hypothesis testing

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...

Hi, this is my first post here, hope that I'm doing this correctly! I'm taking a statistics course for my master's where we need to do some hypothesis testing with a pre-defined data set using R. I am unsure about what the most appropriate statistical test to use is, so I was wondering if...

I have a few questions, but first let me give you some necessary background of the experiment and the underlying questions. Basically, the design is as follows: 3 independent repeated experiments across different days using different stocks of a cell lineage (clones); One factor called...

So I have a 4 point likert-type scale with approximately 20 questions. I have categorized each item to be either agree or disagree. I mainly did this because the previous person who used this scale did this. However, that person only displayed frequency data for it and did not run any tests for...

Hello, I'm interpreting data at the moment from my Pearson Correlation analysis for different groups of respondents. One of my group only consists out of two respondents. As a result for the one Pearson correlation analysis I get p=-1 and for the other p=1 as well as both times (Sig 2tailed)...

Hi New to the site - I've managed 11 out of 13 questions for my final set of Master Black Belt homework but now stuck! Can anyone offer an explanation to this question and how it could be answered in minitab? I've had a very extensive look online and found multiple solutions but cannot work...

We had to do an experiment in my research methods class. Me and my group did an experiment where we tested if participants remembered words better with or without pictures that match the words. So now we have two sets of data: One set with the number of words they remembered and one set with the...

A sales compnay wants to forecast its sales . There are 2 samples with n1 =30 and n2=30 .Since its a small sample I did paired t- Test in excel . I got critical T value is greater than the calculated t value. Im ok till this part. Now in order for the sales company to break even, the average...

Suppouse that we have a dataframe called dataWork with data from a database. There are several variables and 2 of them are: - Delay: time (minutes) to get to work (could be empty) - Nocturnal: 0 (work by day) 1 (work by night) we want to know the relation between delay and nocturnal. So...

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...

Hi there, Adding to my previous questions: 1. Why do I need goodness of fit test? I mean when I get a set of data should I always suggest a distribution for it and then do test the goodness of fit for this hypothesis? or it comes in sequence of :1.estimation 2.goodness of fit 3.hypothesis...