Graphical Analysis Ill David L. Vernier. Vernler Software. 2920 SW 89th St., Portland, OR 97235 Hardware: Apple II family Components: 1 disk and 50-page manual Level and Subject: High school sciende; technique of graphing Cost: $24.95
Graphical Analysis III is a complete graphing cool suitable for high school as well as collegenppliratk,ns. It hasa wide range iS optionivarying in complexity from the simple plotting of a two-dimensional linear graph with appropriately labeled axes to a more complex statistical treatment of data. The program will extrapolate, interpolate, integrate, and find linear regressions, as well as handle logarithmic and exponential functions. It allows up to 4 plots per graph, with 512 possible data sets. The data are easily converted to a bar graph format if desired. A rounding option allows the user to choose between rounding by a specific number of significant figures or by the number of digits to the right of the decimal point. Thegraphs are drawn in high-resolution graphics with options such as a background grid, point protectors, and error bars. The graphs can be saved t o disk or he easily printed on paper with an Imagewriter printer or with a Grappler+ or PKASON interface card. A most annealine feature of G r a ~ h i c Analvsis s 111 is itsabilit; to transfer data to and from Appleworks files. By taking advantage of the sample data files included on the disk, the teacher can use it as a demonstration twl. The construction and use of graphs, as well as the relationships between variables can easily be
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the~" rieht t o make unlimited conies for school ~ U Wand , the right to use the propam on hard disk network systems. This price also includes the 50.psge instruction manual which not only documents the program, hut also includes a section on suggested classroom uses and a complete section on the program design. The manual is well indexed and easy to use. The program was used by my Chemistry I1 class to plot data from a heat of neutralization lab. The students had little or no difficulty in plotting the data and printing out the graph with an MX-80 printer and Grappler+ card. However, some had used a temperature probe interface program for the actual collection of data. For these students, whose graph had already been plotted and printed out via computer, there were some misgivings about having t o input the data. Since interface probes are becoming quite common, i t would be most beneficial if Graphical Analysis 111could be modified to allow for data input directly from such devices. Data files from other sources can he used with the program, but they must first be converted to ProDOS, which is timeconsuming and tedious. A few additional suezestions for imnrove,... mpnt were given hy the students. It should be noted that they were wing the program without access to the manual or the refrr-
taught by displaying the program on a larp;? monmr. Class data can be compiled and analyzed q u ~ k l y Various . sets of students' data can he compared and the results explained t o the whole class. For advanced students, the program can he used an an individual basis to save time and to generate attractive graphs for their laboratory notebooks or Science Fair projects. Using Graphical Analysis 111 for teaching relationships between variables is advantageous. In the MODIFY DATA option, one can easily modify either variable in the following ways: raise t o a power, log to base e, log to base 10, sine, cosine, tangent, add a constant or multiply by a constant. These various modifications can be made and then the graph quickly plotted tosee if astraight line results. I anticipate using this feature with my Chemistry I1 students to explain the graphical relationships that are an integral part of reaction kinetics and rate laws. The program is completely user friendly, requiring little orno reference to the manual except for more detail. A Quick Reference card is supplied with the program that lists and briefly explains the various command functions. The program is menu driven and the progression is very logical and simple. There are no hang-ups in the program, even when accessing the printer or saving to disk. Error trapping is most efficient. The entire program is written in BASIC and can easily be accessed and modified. For the modest price of $24.95, the purchasing school has
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Summary Ratings: Revleuer Cateary Ease of Us: Subjen Mansr Content: Pedagagic Value:
Student Reaction:
Re~Iewer II
I
Excallent Excellent G o d to Excellent Good
Excellem
Excellent Very Good Mod
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,,, , ,,." Computer Learning Packages t".,"..""
