COMMENTS

  1. Hypothesis Test: Difference in Means

    The first step is to state the null hypothesis and an alternative hypothesis. Null hypothesis: μ 1 - μ 2 = 0. Alternative hypothesis: μ 1 - μ 2 ≠ 0. Note that these hypotheses constitute a two-tailed test. The null hypothesis will be rejected if the difference between sample means is too big or if it is too small.

  2. 10.29: Hypothesis Test for a Difference in Two Population Means (1 of 2

    Step 1: Determine the hypotheses. The hypotheses for a difference in two population means are similar to those for a difference in two population proportions. The null hypothesis, H 0, is again a statement of "no effect" or "no difference.". H 0: μ 1 - μ 2 = 0, which is the same as H 0: μ 1 = μ 2. The alternative hypothesis, H a ...

  3. Mean Difference / Difference in Means (MD)

    The formula for the mean of the sampling distribution of the difference between means is: μm1-m2 = μ1 - μ2. For example, let's say the mean score on a depression test for a group of 100 middle-aged men is 35 and for 100 middle-aged women it is 25. If you took a large number of samples from both these groups and calculated the mean ...

  4. 10.5: Difference of Two Means

    Hypothesis tests Based on a Difference in Means A data set called baby smoke represents a random sample of 150 cases of mothers and their newborns in North Carolina over a year. Four cases from this data set are represented in Table \(\PageIndex{2}\).

  5. 12.3: Difference between Two Means

    Figure 12.3.1 shows that the probability value for a two-tailed test is 0.0164. The two-tailed test is used when the null hypothesis can be rejected regardless of the direction of the effect. As shown in Figure 12.3.1, it is the probability of a t < − 2.533 or a t > 2.533. Figure 12.3.1: The two-tailed probability.

  6. Two-sample t test for difference of means

    And let's assume that we are working with a significance level of 0.05. So pause the video, and conduct the two sample T test here, to see whether there's evidence that the sizes of tomato plants differ between the fields. Alright, now let's work through this together. So like always, let's first construct our null hypothesis.

  7. Hypothesis test for difference of means (video)

    Say you test your sample the way Sal does it, and realize that the probability of you getting that sample was 1%. Normally, you would reject the null hypothesis. But say the null hypothesis was indeed correct. This means you just happened to choose a lot samples from the far left or far right of the population mean.

  8. Hypothesis Test for a Difference in Two Population Means (1 of 2

    Step 1: Determine the hypotheses. The hypotheses for a difference in two population means are similar to those for a difference in two population proportions. The null hypothesis, H 0, is again a statement of "no effect" or "no difference.". H 0: μ 1 - μ 2 = 0, which is the same as H 0: μ 1 = μ 2. The alternative hypothesis, H a ...

  9. 9.2: Comparing Two Independent Population Means (Hypothesis test)

    The means for the two populations are thought to be the same. Is there a difference in the means? Test at the 5% level of significance. Table \(\PageIndex{2}\) Sample Size Sample Mean Sample Standard Deviation; Population A: 25: 5: 1: ... Comparing Two Independent Population Means (Hypothesis test) is shared under a CC BY 4.0 license and was ...

  10. Writing hypotheses to test the difference of means

    Writing hypotheses to test the difference of means. An exercise scientist wanted to test the effectiveness of a new program designed to increase the flexibility of senior citizens. They recruited participants and rated their flexibility according to a standard scale before starting the program. The participants all went through the program and ...

  11. 7.3

    Hypothesis Test for the Difference of Paired Means, \(\mu_d\) In this section, we will develop the hypothesis test for the mean difference for paired samples. As we learned in the previous section, if we consider the difference rather than the two samples, then we are back in the one-sample mean scenario.

  12. Hypothesis test for difference of means

    Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/math/statistics-probability/signifi...

  13. Z Test: Uses, Formula & Examples

    Two-Sample Z Test Hypotheses. Null hypothesis (H 0): Two population means are equal (µ 1 = µ 2). Alternative hypothesis (H A): Two population means are not equal (µ 1 ≠ µ 2). Again, when the p-value is less than or equal to your significance level, reject the null hypothesis. The difference between the two means is statistically significant.

  14. Hypothesis Test for a Mean

    Solution: The solution to this problem takes four steps: (1) state the hypotheses, (2) formulate an analysis plan, (3) analyze sample data, and (4) interpret results. We work through those steps below: State the hypotheses. The first step is to state the null hypothesis and an alternative hypothesis.

  15. Hypothesis Testing

    This statistics video explains how to perform hypothesis testing with two sample means using the t-test with the student's t-distribution and the z-test with...

  16. Hypothesis Testing for Means & Proportions

    The risk difference is analogous to the difference in means when the outcome is continuous. Here the parameter of interest is the difference in proportions in the population, RD = p 1-p 2 and the null value for the risk difference is zero. In a test of hypothesis for the risk difference, the null hypothesis is always H 0: RD = 0.

  17. Hypothesis Test for a Difference in Two Population Means (1 of 2)

    Step 1: Determine the hypotheses. The hypotheses for a difference in two population means are similar to those for a difference in two population proportions. The null hypothesis, H 0, is again a statement of "no effect" or "no difference.". H 0: μ 1 - μ 2 = 0, which is the same as H 0: μ 1 = μ 2. The alternative hypothesis, H a ...

  18. An Introduction to t Tests

    Revised on June 22, 2023. A t test is a statistical test that is used to compare the means of two groups. It is often used in hypothesis testing to determine whether a process or treatment actually has an effect on the population of interest, or whether two groups are different from one another. t test example.

  19. Making conclusions about the difference of means

    Choose 1 answer: The P-value is less than α = 0.05 , and she should conclude that there is a difference between the means. A. The P-value is less than α = 0.05 , and she should conclude that there is a difference between the means. The P-value is less than α = 0.05 , and she cannot conclude that there is a difference between the means.

  20. Hypothesis Test: Difference Between Paired Means

    The first set of hypotheses (Set 1) is an example of a two-tailed test, since an extreme value on either side of the sampling distribution would cause a researcher to reject the null hypothesis. The other two sets of hypotheses (Sets 2 and 3) are one-tailed tests, since an extreme value on only one side of the sampling distribution would cause a researcher to reject the null hypothesis.

  21. Hypothesis Testing

    Step 5: Present your findings. The results of hypothesis testing will be presented in the results and discussion sections of your research paper, dissertation or thesis.. In the results section you should give a brief summary of the data and a summary of the results of your statistical test (for example, the estimated difference between group means and associated p-value).

  22. T-test and Hypothesis Testing (Explained Simply)

    Student's t-tests are commonly used in inferential statistics for testing a hypothesis on the basis of a difference between sample means. However, people often misinterpret the results of t-tests, which leads to false research findings and a lack of reproducibility of studies. This problem exists not only among students.

  23. Difference in Means Hypothesis Test Calculator

    A hypothesis test for the difference in means is sometimes known as a two sample mean t-test because of the use of a t-score in analyzing results. Interpret Your Results. The conclusion of a hypothesis test for the difference in means is always either: Reject the null hypothesis; Do not reject the null hypothesis

  24. Hypothesis Test Calculator

    Calculation Example: There are six steps you would follow in hypothesis testing: Formulate the null and alternative hypotheses in three different ways: H0: θ = θ0 versus H1: θ ≠ θ0. H0: θ ≤ θ0 versus H1: θ > θ0. H0: θ ≥ θ0 versus H1: θ < θ0.