PSYC FPX 4700 Assessment 3 Hypothesis, Effect Size, Power, and t Tests Problem Set 3.2: Effect Size and Power Criterion: Explain effect size and power.
Instructions: Read each of the three scenarios below and respond to the questions.
A test designed by two researchers measures the efficacy of drug treatment. According to Researcher A, the effect size for the male population is d = 0.36; Scientist B confirms that the effect size for the female population is d = 0.20. If all other factors are equal, which researcher has a greater ability to identify an effect? Explain.
Researcher A is likely to have a higher ability to identify the effect due to the larger disparity between the null and alternative means. This is because the test is more powerful with a larger effect size.
Two researchers conduct a study on the levels of marital satisfaction among military families. Researcher A collects a sample of 22 married couples (n = 22), while Researcher B gathers a sample of 40 married couples (n = 40). All other factors being equal, which researcher has a greater ability to detect an effect? Explain.
Researcher B has a greater ability to detect an effect due to the larger sample size, as power is positively correlated with sample size.
Two researchers conduct a study on standardized test performance among high school students in two nearby communities. Researcher A tests performance in the northern community, where the standard deviation of scores is 110 (σ); Researcher B tests performance in the southern community, where the standard deviation of scores is 60 (σ). If all other factors are equal, which researcher has a greater ability to identify an effect? Explain.
Researcher B has a greater ability to detect an effect due to the smaller standard deviation, which typically indicates less variability in scores and thus a clearer signal of any potential effect.
Problem Set 3.3: Hypothesis, Direction, and Population Mean
Criterion: Explain the relationship between hypothesis, tests, and population mean.
Instructions: Read the following and answer the questions.
Testing hypotheses in a directional or nondirectional manner. A commentary on the appropriate use of one-tailed and two-tailed tests in behavioral research was provided by Cho and Abe (2013). To test a research hypothesis that males self-disclose more than females, they discussed the following hypothetical null and alternative hypotheses:
H0: Males = Females
H1: Males > Females
Which type of test is used to test these hypotheses? A directional or nondirectional test?
Since the alternative hypothesis (H1) is stated in a way that specifies a single direction of effect—indicating that males engage in greater self-disclosure than females—the hypothesis is formulated as a directional test.
Do these hypotheses encompass all population mean possibilities? Explain.
The provided hypotheses account for all potential outcomes regarding the population mean. Since male means can be equal to, lower than, or higher than female means, the hypotheses cover every possible scenario for the population mean.
Problem Set 3.4: Hypothesis, Direction, and Population Mean
Criterion: Explain decisions for p values.
Instructions: Review the following and answer the brief.
The value of a p value. In a straightforward commentary on the use of significance testing, Lambdin (2012) explained, “If a p < .05 result is ‘significant,’ a p = .067 result is not ‘insignificantly significant’” (p. 76).
Identify the two options available to a researcher and explain what the author is referring to.
A researcher will reject the null hypothesis if the p-value is less than 0.05, while they will fail to reject the null hypothesis and accept the alternative hypothesis if the p-value is greater than 0.05.
t Tests
Problem Set 3.5: One-Sample t test in JASP
Criterion: Calculate a one-sample t test in JASP.
Data: Utilize the minutesreading.jasp dataset. This dataset contains a sample of reading times (in minutes) for Riverbend City online news readers. Riverbend City online news claims that it is read longer than public news, which has a mean reading time of 8 minutes per week.
Instructions: Complete the steps below.
The minutesreading.jasp dataset can be downloaded. To open the dataset in JASP, double-click the icon.
- Click on T-tests in the Toolbar. Select One-sample t-test from the Classical menu that appears.
- Select Time and click the Arrow to move it to the Variables box.
- Ensure the box is c