Reviewer DavidL. Vernier. Graphical Analysis, Ill
Jeanette Carpenter
Donald L. Pavia, Lewis Diagrams
Caroline H. Bowers William P. J e n s e n Donald A. Tarr
Bmks Malcolm M. Renfrew George B. Kauffman
Jay A. Young, editor, Improving t h e Chemical Laboratory Arnold Thackray, compiler, Contemporary Classics in Physical, Chemical, and Earth S c i e n c e s Sally Solomon, Introduction t o General, Organic, and Biological Chemistry New Volumes in Continuing Series Textbooks Titles of Interest Monographs
Roger DeKock
Volume 65
Number 10
October 1988
A269
ence card. Several requested a HELP menu. Other requests included: a n on-screen prompt on the graph page that ESC returns one t o the previous menu; errors in data entry should be easier t o correct; when redrawing graphs, graph styles should not have to be reseleeted; in File Options, the catalog should not scroll, unless an onscreen prompt he given on how to stop it. In general the students were impressed with the program. They especially liked the convenience of plotting different data sets on the same graph, and the easy-to-use and efficient statistical analysis. Vernier's Graphical Analysis I11 is a versatile and practical program. Its ease of use is probably the most outstanding feature. The reward of seeing one's data plotted n e a t h in such s fast and efficient manner. plus theadded honwuf beingabl~tuusethe program as a teaching tool for introducing and perfecting basic graphing rkillr are reasons enough to make this small investment. Graphical Analysis I11 provides a tool that no high school with access to Apple computers should he without. Jeanette Carpenter MacAnhur High School 2923 Bihers Road San Antonio. TX 78217 ~
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This program provides high school or early college teachers and students with an easy to use tool for the graphing and the analysis of data. All students should, of course, he able to plot a graph by hand. Once that skill has been demonstrated, however, repeated manual plotting is a tedious waste of time. Alternatively, the computer quickly executes the repetitive platting tasks and allows the student to concentrate on the discovery of relationships between variables. Graphical Analysis I11 is sufficiently sophisticated to transform data before graphing by using simple arithmetic, transcendental functions, or exponents designated by the user. Yet the program remains sufficiently simple and streamlined to enable high school students to use the program effectively after only a few minutes of instruction. In fact, each of my advanced placement chemistry students, all of whom are a t least somewhat computer literate, used the program t o generate printed copies of graphs of their own experimental data (ahsorbance measured using a spectrophotometer versus concentration) after only two or three minutes of instruction. Because little will have heen gained if a simple, tedious task of manual plotting is exchanged for a complex, difficult task of using a computer program, one of the most important criteria for judging the effectiveness of such an applications program is ease of use. Both my AP students and other students in a second-year chemistry course a t our school expressed delight a t the release from drudgery of graphing many data points manually. The nested menu-driven format in this program, whieh is very similar t o the one employed in Appleworks(TM), is simple and straightforward t o use. Each menu comes t o the screen with the most
A270
Journal of Chemical Education
common or most likely option selected as a default and highlighted in reverse video. Movement through the menu is easily accomplished using arrow keys or, usually, single letter designations. Pressing the escape key aborts any operation in progress and returns the user t o the previous menuan important feature to reduce potential student frustration. Graphical Analysis I11 generates graphs from data which have been entered from the keyboard or have been saved previously t o disk. The program accommodates up t o 512 pairs of data which can be expressed in standard or exponential notation. Data are designated as "horizontal axis values" or "vertical axis values." The user enters hoth lahels and units for each axis. Unfortunately, the graph title is predetermined and limited to a combination of axis labels. The data in mrmory may easil) he amended hy \urting in numrrical order arcording to horiwntal axis vnlue, by editing individual pairs, groups of pairs, axis lahels, or axis units, by exchanging the axes, by adding pairs, or by deleting pairs. In short, no entry is immutable. The data entered from the keyboard can be saved to disk using a file name designated bv the user. Subseouentlv. ,. all files can be accessed from disk, and prwiiion is made so that it is not nwesrary tu leave the prugram to obtain a catalog of file names. An ddditional feature that greatly increases the scope of the program is that any data table can be transferred to an Appleworks(TM) spreadsheet or data base and ultimately passed to the word processor for inclusion in a reoort. ~ e f o rthe e graph ran be printed on paper. it must firat he dirplayed