abstract: Lots of previous studies have analyzed human tutoring at great depths and have shown expert human tutors to produce effect sizes, which is twice of that produced by an intelligent tutoring system (ITS). However, there has been no consensus on which factor makes them so effective. It is important to know this, so that same phenomena can be replicated in an ITS in order to achieve the same level of proficiency as expert human tutors. Also, to the best of my knowledge no one has looked at student reactions when they are working with a computer based tutor. The answers to both these questions are needed in order to build a highly effective computer-based tutor. My research focuses on the second question. In the first phase of my thesis, I analyzed the behavior of students when they were working with a step-based tutor Andes, using verbal-protocol analysis. The accomplishment of doing this was that I got to know of some ways in which students use a step-based tutor which can pave way for the creation of more effective computer-based tutors. I found from the first phase of the research that students often keep trying to fix errors by guessing repeatedly instead of asking for help by clicking the hint button. This phenomenon is known as hint refusal. Surprisingly, a large portion of the student's foundering was due to hint refusal. The hypothesis tested in the second phase of the research is that hint refusal can be significantly reduced and learning can be significantly increased if Andes uses more unsolicited hints and meta hints. An unsolicited hint is a hint that is given without the student asking for one. A meta-hint is like an unsolicited hint in that it is given without the student asking for it, but it just prompts the student to click on the hint button. Two versions of Andes were compared: the original version and a new version that gave more unsolicited and meta-hints. During a two-hour experiment, there were large, statistically reliable differences in several performance measures suggesting that the new policy was more effective. / Dissertation/Thesis / M.S. Computer Science 2011

In thesis themes of typography and computer font of OpenType format is described in details. At the beginning attention is paid to historical development of typeface, where stress is laid mainly on development of Roman and white letter with their characteristics. Having presented basis of typography work is concentrated on topic of digital font with emphasis on possibilities of OpenType format. Further its characteristics and advantages were listed compared to another formats and it was evaluated as format appropriate also for creating font in education process. Letterspacing and kerning were mentioned between basic graphical modifications in creating fonts. In theoretical part of the thesis they were examined in available programs designed for creating font in OpenType format. Except free available means into summary were included also commercial types due to absence of more advanced instruments and functions with free available applications. In evaluation was found that the most convenient for education is Fontlab Fontographer commercial program, free Type lite and Fontforge indicated for Open-source platform. Practical part of the thesis is focused on two chosen programs for creating main font characteristics. The goal was to detect if it is possible to reach identical results when using both programs. Fontographer program enabled to use wide tool palette dedicated to vector graphic processing by means of Adobe Illustrator similar instrument. In the case of Type lite program there were rather less instruments, what is sufficient for elementary work and familiarization with creating of digital typeface. Freeware shortage is basic absence of kerning, spacing or hinting functions. Comparing program possibilities, it falls that freeware programs based on OS Windows with their functionality are sufficient only for entry level users. The best option within free available programs is Fontforge for OS Linux which supports mentioned typographic functions. Fontographer was recommended for teaching of basic characteristics of OpenType font format. Another goal of the thesis was creating of recommended work procedure for creating basic characteristics of OpenType font for students, that is enclosed at the end of the thesis.