An educational psychologist hypothesized that presenting learning material in a

Question

An educational psychologist hypothesized that presenting learning material in a hypertext form would result in better learning than traditional text. Hypertext is electronic text containing key words that are hyperlinks, so that when they are clicked the reader moves to a portion of the text describing the key word. In this way, a reader can move about the text at will studying various topics by clicking on key words. In contrast, traditional text requires a student to read through the material in a fixed, linear fashion. The psychologist also wanted to compare hyperlinks that were structured after an expert’s knowledge of the domain with randomly structured hyperlinks.
He randomly assigned 45 astronomy students to three learning conditions: Expert Hypertext, Random Hypertext, and Normal Text, which he designated as as A1, A2, and A3, where they read and studied material on star formation. The dependent variable was scores on an exam over the studied material. Please download the Excel file attached the first question to see the results of the study. The psychologist performed an ANOVA on the data to test his hypothesis. What was the null hypothesis being tested?
What are the degrees of freedom (df) for the study?
What are the sums of squares for the different sources of variance?
What were the mean squares? The final F value?

Explanation / Answer

1.The null hypothesis(Ho) for the current study using ANOVA test can be stated as:

H0: ?1 = ?2 = ?3 ... = ?k

(where ? refers to the population mean for each of the groups)

2. Degrees of freedom(df) = n-1 ( n refers to the sample size)

In the given data: n= 45 ( the number of astronomy students)

Thus, df= 45-1

= 44

Hence, the degrees of freedom(df) is 44.

(Note: the given excel image is not very clear. It is therefore not possible to answer the last two questions. Please try to upload the image again with the remaining questions as a separate question on this portal. Hope this helps)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.