Question

Use SPSS for this Application Exercise:
An educational psychologist hypothesizes that mnemonics can be detrimental to memory. To test this the psychologist designs a study where participants are randomly assigned to a mnemonic method or not. However, before the participants are assigned they are paired for vocabulary knowledge. All the participants are then asked to read a passage from a book. A few days later, the participants are asked to reproduce the passage. Below are the number of correctly recalled words when reproducing the passage. What can the psychologist conclude with α = 0.05?

mnemonic	control
210 349 397 271 332 226 429 348 486 471	223 412 402 285 353 243 443 340 582 490

a) What is the appropriate test statistic?
---Select--- na z-test One-Sample t-test Independent-Samples t-test Related-Samples t-test


c) Input the appropriate value(s) to make a decision about H₀.
(Hint: Make sure to write down the null and alternative hypotheses to help solve the problem.)
p-value =  ; Decision:  ---Select--- Reject H0 Fail to reject H0

d) Using the SPSS results, compute the corresponding effect size(s) and indicate magnitude(s).
If not appropriate, input and/or select "na" below.
d =  ;   ---Select--- na trivial effect small effect medium effect large effect
r² =  ;   ---Select--- na trivial effect small effect medium effect large effect

e) Make an interpretation based on the results.

Participants learning the mnemonic method significantly recalled more correct words than those in the control.Participants learning the mnemonic method significantly recalled less correct words than those in the control.    There was no significant difference in correctly recalling words between the mnemonic method and the control.

Answer 1

a) What is the appropriate test statistic?
Related-Samples t-test


c)
p-value = 0.0279; Decision:  ---Select--- Reject H0

d) Using the SPSS results, compute the corresponding effect size(s) and indicate magnitude(s).
If not appropriate, input and/or select "na" below.
d = 0.8278; large effect
r² = 0.4322; medium effect
e) Make an interpretation based on the results.

Participants learning the mnemonic method significantly recalled less correct words than those in the control.