Learn Before
Describe the steps required to determine statistical significance when testing a correlation coefficient by hand using a critical value table. Your response should outline the parameters needed to find the critical value and the rule used to make a decision about the null hypothesis.
Question: Describe the steps required to determine statistical significance when testing a correlation coefficient by hand using a critical value table. Your response should outline the parameters needed to find the critical value and the rule used to make a decision about the null hypothesis.
Sample answer: To test a correlation coefficient by hand, a researcher first uses the sample size (specifically calculating degrees of freedom, which is ) and a predetermined alpha level, such as , to look up the critical value of in a statistical table. Next, the researcher compares the calculated sample correlation coefficient to this critical value. If the calculated coefficient is more extreme than the critical value, the result is statistically significant, meaning the researcher rejects the null hypothesis and concludes that a relationship exists in the population.
Key points:
- Look up the critical value of in a statistical table using sample size (degrees of freedom) and a predetermined alpha level.
- Compare the calculated sample correlation coefficient to the retrieved critical value.
- Determine if the calculated sample correlation is more extreme than the critical value.
- State that being more extreme means the result is statistically significant, leading to rejecting the null hypothesis and concluding a relationship exists in the population.
Rubric: The response must recall and outline: 1) using sample size/degrees of freedom and a predetermined alpha level to locate the critical value in a table; 2) comparing the calculated sample correlation coefficient to the critical value; 3) applying the decision rule that a calculated value more extreme than the critical value is statistically significant, leading to rejecting the null hypothesis.
0
1
Tags
KPU
Research Methods in Psychology - 4th American Edition @ KPU
Related
When testing a correlation coefficient by hand, what does it mean if the calculated sample correlation coefficient is more extreme than the critical value retrieved from a statistical table?
In psychological research, when testing a correlation coefficient by hand, researchers use critical values to make statistical decisions. Match each scenario or set of parameters with its corresponding role or outcome in this process.
A researcher studying the relationship between noise levels and concentration calculates a Pearson's . The critical value found in a statistical table for their sample size at the level is . In this scenario, the researcher should reject the null hypothesis and conclude that a statistically significant relationship exists in the population.
A psychology researcher is analyzing the relationship between sleep duration and stress levels. After collecting data, they must determine if their results are statistically significant. Arrange the steps of the manual significance testing process in the correct logical order to determine if a relationship exists in the population.
When conducting a test of the correlation coefficient by hand, which two pieces of information are required to locate the appropriate critical value of in a statistical table?
When testing a correlation by hand, the critical value of acts as a threshold; for a result to be statistically significant, the calculated sample correlation must be more extreme than this value.
A psychology researcher calculates a Pearson's for a study exploring the relationship between study hours and exam performance. The statistical table for their sample size indicates a critical value of at the level. Because the calculated value is less extreme than the critical value, the researcher must conclude there is _____ evidence to reject the null hypothesis.
A researcher is preparing to test the correlation coefficient by hand for four different studies. Match each study's sample size to the correct degrees of freedom that should be used when consulting the critical-value table at .
A researcher studies the correlation between exercise frequency and mood in 22 participants and obtains . Consulting a critical-value table at for gives a critical value of .444. Because the sample of .38 is less extreme than the critical value of .444, the -value is _____ .05, and the null hypothesis should be retained.
A peer reviewer is judging whether a researcher correctly concluded statistical significance after testing the correlation coefficient by hand. Place the following evaluation steps in the order the reviewer should perform them to assess the validity of the researcher's conclusion.
Describe the steps required to determine statistical significance when testing a correlation coefficient by hand using a critical value table. Your response should outline the parameters needed to find the critical value and the rule used to make a decision about the null hypothesis.
Explain whether the student should reject or retain the null hypothesis based on this critical value. What does this decision indicate about the population relationship between the variables, and what can be concluded about the -value?
A researcher calculates a Pearson's correlation of with a sample of 22 participants (). The critical value table lists the critical value for 20 degrees of freedom as .444 at the level. Apply the decision rule for critical values of to state whether the researcher can reject the null hypothesis and explain why.