1)The teacher's personal opinion cannot be accepted as scientific evidence because she is

making a generalisation from just her own class. She has not used the scientific method to

come to her conclusions about breakfast and reading abilities and she should have

operationalised her criteria when working out if her pupils had proper nutrition in the

morning rather than using loose vocabulary such as 'decent breakfast'.

2) The researcher could of put all names of the 400 students on pieces of paper into one

container. He could of then selected 100 names from the container collecting his random

sample of his access group. To reduce the risk of bias the researcher should use the same

size paper for each name and have the paper folded in a way so he cannot possibly know

which names he is picking.

3) Limitations of using random sampling in this study could come from the fact that the sample

may not be truly representative. All names selected could come from only a few of the

schools or he may not get an equal representation from each gender. The sample he does

get at the end may be bias as not all parents will agree to their child being used in a study so

a limitation would be that there are difficulties in getting a sample through this method.

4) It is important to operationalise the independent and the dependent variables in this study

because the psychologist needs to have clear criteria for what exactly a 'decent breakfast' is.

There are many ways in which the psychologist could operationalise the variables such as

specifying what a good breakfast consists of and he could provide a reading test that the

pupils can take.

5) The Mann-Whitney U test was used because the study used an independent groups design

and it was a test of difference.

6) It would of been difficult to use a matched