'm trying to determine if these two groups of data are equivalent. How do I show that mathematically? I have conducted an experiment in which three samples were each measured at two time points as shown in the image. I would like to compare these data and demonstrate (with some sort of...
4. ### "Number of Persons” Vs “Number of Person-years” in a Stationary Population

I have learnt that the life table function nLx is the number of "person-years" lived by the cohort between ages x and x+n. But for stationary population, nLx is defined as the number of persons in the population who at any moment are living within the age interval (x, x+n). I don't...
5. ### Help with choosing a method

Hi, I am currently conducting a short research paper for my university course and am struggling to determine which statistical analysis would be appropriate for the data I have collected. I surveyed two groups of 50 people: 50 x people aged 40 and over 50 x people aged under 40 My hypothesis...
6. ### Standardising a score of values

Hello, I am working on developing on a standardised score from a number of scores. The values will be ranging from large to small of each score and I am trying to develop a way of proportionally measuring different data sets. I have something at the moment which is: (x1/largest x in dataset1)...
7. ### Sum of two normal distributions

Hello, I'm doing data analysis research and currently I'm trying to fit the simple model to a data sample. From physical speculations I know that the distribution should be a sum of two normal distributions with different parameters (mean, width, area). I fitted my data with the model and it...
8. ### Sampling Distribution Problem

Roll a dice five times. Record the results in Sample 1. Repeat the experiment for Sample 2, 3, and 4. In a live classroom setting, actual survey data is used. In this knowledge check online environment, please use the following data: Sample 1 Sample 2 Sample 3 Sample 4 2 4...
9. ### Analysis for difference in variances between group?

I have data for 100 different biomarkers. Each biomarker has data for 4 groups (A,B,C,D) with ~2000 observations in each group. I've read a lot about ANOVA but I'm not looking for a difference in means, only a difference in variances between the 4 groups, for each biomarker. I know there is the...
10. ### Which Statistical test is it?

Any chance anyone knows the answer to this? I know it's not paired t-test but don't know which of the others it is A hotel manager would like to test whether the average time taken for customers to complete the hotel's online booking form is less than 5 minutes. She selects a sample of 40...
11. ### The proportion of twitter followers of handle X also following Y

OK, someone recently asked me what the probability that followers of Twitter handle X are also followers of Twitter handle Y. I used some R code (using the twitteR package) to get 47,000 followers from X and 61,000 followers of Y (the two handles have a LOT of followers). I created a vector and...
12. ### joint probability

I am not really sure how to calculate question C. Can anyone help me out? Thanks in advance!
13. ### How to find the probability of a sampling error made in estimating the population mean?

Alright, I have been working on my statistics assignment since Monday and I only have two questions left, dealing with the probability of a sampling error. Unfortunately, I cannot find anything in my notes and only a brief example in my textbook that does not explain the concepts behind the...
14. ### Probability question

The govt. of ontario decided it would try to raise money by installing photo radar cameras on the 401 highway acros the top of Toronto. The camera would be set to record the speed of those travelling more that 135 km/h and send them a ticket for \$200. It would only run the program between the...
15. ### multi label problem

Hi everyone, I'm currently working on my master dissertation. It is about the adoption of new products (COCA COLA PRODUCS). These are 26 new products. I need to determine which makes a foodservice business adopt the new products. I also have variables, such as environment of the business...
16. ### Financial Statistics

I am looking to create some useful statistics for the company I work for. I posted another question with a similar format for a specific regression analysis question, however, this question is different. I have a dataset that includes company name, company type, service provided, charge for the...
17. ### one way ANOVA or paired t test?

Apologies if this is a basic question, but my stats is very rusty these days! Background: I'm looking at a procedure that automates FISH analysis in a genetics diagnostics laboratory. I am currently running 7 patients that are negative controls (known normal patients) on the automated system to...
18. ### Data Science Consulting Jobs

Hi all, STATWORX is a data science and statistics consulting company, located in Frankfurt Germany. Currently, we are looking for entry level and experienced data scientists. You can find our job offerings in our data science consulting page (German language). Feel free to apply to any of our...
19. ### Need help with a theoretical question

Here is the question: How does the return distribution relate to the normal distribution if the return horizon becomes longer? :yup:
20. ### Books for Stats

Hi All I am doing the MBA program. We have stats in our syllabus. I have strong mathematics background, however, I am not finding enough books to practice stats from. The questions we get aren't direct. We always get questions with a data set, which we solve using Excel/Data...