International Journal on New Trends in Education and Their Implications
April 2015 Volume: 6 Issue: 2 Article: 13 ISSN 1309-6249
Copyright © International Journal on New Trends in Education and Their Implications / www.ijonte.org
157
TEACHING VARIANCE AND DEGREE
OF FREEDOM THROUGH COMPUTER-ASSISTED INSTRUCTION
Assoc. Prof. Dr. Serkan PERKMEN
Balıkesir University
Necatibey Faculty of Education
TURKEY
Yeşim SÜRMELIOĞLU
Balıkesir University
Necatibey Faculty of Education
TURKEY
ABSTRACT
The principle objective of the current study is to teach variance and degree of freedom by means of computer-
assisted instruction. Variance is regarded as one of the most important topics to learn, degree of freedom is a
concept considered as one of the most difficult concepts to teach and learn. The preliminary results on 15
faculty members showed that they had limited knowledge related to these concepts. Based on this need
analysis, we developed a video tutorial to teach these concepts using Flash and Camtasia Studio software. We
also considered visual design and instruction principles when developing the tutorial. The tutorial is made up of
three parts: population variance, degree of freedom and sample variance. The effectiveness of our tutorial was
tested on these 15 faculty members. The findings revealed substantial improvement in their knowledge about
these two concepts. They were very satisfied with the tutorial and gave us valuable insight into what can be
done to promote the instructional value of our tutorial. We strongly believe that the video tutorial we
developed has a great potential to help learners of statistics to grasp these concepts.
Key Words: Variance, degree of freedom, statistics learning, computer-assisted instruction.
INTRODUCTION
Multimedia can be defined as the presentation of knowledge as a combination of words and figures (e.g.
video). Research studies showed the positive effects of multimedia on learning (Mayer, 2007). For example,
Plasschaert, Cailleteau, Ernie (1997) found the positive effects of multimedia interactive tutorial on learning
endodontic problem-solving in the field of medicine. Lloyd and Robertson (2012) examined the role of
screencast tutorials on enhancing student learning of statistics. Screencasting can be defined as capturing what
is done on the computer screen with synched audio commentary (Udell, 2004). These researchers found that
after controlling for previous math experience, math and computer anxiety, screencast tutorials were effective
in promoting student learning of statistics.
There is empirical evidence that multimedia (specifically videos) is a beneficial tool that helps people learn
statistics. Our paper is aimed at developing a screencast video tutorial that teaches two important topics in
statistics: variance and degree of freedom. Many researchers agree that concept of degree of freedom is a
difficult concept to teach and learn (Everett , 2002). The difference between sample and variance can be
understood in the context of degree of freedom. Everett (2002) explained how difficult concept degree of
freedom is by saying “Degrees of freedom: An elusive concept that occurs throughout statistics” (p.111).
Eisenhauer (2008) gave a good real life example to explain the degree of freedom. Suppose that there are three
tasks required to be finished, which are nap, eat and read. Each task lasts 1 hour. We are required to schedule
these tasks from 1 to 4 PM. We are not completely free in doing this. If we decide to eat at 1 PM, read at 2 PM,
we are not free to choose the time of nap. It has to be at 3 PM. In this example, the degree of freedom is 3-