in high resolution paphira on the screen. A numher of options are available to allow the user maximum control over the appearance of the display. The student may select sealing factors for each axis or the program may generate scales appropriate to the data. If the program is being used by students who are just learning to graph data ijunior high students would be capable of using this program) a comparison between their graphs and those generated with computer-selected scales should he a valuable learning experience. Students may select options t o he added to the two-labeled-axes-and-points graph, which is the minimum. For example, the points may be surrounded by small geometric figures. Since the program allows up to four sets of data to be plotted on the same pair of axes, different figures serve to separate the points for each different series. This feature would be useful if a teacher wanted t o compare graphs of similar data from different lab groups in the class. Additional choices include a line connecting points andlor a regression line. A bar graph is also an option; the user selects the width of the bars. For any type of graph, the user may elect to include a background grid of points so that the final result resembles graphs drawn on graph paper. Teachers who place emphasis on the uncertainty of measured values will find that the program accommodates a number of methods to reflect the uncertainty of the data. First, the number of significant digits to which data should be rounded is preset a t three. This number can be adjusted with a "Change Rounding" command which allows the designetion of either the number of significant digits or the number of places after
the decimal t o whieh each datum is displayed. Unfortunately, the number of significant digits set is applied t o both horizontal and vertical axes values. In other words, there is no way to set "3" as the numher of significant figures for data of one axis while setting "4"for the other axis. Graphs themselves may include a display of uncertainty if, in preparing for graphing, the style option ' "Error Bars" is selected. This selection causes the uncertainty in hoth vertical and horizontalaxesvalues to he displayed on the graph. The user enters either the absolute error or the percent error for the data for each axis. Although students might find use for the program in plotting nonlinear graphs such as titration curves or cooling curves which include phase changes, the strength of Graphical Analysis I11 lies in the production of linear graphs and the numerical analysis of such data. For example, the user may choose to have printed directly on the graph rheslopeand intercept of the regression l ~ n e and the rorrelation roefficient derrrihing thr relations hi^ of data D a m If the "Extrapolate or 1nterpo1ate"bption is selected and any horizontal axis value is entered, the corresponding vertical axis value of the point an the regression line will be returned. Therefore, the ease with which data may be transformed into pairs which can be tested for a linear relationship is critical if the program is t o achieve its purpose. In preparation far graphing to test for a linear fit, the data ore easily transformed by the selection of an appropriate operation from a menu. The data of each axis can he transformed indrpendently with the following choices: raisr to a power, log to the base P. 101: to the base 10, sine, cosine, tangent, plus a constant, and times a constant. Data so transformed can he displayed on the screen, printed on paper, and graphed using all of the options available for the original data. The data transformed once can he modified main. ~ -hut then ~ the ~ first. modification is lost. Fur examplr,thr usrrcannot add nconstnnt to all verticnl axis valnes and then take the logarithm of the resulting sum. However, the program does have the capability of transferring data t o an Appleworks(TM) spreadsheet where appropriate manipulations will modify the data. These new data can now be returned to Graphical Analysis I11 for further transformation and graphing. The approximately 50 pages of clearly written documentation is divided into two major sections, a User's Manual and a Teacher's Guide. However, the distinction between the two parts based on these lahels is not meaningful. Far example, in addition to giving the teacher advice and suggestions regarding t h e use of t h e program, t h e Teacher's Guide also containsspeeifie directions for transferring files between Graphical Analysis 111 and Appleworks, directions for converting files t o ProDOS which is used for Graphical Analysis 111, hardware requirements for the printing graphs and other topin which should mvre appropriately have hem "laced in the User's hlanual. Sev. era1 verv nice features of the documentation are aimed at reducing thr timp n new user mast spend readingdocumentation m a pre. vious uaer must spend weking a review of commands. Included on card stock is a single summary sheet that includes all commands, operations, modes, and definitions of symbols. A seven-page section of the ~
