Question

The article "Yes that Miley Cyrus Biography Helps Learning" (The Globe and Mail, August 5,2010 ) describes an experiment investigating whether providing summer reading books to low-income children would affect school performance. Subjects in the experiment were 1,300 children randomly selected from first and second graders at low-income schools in Florida. A group of 852 of these children were selected at random from the group of 1,300 participants to be in the book group. The other 478 children were assigned to the control group. Children in the book group were invited to a book fair in the spring to choose any 12 reading books that they could then take home. Children in the control group were not given any reading books, but were given some activity and puzzle books. These children received books each year for three years until the children reached third and fourth grade. The researchers then compared reading test scores of the two groups. a. Explain why randomly selecting 852 of the 1,300 children to be in the book group is equivalent to random assignment of the children to the two experimental groups. b. Explain the purpose of including a control group in this experiment.

Short answer

a. Randomly selecting 852 out of the 1300 children to be in the book group ensures that the selection was unbiased and representative of the whole, giving credibility to the results. \n\nb. The control group in this experiment provides a baseline to compare the results of the experimental group. It helps to ascertain if the difference in test scores was truly due to the reading books or other factors.

Step-by-step solution

Explain Random Assignment

The random assignment in an experiment is critical to ensure that there are no systematic differences between or within the groups being compared, other than the experimental treatment itself. This is important because it allows the experiment to make stronger and more credible statements about causality. In other words, the differences observed in the result are due to the experiment and not some outside or extraneous factors. In this case, choosing 852 students randomly from a group of 1300 participants to be in the book group ensures that the group is a representative, unbiased sample of the broader population.

Explain Purpose of a Control Group

The control group in an experiment serves as a baseline or standard to compare with the experimental group. It helps to ascertain the effect of the experiment by providing a group that does not receive the experimental treatment. In this case, the control group of 478 children did not receive reading books but were given activity and puzzle books. The presence of the control group allows researchers to determine if getting to choose and take home 12 books each year for three years had any effect on the children’s reading test scores compared to those who didn't have such an experience.

Key concepts

Random Assignment

In the realm of educational experiments, the concept of random assignment is as pivotal as the foundation of a building. When researchers want to examine the impact of a new teaching method or resource, such as providing books to students, they must ensure that the two groups being compared are as similar as possible, except for the intervention they're testing. Random assignment is akin to shuffling a deck of cards; it ensures that each participant has an equal chance of being placed in either the experimental or control group.

Imagine you're attempting to determine if a certain fertilizer promotes plant growth. By randomly assigning plants to receive either the fertilizer or a placebo, you can confidently attribute any observed growth differences to the fertilizer, rather than other factors like soil quality or sunlight exposure. In the context of our reading experiment, random assignment assures that the book group and control group are comparable in all respects that could influence reading abilities, thereby isolating the effect of summer reading on test scores.

Control Group

The control group functions as the experimenter's yardstick. It is the group against which all changes are measured. Without this comparison group, researchers would be left questioning whether the results they see are due to the experimental treatment or caused by chance or other factors. Imagine trying to figure out if a new headache medication works without comparing it to a group that didn't receive the medication. It would be impossible to tell if people felt better because of the medication or if they would have improved on their own.

The control group in the reading experiment wasn't given the reading books but instead received activity and puzzle books. This careful approach allows the researchers to confidently say whether the provision of reading books was the key ingredient in improving reading scores or not. It helps to answer questions such as: Would children improve in reading skills over the summer without access to the chosen books, simply through maturation or other activities?

Causality in Experiments

Establishing causality is the holy grail of experimental research. In the educational landscape, it's crucial to know not just if something works, but why and how it works. Causality means that one event is the result of the occurrence of the other event; there is a cause-and-effect relationship. If we imagine a science fair, a student's elaborate volcano project isn't merely bubbling away because the fair is underway; it's erupting because of the specific chemical reaction they've initiated.

In the case at hand, the goal of providing books to students is to determine if this leads to higher reading scores – does the act of owning and reading these books cause the improvement? Random assignment and control groups are crucial in making this determination. Without these methodological cornerstones, attributing changes in reading scores specifically to the books given would be speculative at best. Researchers seek to say with certainty that it is the intervention, in this context, the access to books, that is causing the change, not other variables such as teacher quality or parental involvement.

Reading Test Scores

Reading test scores serve as a quantitative measure of a student’s literacy ability. In educational experiments, these scores help to quantify the impact of an intervention on students' reading proficiency. Much like a temperature reading indicates the severity of a fever, reading test scores signal a student’s reading health. They are a critical endpoint in literacy-based research – the metric that decides if educational programs make a quantifiable difference or not.

In our book experiment, reading test scores are the outcome being measured to determine the effectiveness of providing books to children. Higher test scores in the book group compared to the control group would suggest that the intervention was successful, much like how a scorekeeper's tallies determine the outcome of a sports game. Thus, careful consideration and transparency in how these test scores are collected, analyzed, and interpreted are vital to ensure the validity and reliability of the research findings.