hypothesis testing

Let's say group A (n = 57) is independent from group B (n = 17). The distribution of group A is non-normal (Shapiro-Wilk Test p-val = 0.004) & the distribution of group B is also non-normal (Shapiro-Wilk Test p-val = 0.02). The sample size n = 57 is large enough that I can assume normality for...

n = 72 subjects were randomised to 3 treatment groups: A, B, C, so that n = 26 for Group A, n = 29 for Group B, n = 17 for Group C. Measurements were taken before and after treatment. The differences were calculated between the before & after-treatment observations for the 3 treatment groups...

I have a paired dataset where the before-treatment observations are non-normally distributed (Shapiro-Wilk test p-value = 0.007) and the after-treatment observations are normally distributed (Shapiro-Wilk test p-value = 0.997). What type of test can I use to see if the before-treatment...

Hey everyone, I've been a bit stuck lately on which test to choose or to implement for an assignment. Little bit of context : from a dataframe containing answers of a survey from several hundreds of thousand of people, I needed to ask a scientific question then analyse the data and make...

Hello, I have a test for the thermal performance of a building with a defined uncertainty margin (15%). I want to use it to measure the effects of refurbishments designed to improve thermal performance, but the effect of the refurbishments can be quite small (5-50%). In order to have confidence...

Hi. I need your help in this problem. I need to do some hypothesis testing. The data that I have as below Target is the users that get the voucher, Redeemed is the vouchers that have been redeemed by the users. Based on that data, it appears that 20,000 amount of voucher discount draws high...

Hello, Does anybody know the protocol for when you use two different methods to create confidence intervals and get differing results in the test. I ran a test for a parameter estimation MLE and got different results for my confidence interval. And would like some advice. For example, you...

Hi Suppose that we have two groups that they select N items. For example, in the table below, we have the number of people from each group that have selected each item. items: A B C D E F G H K...

Let X1, X2, . . . , Xn be normal-distributed random variables with unknown mean µ and variance 1 and let X^- =1/n sum_{n=i}^n be their sample mean. Consider the one-sided hypothesis test with hypotheses H0 : µ0 < 0 and H1 : µ0 > 0 with parameters δ = 0.01 and n = 100. What is the smallest µ...

Hi there, I am new in this community. I hope you can help me out. For my master thesis, I have a dataset of 6043 observations. This observations contain the spread differential (delta) of matched securities (I compare one corporate bond with a Green corporate bond of the same issuer) What I...

The sales data follows normal distribution.

Gone through all my notes on this one and raked online but still quite stuck.. ___________________________________________________________________________________________________________________________________________________________ Problem Customers spending on groceries follows a normal...

I'm trying to compare two groups on their ratio between two scores and then investigate the correlation of this ratio for each participant with scores obtained on other tests. What would be an appropriate way of calculating this ratio and what statistical test would I then use to see if there is...

Hi I am doing an event study and my null hypothesis is CAAR=0 and alternative is CAAR does not equal 0 (2 tailed t-test). CAAR is cumulative average abnormal returns. Can a two tailed test be used to give directional conclusions, e.g. if the CAAR value is 1.5% and is statistically significant at...

If you want to test Ho = 0 versus H1≠ 1,with significance level alpha, but instead of testing this directly, you have a strategy: -> X1,...,Xn is a random sample from a N(µ,σ2) distribution with σ2 known (I shall denote the mean of X as X(m)) and we obtain Z = X(m)/(σ/√n) If Z > 0, let H1 : µ >...

im going crazy trying to figure out this problem; please help! 2. Assume that we drew a random sample of 300 women who had recently graduated from USC. All of these women worked full time in 2018. They earned an average salary of $42,167 (s.d. = $26,413). Based on data from the US Census...

Hi everyone. The table above contains two example factories that I would like to test for cointegration using the augmented dickey-fuller test. I intentionally use this short time series because I want to do the calculations by hand. Below you will see my attempt to carry out this procedure and...

Hello! I am not how to tackle my experimental setup in terms of multiple testing correction: I have three performance measures (m1,m2,m3) that I collected from 20 individuals. On top of that I have two measures of some anatomical feature. I correlated every anatomical feature with all the...

I have been facing some doubts regarding the problem given below. Firstly, if this problem is a Z-test or a T-test? Secondly, what should be the standard deviation ? sigma =? Here is my attempted solution, Please help.

I have 10 data points each of which have non-symmetric (i.e., non-Gaussian) errors. That is, if 'a' is the central value (representing the median), then a^{+b}_{-c} means that 'b' is the positive 1-sigma error and 'c' is the negative 1-sigma error. I want to be able to get a representative value...