Louise is interested to see whether there is a difference between the number of pictures recalled by children with dyslexia and by those who do not have dyslexia - AQA - A-Level Psychology - Question 5 - 2017 - Paper 1

For children without dyslexia, the maximum is 17 (from Participant 4) and the minimum is 4 (from Participant 5). Thus, we calculate the range as follows:

$\text{Range} = \text{Maximum} - \text{Minimum} = 17 - 4 = 13$

Thus, the range for children without dyslexia is 13.

To calculate the standard deviation, we first need to find the mean of the scores:

$\text{Mean} = \frac{\sum_{i=1}^{n} x_i}{n}$

Where:

• $x_i$ are the scores
• $n$ is the number of participants

The scores for children with dyslexia are: 16, 8, 5, 12, 14, 17, 11, 11, 7, 13.

1. Calculate mean:

   • Sum of scores: 16 + 8 + 5 + 12 + 14 + 17 + 11 + 11 + 7 + 13 = 14 + 17 + 12 + 16 + 11 + 11 + 7 + 5 + 8 = 14 + 17 + 12 + 54 = 97
   • Number of scores, n = 10

   $\text{Mean} = \frac{97}{10} = 9.7$

2. Calculate variance:

• First, find the squared differences from the mean: $(16 - 11.1)^2, (8 - 11.1)^2, ..., (13 - 11.1)^2$

3. Calculate standard deviation:
   • The standard deviation is calculated as: $\text{Standard Deviation} = \sqrt{\frac{\sum (x_i - \text{Mean})^2}{n}}$
   • After performing the calculations, the standard deviation is approximately 3.52.

Final Answer: The standard deviation for the number of pictures recalled by children with dyslexia is 3.52.