Research Methods

Practice Questions Identifying the Statistical Test

01 A researcher is comparing the height of 20 participants with their IQ levels to investigate if there is a link. The hypothesis was that there will be a positive correlation. Which statistical test should they use and why? [3 marks]

And using the table in the textbook, identify (i) the critical value they should use [1 mark] (ii) if the study found statistically significant results, assuming their test returned a score of 0.410 [1 marks]

02 A researcher wants to investigate happiness scores by self-report out of 10 correlated with their shoe size. Which statistical test should they use and why? [3 marks]

03 A study was conducted where 20 participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and three days later sat in a car for 30 minutes with no headphones in and then recorded their happiness out of 10. Which statistical test should the psychologist use and why? [4 marks]

04 A study was conducted where participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and another group of participants sat in a car for 30 minutes with no headphones in and then recorded their happiness out of 10. Which statistical test should the psychologist use and why? [4 marks]

05 A study was conducted where 7 participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and a comparable matched group of 7 participants sat in a car for 30 minutes with no headphones in and then recorded their happiness scores out of 10. Their hypothesis was that there will be a difference in the happiness ratings of participants when they have worn headphones in a car for 30 minutes or they have not work headphones in a car for 30 minutes. Which statistical test should the psychologist use and why? [4 marks]

And using the table in the textbook, identify (i) the critical value they should use [1 mark] (ii) if the study found statistically significant results, assuming their test returned a score of 20 [1 marks]

06 A researcher conducted a study whereby 10 participants had to sit in a white waiting room for 30 minutes and then write down their favourite colour. Three days later, the same 10 participants sat in a purple waiting room for 30 minutes and then write down their favourite colour. Which statistical test should the psychologist use and why? [3 marks] 4 participants kept their favourite colour the same, 3 changed to purple and 6 changed from purple. Identify the calculated value of the test. Justify your answer. [2 marks] The critical value for this test was 4. Did the psychologist find a significant result? Yes or no. [1 mark]

Practice Questions Identifying the Statistical Test ANSWER SHEET

01 A researcher is comparing the height of 20 participants with their IQ levels to investigate if there is a link. The hypothesis was that there will be a positive correlation. Which statistical test should they use and why? [3 marks]

Pearson s Rank correlation, interval level data x2 therefore parametric

And using the table in the textbook, identify (i) the critical value they should use [1 mark] (ii) if the study found statistically significant results, assuming their test returned a score of 0.410 [1 marks]

Critical value of .360. They found .410. Therefore the result is significant. Rule of R (higher if R).

02 A researcher wants to investigate happiness scores by self-report out of 10 correlated with their shoe size. Which statistical test should they use and why? [3 marks]

Ordinal data so non-parametric. Correlation. Therefore Spearman s Rho.

03 A study was conducted where 20 participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and three days later sat in a car for 30 minutes with no headphones in and then recorded their happiness out of 10. Which statistical test should the psychologist use and why? [4 marks]

Repeated measures test. Ordinal data, so non-parametric. Not a correlation due to IV. Therefore Wilcoxon.

04 A study was conducted where 20 participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and another group of participants sat in a car for 30 minutes with no headphones in and then recorded their happiness out of 10. Which statistical test should the psychologist use and why? [4 marks]

Independent groups. Ordinal data, so non-parametric. Not a correlation. So Mann-Whitney U.

05 A study was conducted where 7 participants sat in a car for 30 minutes with headphones in and then recorded their happiness out of 10 and a comparable matched group of 7 participants sat in a car for 30 minutes with no headphones in and then recorded their happiness scores out of 10. Their hypothesis was that there will be a difference in the happiness ratings of participants when they have worn headphones in a car for 30 minutes or they have not work headphones in a car for 30 minutes. Which statistical test should the psychologist use and why? [4 marks]

Matched pairs test is NOT independent groups. Ordinal data, so non-parametric. Not a correlation due to IV. Therefore Wilcoxon.

And using the table in the textbook, identify (i) the critical value they should use [1 mark] (ii) if the study found statistically significant results, assuming their test returned a score of 20 [1 marks]

Critical value of 21. Actual value of 20 is lower, so significant (rule of R).

06 A researcher conducted a study whereby 10 participants had to sit in a white waiting room for 30 minutes and then write down their favourite colour. Three days later, the same 10 participants sat in a purple waiting room for 30 minutes and then write down their favourite colour. Which statistical test should the psychologist use and why? [3 marks] 4 participants kept their favourite colour the same, 3 changed to purple and 6 changed from purple. Identify the calculated value of the test. Justify your answer. [2 marks] The critical value for this test was 4. Did the psychologist find a significant result? Yes or no. [1 mark]

Repeated measures test, experiment. Nominal data so non-parametric. Therefore Sign Test. S=3 because least frequent result value. Critical test of 4, therefore results were significant (rule of R).