applied statistics

Hi, I need to produce a probability for a vehicle and a pedestrian meeting along a 1km road. Here is what I know: •1km road •cars take 3 minutes to travel •pedestrians take 12 minutes to travel •30 cars an hour •20 pedestrians an hour The cars and pedestrians may also be grouped or evening...

Hi, I'm using the tolerance interval function in minitab, my sample size is limited to 7 (the parts are expensive blah blah) I've heard to be statistically significant a sample size of 30 is recommended but in practice how low can I go for sample size when using a confidence / tolerance...

Hey all, similar to last year, I'm passing along the tracker for the top 4 statistical model trackers for the season. https://tinyurl.com/ybwyffu3 Good news is that they are all at 100% so far...

I have sets of data in CFU/ml for different sampling sites collected in two different seasons. 1. How do I compare the CFU/ml between sampling sites within one season? 2. How do I compare the CFU/ml in different seasons of the same sampling site? one-way ANOVA?

Hello everyone, I am new to the Data world and am facing a problem which I can’t seem to fix. My task is to analyze why some people cancel their policies and some don’t (find sig. factors) and to estimate the risk of cancelling for different groups. I was thinking of using survival analysis...

Hi everyone, I get in touch with you to check my thinking procedure and my accuracy of stats knowledge which should be now quite low but I try my best even is not my mother language and my top quality topic I study logistics and I have so exam in stat for year 1 I guess after study I...

Hello, I am testing the effect of a new in-store promotion technique (treatment). It is applied during product promotions, as a compliment to regular promo displays, to further improve sales. I have the treatment in only one store but on several products promotions in that store (I have...

Hi there, I would like to ask a couple of basic questions: 1. What is the difference between estimation and hypothesis testing? I mean are they two options for inference? or estimation of the parameters comes first and then we apply the hypothesis testing? 2. How can I determine what is...

general linear mixed model regression equation I'll be moving this to another thread and don't want to create multiple versions. Thanks!

I have an image with the size `5575x9440` and I'm implementing a modified version of the algorithm used in this paper on it, but because the code performance is low right now, I have divided the image to `52628` submatrices of the size `25x40 (1000 pixels)` and my first experiments show that...

I have a question and I'm hoping people can impart some wisdom to my dilemma. My dilemma is lack of data to apply to this problem. The question I'm trying to answer is the probability that any book (in the English language) may be read by any Joe Bloggs. The reason I want to know is because...

I want to rank a set of sellers. Each seller is defined by parameters var1,var2,var3,var4...var20. I want to score each of the sellers. Currently I am calculating score by assigning weights on these parameters(Say 10% to var1, 20 % to var2 and so on), and these weights are determined based on...

I'm working with a large data set looking at climate variables e.g maximum, minimum temperature etc to see whether these could be risk factors for the regional variation for a sheep disease in 5 different regions within a country. The dependent variable is disease count (number of cases)...

Hello As part of survey data. i conducting Mann whitney U test on ordinal data to identify the difference in ranking of dependent variable by independent variable . I have found significant difference in ranking by independent variable categories.. but i don't know the direction of the...

A multilevel model, with one explanatory variable at the individual level (X) and one explanatory variable at the group level (Z): Y_{ij}=\gamma_{00}+\gamma_{10}X_{ij}+\gamma_{01}Z_{j}+\gamma_{11}X_{ij}Z_{j}+u_{0j}+u_{1j}X_{ij}+e_{ij} correlation between u_{0j} and u_{1j} is 0 . In this...

I am having some trouble to understand the notation of variance of residuals in multilevel modeling . In this paper "Sufficient Sample Sizes for Multilevel Modeling" , in p.87 below equation (3) , they mentioned " the variance of residual errors u_{0j} and u_{1j} is specified as...

The post is little bit lengthy , but it will give you thorough information and you can run the code easily . Trust me , I believe the answer is really very basic and not lengthy at all . I want to calculate relative bias of estimates of multilevel logistic model with one explanatory...

I am a student of statistics discipline. I have to conduct a project which i can apply in society or nation. My preferable topics are agricultural/technological/environmental statistics. But i am not understanding how can i specialize my topic, make it applicable and can have an ample online...

I am working on a problem where we elicit medical residents perceptions regarding the importance of specific core medical competencies (professionalism, collaboration, medical expertise, etc.) on a 5 point Likert scale. For example, "In your current residency role how important is...

Hello everyone, I've always been into statistics but I never studied it, other than a little in high school. I've decided I want to try to get a job in the 'big data' field, or any job where I would analyze data in ways that enable business decisions, for example being the guy at Facebook who...