Project Math Access DVD 04 - Graphing Part 2- Part 05
Transcript Start
Audio Description: Part five; AGC, analyzing data.
KAPPERMAN: Rob, I would like to have you illustrate how you use the Accessible Graphing Calculator in analyzing data from an experiment. And we‘ll make up a fictitious experiment with fictitious clata to illustrate how a blind youngster in a science class, for example, could use the Accessible Graphing Calculator to do his or her own data analysis. And I know that you have currently in your computer, a data set of 250 points, and the values connected to those 250 points are in the negative range. So let‘s just say that our our fictitious blind student has taken the temperature of the Antarctic each clay for 250 clays and then did a data analysis of the data that emanated from that experiment. Would you illustrate how you would handle that using the calculator?
ROB: Sure, so first thing that I'm going to do is actually bring in that data set. I'm still working on that parabola we had earlier so I'm just going to go to the “file menu.“
AGC: [import data set]
ROB: “import data set“ is the top of my “file menu" so I'll hit “enter."
AGC: [file name .clat]
ROB: Right now it's looking for “.cIat" files; I can also have it look for all files. Really all I need for data is a delimited text file. So luckily this is pointing in the right clirectory.
[AGC: clirect file list, example 3-1.cIat]
ROB: So that‘s my example file we were talking about earlier. Just hit ‘‘enter‘‘ and it brings it in and automatically plots it. Sighted folks will notice that right in the expression box it says “filezexample 3-1.cIat“, that‘s my file name. My focus starts out in the data table. So if I hit “tab“, and also it plotted it so I have what looks like a scatter plot with a line through it of all that data.
AGC: [press for statistical description of data set]
ROB: So I just hit “tab“ to go to the “statistical description of data set“ button.
AGC: [text box, data set one, statistics number of points, 250]
ROB: I'm going to go ahead and stop the voice, but what that‘s doing is reading this text box of all the statistical analysis. That just kind of takes the place on the screen of the data table. Okay, I can just toggle between the two of them. So I can cursor through here. I have all the values of my regression. It tells me I'm using linear “r“ value, “a" value, “b" value, some of “x" values, mean, standard deviation, etc. And I can just cursor all the way through here.
AGC: [standard deviation 14134949227]
ROB: Okay, so if I hit “tab“ once more
AGC: [regression mode linear y equals plus px]
ROB: great, so I can tell if what regression model want. And in this drop box, there is along list, exponential logarithmic power, etc. So I can switch that. Let's look at “exponential regression."
AGC: [y equals XPX]
ROB: So I'm going to go ahead and quiet that down, but I could do several types of regressions and again this is a text box so I could copy and paste this out for my homework, so if my teacher wanted me to turn in Iet‘s say a printout of all of my data and then the statistical analysis, I would just print the scatter plot off and then I would copy and paste this data into WordPad or something and print it off and then in fact I could even braille it from there if I wanted to.
KAPPERMAN: Good, excellent. Could you illustrate or tell us how you would show the different variations of how you could display that data?
ROB: Right, so as far as plotting it, I'm going to go to the “plot page." And that is...
AGC: [calculator, plot data set one]
ROB: So here I can just tab down to “mode.“
AGC: [draw data points, check]
ROB: So right now it's doing “points“ and ‘‘line‘' and my choices are “points", ‘‘line‘' and “error bars" and I can have any of those options activated or deactivated. So for example, Iet‘s say I wanted just my points without a line through them.
AGC: [draw line through data, check]
ROB: So I just cursored over to that, un-check it. [beep] That beep tells me that my data was re-plotted and on the screen I can see just a bunch of points without a line through them.
KAPPERMAN: And that you could send to the Tiger and have it embossed so that would be accessible to a blind youngster?
ROB: Exactly, so I can feel where the clusters of my data are, you know, any outlying points and that kind of a thing. Error bars are nice, maybe not necessarily for this experiment. That shows the variability of my data or how it's changing.
KAPPERMAN: Or you can also plot that with a line through it?
ROB: Exactly, sure. So I could also have, not necessarily a best fit line, but literally a line connecting all the points, so it gives you kind of a feel for how your data is behaving physically. And then just like everything else we‘ve been plotting today, “file print" to the Tiger creates a tactile version of whatever‘s in my plot window.
KAPPERMAN: Okay, could you send one of those versions to the Tiger?
ROB: Sure.
KAPPERMAN: Could you illustrate what you're doing there?
ROB: Yeah, just like before, you just hit “control P" to go to my printer and it's already looking to the Tiger Max and it remembered all of my settings, so it's using that braille 29 font, so I'm getting computer braille labels and my title is... by default, by the way, the title is the expression. So right now it's saying “fiIe:exampIe 3-1.dat" and in “data style" because when I plotted it I wanted line and data points, it's giving me that, I could do just points or just line, either way. So anyway, it's set the way we want it, I hit “print.“
AGC: [draw line through data, clear]