This Flash applet provides an introduction to simple linear regression for introductory statistics students. It combines a brief narrated animation with an interactive scatterplot function. Students are able to place points on the scatterplot by clicking with a mouse or typing X-Y coordinates. Students use these points to learn about the best fit line by placing a guess on the plot and comparing it with the least squares line. Students also learn about the value of the correlation coefficent and points that would be considered outliers. Students may also specify a value of x (within the range of the data) and obtain the resulting predicted value.
Content Quality Concerns:
The graph window is a little deceiving with respect to the minimum and maximum numbers on the graph. The boxes for the these values are extremely large and can make reading the graph somewhat difficult. This applet also uses a somewhat unusual definition of outliers by marking them at 1.9 times the standard deviation of the residuals. This is somewhat non-standard and may not match what is given in many texts.
Content Quality Strengths:
The presentation of material is well organized and provides easy access from one screen to the next. Pop-up displays provide useful assistance to students who enter incorrect information. The material has a good amount of flexibility in the amount of content students can explore. Students may choose if they want to test for significant correlation coefficient or if there are any outliers present in the data.
Ease of Use Concerns:
The last screen dealing with outliers is a bit busy and could potentially be confusing to students. The applet allows the students to move from screen to screen and back again. However, if the student forgets to put in a data point (or just wanted to add an extra one), all previous information may be lost.
Ease of Use Strengths:
The applet is well organized, and it is easy to maneuver from one screen to the next. The pop-up displays provide clear messages, and provides assistance and guidance to the student.
Potential Effectiveness Concerns:
This applet covers a very large range of material in a relatively short time period. Going from a beginning introduction of regression up through SSE and standard deviation of residuals in one sitting may be overwhelming for many students. Instructors may wish to give students a detailed assignment sheet that breaks the material up into sections and helps them track their learning. Instructors may also use this applet in class where instructors can provide details to the students.
Potential Effectiveness Strengths:
The applet coaches students through many important topics in linear regression. The applet promotes students' interaction and helps develop an understanding of linear regression.
Potential Effectiveness Rating:
Source Code Available:
Source Code Not Available
Intended User Role:
Free for All