statistical test

Hi, Soon I will be performing an experiment where I must grow 4 different plant species under 4 different stressors, each stressor containing 4 levels of 'severity' of the stressor or in other words a difference in concentration. Growth of the plants will be measured over 22 time points, but...

The sales data follows normal distribution.

Dear All, I am a surgeon trying to investigate how indications for a device has changed over 5 years. I have the following data set for patients; I want to find out for each indication if there is a trend or a statistically significant relationship over the years. What is the best statistical...

HI, I'm struggling to find out which statistical test is most appropriate to analyze the impact of negative interest rates on profitability; Data collected: Sample - 30 Banks Yearly data for each variable from year end 2007 to year end 2017 - 10 years Variables I'm considering are...

Can you pleaase kindly help me with my scholarly article? (I spent lots of time by solving this issue - to no avail): I observed whether (and to what extent) the 52 SAME companies use their capacities across the years 2006, 2010, 2014, 2018. ----- Here are the counts of companies (categorized by...

Hi, We are commonly have a problem where we do A/B test over a population of users but it seems like population sometimes differ even before the tests starts. So let's say I have over multiple days the KPI per group (control & test), how would you test for the treatment significance? This is...

Hello everyone I'm carrying out a research which tries to analyse factors affecting coffee consumption behavior, there are 7 independent variables on hand and 1 dependent variable which is coffee consumption behavior Is Multiple regression analysis can be used while there is relation among...

Hello All, I am currently analysing my experimental data on postharvest storage of pears. Lets say that I had 2 fcators (light treatment and cold storage duration). First, light treatment with 3 level of lighting intensity (0, 30 and 50 micromole per second). I grew my pears in this 3...

I am doing an investigation about the effect of altitude on the density of two tree species. Would it be possible to use the one-way ANOVA test to determine whether there is a statistically significant relationship between the density of beech and oak trees and altitude? If not, can low...

Dear friends, I'm now working on the recommendation system to recommend football match lottery to the users. The users may choose a match to bet arbitrary amount of money, e.g. $2, $4, or even $20,000. I want to compare if two recommendation algorithms are different (or if one outperforms...

Hi all, I just had a test with the following question, of which I doubt the 'correct' answer: Taking a level of significance of 5% in a hypothesis test and not rejecting the null hypothesis, is the same as saying: A. We are 95% confident that the results have occurred by chance B. We are 95%...

I am working on my independent action research project and need help figuring out what statistical test to use. I am looking at how my students' waste management knowledge and behaviors change pre- and post- survey. Usually, when I have done something like this, I run a paired t-test since...

I have data from three populations, 2 observations each populations (opinion poll data from different countries). I am trying to find out if any changes in opinion on the issue i am investigating are statistically significant. So, for one topic In 2010, Group 1 answered 20% yes, Group 2...

Hi Everyone, Pretty new to stats and want to make sure that I am running the right stats. I have means (measured in months) from multiple sites. My supervisor asked me to determine whether there are any site specific significant differences in these means. I am thinking that I should run a...

Hi, I need statistical test which would tell me which percent of variability in dependent variable is from given independent set of variables and which of unknown ones. Example: Model: Y = Model (X1, X2, X3, ....) Measurements of Y, X1 and X2 are given. I need test which tells me the portion...

Dear all, For my thesis, I would like to conduct a statistical test in SPSS to explain trade between the United States and 12 different regions, based on a couple of independent variables (both ratio and binary). I have seen that STATA is the best way to do this, however I have no experience...

I've collected data on the number of individuals of seven species at three different sites and want to test if there is a statistically significant difference between the three sites. The numbers are too small to use Chi square and I cannot make a 2x2 table for the Fisher's exact test. Are there...

I am developing different algorithms for a class of optimization problems. I have several problem instances in this class (some from real applications, some randomly generated), which do not differ in terms of structure, but in terms of data. I would like to compare the performance of my...

Hi! I have a single sample and asked them to think about their best and worst experiences in a class project. They answered identical sets of questions when considering the best project and again when considering the worst project. Here are the question examples: When thinking about your...

Hi, we just had an interesting discussion about the chi-squared test, that could be generalized. I think the core of the discussion was whether one should prefer a simple statistical test or a statistical model - e.g. a chi-squared test vs. a logistic regression. Given that in practice one is...