Question 7
Previous research studies showed that the mean learning performance of college students is 64 out of 100 when they are presented with static illustrations along with textual information. A researcher is interested in whether using animations instead of static illustrations would increase learning performance. She collects data from 31 college students. The dataset can be found in the Excel file.
Based on the information above, which of the following is the effect size (d)?
- A. 2.9576
- B. 1.1667
- C. 2.009
- D. 1.2443
- E. 2.9824
What is effect size and how to find the effect size:
The effect size d, often referred to as Cohen's d, is calculated to measure the difference between two means relative to the variability of the data. It is commonly used in experiments to determine the strength of the treatment effect.
Here's how you calculate d:
Formula:
Steps to calculate d:
- Calculate the mean of each group:
- Mean of the experimental group (using animations).
- Mean of the control group (using static illustrations).
- Calculate the standard deviation for each group:
- Standard deviation of the experimental group.
- Standard deviation of the control group.
- Compute the pooled standard deviation: The pooled standard deviation accounts for the variances within both groups.
