1. A

    Choice of Sample Size for Testing Means

    Here they've made a mistake of using Zα/2 since that will be for a two sided test. This particular question is a one sided test so Zα should have been used. Also they multiplied the population variance by 2. Now, my question is how did they calculate that symbol in the denominator. The symbol...
  2. A

    Test on a single proportion using hypothesis testing

    Do we use z or t distribution? My book only has the formula equaling to z. Some answers that I've seen on forums use t distribution and some uses z distribution. I was confused so I solved a problem using a z distribution and a t distribution separately. Below are my results. I ended up failing...
  3. A

    Paired Observation Hypothesis Testing

    I'm doing a project presentation for applied statistics about hypothesis testing. Me and my partner claimed that the average amount of money that people spend per month on groceries is less than or equal to the average amount spent on dining out. We've used survey monkey (a free online survey...
  4. A

    Choice of sample size for testing means

    Is there a reason why this person altered the original formula by multiplying the population variance by 2?
  5. topsquark

    Testing again

    $\oint _{low}^{high} \left ( \begin{matrix} cos(t) & cost \\ sin(t) & e^{3/2} \end{matrix} \right ) ~ dx + \lim_{x \to \infty} \frac{x^3 - ln(4)}{\sqrt{x^2 - 1}}$ Well, the dollar signs seem to be working. anyone having problems? -Dan
  6. sakonpure6

    Hypothesis Testing: Paired Test

    Hello, I am having great difficulty solving this problem even though I'm following my lecturer's instructions (but apparently incorrectly). If someone can guide me through this I would be greatful. We want to prove that the medicine is effective and we want to prove that: \mu_{\bar{X}} \geq...
  7. A

    Testing Convergence With The Comparison Test

    I got this question wrong on my quiz. My original answer was that the series converges by the comparison test. I revised it and changed the series that I compared it to. After revision, I got that the series diverges. Question.... is my Cn = 1/n correct? This might be a silly question but there...
  8. E

    Hypothesis Testing Z Distribution

    Hello, I need help solving this problem. I have tried using the z - test for a mean formula and get 6.15. I believe I am doing this wrong because I cannot use this number in the standard normal distribution table. I really need help solving this problem. The problem is
  9. sakonpure6

    Hypothesis Testing

    Hello, I am having some difficulty answering part b of this problem. I have set up the p-value of the test and I know that I have to use the student distribution as we are given the average standard deviation (s). However i am stuck calculating the final probability. Also, for part c) which...
  10. Y

    Testing post

    hi, I am new user here, My fist post, so, Keep enjoy.......... :)(Crying)
  11. B

    How do you find the p-value of this (hypothesis testing)

    How do I calculate the p-value and everything? This is the info and what I have so far: ""It is claimed that uni students are more likely to use iphones than the general Australian population. Construct hypotheses and perform a hypothesis test. Show all your working." n = 19. x (people who...
  12. Z

    PLEASE, help me with this attached hypothesis testing results.

    I have a research questionnaire, I collected the results and divided each of the question into H0 (null) and Ha. According to the hypothesis testing, the following results were obtained. image hosting 5mb I googled the significance of the mean, t and p but I would like to consult here what...
  13. E

    Hypothesis testing problem

    Hey all, having an exam coming up and I really struggle with the understanding of these hypothesis tasks. A regression model is used to find the correlation between weightloss and exercise time. where B is an unknown regression parameter, and R is a normally distributed arbitrary variable...
  14. A

    Testing for differences in productivity

    Hi guys, Given a sample dataset like this: Machine Units Produced Time taken A 100 2 A 200 3 B 150 4 B 300 2 A 120 3 I would like to determine if the productivity of Machine A or B is greater. I could calculate the total units produced by A, and divide it by the total time taken by A, and...
  15. M

    Having trouble with finding the p-value and testing proportions.

    I'll start off by saying that I'm not a fan of math, but when I work on it hard enough I eventually conquer it. I'm currently studying for my Stats final (which if I pass, will be my final math class in my college career). So anyway, with these two problems I can solve and work the formula...
  16. T

    Me Testing Latex

    x^2\sqrt{x} \ln{\pi^4} \ln{-\frac{\sqrt{x}}{x^4}} \int{\displaystyle{e^{\frac{\pi}{4}}}} dx \int^4_{2}{e^{\frac{\pi}{4}}} dx \displaystyle{\frac{1}{2}} \\ \frac{1}{2}
  17. M

    Hypothesis testing

    A product has strengths distributed by ~N(40,1.15). A modification has been made to the process in such a way that the mean strength cannot be reduced but it is not certain it will lead to any effective increase in mean strength. Where \bar{x}=40.844; n=9 ii. Carry out an appropriate one-sided...
  18. S

    Testing series problem

    I need to find out which of the following series converge by testing them. I got the first and third one - first one is a geometric series (r>1) with p-series (p>1) , so it diverges. The third one I used integration test and found out that it also diverges. I'm having trouble as to find out how...
  19. W

    Determining Null and Alternative Hypothesis for directional Hypothesis testing

    So I have been reading notes and been doing exercises on the hypothesis testing and now I understand how to implement the systematic steps of the testing. I still don't understand when I have a directional case what my hypotheses should be. I came across the following question Verify a claim...
  20. D

    determine testing hypothesis

    i am having problem with part d , how do we know that the alternative hypothesis is p>0.15 ? what's the clue?