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User's Guide gives students sufficient information "to enter data and plot a few graphs without confusing them with all of the other features of the program." Although neither the documentation nor the format of the program implies that this package is a tutorial on graphing or data analysis, two of the seven pages in this introductory section do describe the process used t o find the relationships between variables using this program. The documentation contains no index, but the table of contents sufficiently describes the location of all topics. Teachers of introductory chemistry courses in high school or college might use this program t o have students find linear relationships when they apply a discovery approach to the topic of ideal gas laws or when they illustrate graphical methods of determining the order of a reaction for kinetics experiments. Physics teachers may find more applications than chemistry teachers. In f a d , most of the sample data files included with the program are drawn from physics experiments. In addition, teachers who wish to illustrate the graph of a certain function can do so by either modifying data files prepared by the author or by creating their own data files with DATAMAKER, a BASIC program also present on the disk. Instructions for both methods are included in the Teacher's Guide section of the documentation. Graphical Analysis I11 is written in BASIC. Clearly the author welcomes any user who wishes to make desired changes in the program. The back of the disk contains a fully remarked version of the programs. The documentation contains "Program Design Notes," a table listing the symbols for variables, a memory map, and instructions simple enoughto enablethe mast inexperienced of programmers t o make avariety of modifications. For example, some teachers may object t o the occasional use of sounds as signals; such sounds may be removed from the program. However, by using easily modified BASIC code the author has not sacrificed execution speed. Typical data analysis and graphing on the screen requires 10-20 seconds. When a delay occurs, the screen displays a message describing the activity. Printing times depend on the printer used. In addition to supporting conventional Apple1Imagewriter configurations, the program supports dot matrix printers interfaced with the Grappler+(TM) or t h e PKASORI(TM) card. The program's author, former physics teacher David Vernier, clearly understands the level of complexity and program transparency required for an applications program of this nature to be useful to high school and early college level students and faculty. Furthermore, Vernier Software continues support of its software purchasers by distributing a newsletter t o science teachers in which updates of programs are offered usually a t no cost. When a major revision does occur, owners of the old version are offered the new program a t a greatly reduced price. For example, purchasers of Graphics Analysis I1 may obtain Graphical Analysis I11 by returning the original disk and remitting a nominal $10 charge. The program is not copy protected. A letter from the author that accompanies the software states that the purchaser may make as many copies of the program "as you wish for use within your school a t no extra
cost." This very fair policy and the reasonable cost of this well-designed and versatile applications program should make it one that any science faculty would be anxious t o purchase and use with students. Caroline H. Bowers Spring Valley High School Sparkleberry Lane Columbia. SC 29223
DonaldL Pavra, COMPress. P.0 Box 102. Wentworth. NH 03282 Hardware: IBM PC (or compatible) with color graphics adapter Components: 1 disk and User's Manual Level and Subject: General Chemistry Cost: 540
This software is designed t o help students determine Lewis structures of molecules and ions. All 48 molecules and ions included in the program obey the octet rule; that is, all nonhydrogen atoms have eight electrons in theexpected answer. In addition todeterminine the correct Lewis structure. students are h&ed to understand the forn,al charge a~signmentof each alum :n a pnrtirular structure. They are expected to find the currect arrangement of atoms within the structure as well as the most logicalcharge distribution. In cases where more than one answer fits the rules the student is t o deduce the best Lewisstructure. Help is provided, if requested, every step along the way to a correct solution. The program is intended for college general chemistry students and students in a first-year organic chemistry course. This software could he used as an introduction to Lewis structure concepts, since no background in Lewis structure determination is assumed. A modest background in drawing Lewis structures and in the use of an IBM compatible computer would he helpful. A background in atomic structure, covalent bonding, and electronegativity concepts is assumed. The documentation clearly explains the features provided in the program and indicates the types of commands that are used. In addition, help is included a t each step in the procedure and a student can go to any level auicklv with s i m ~ l kevstrokes. e , Installation proredurea needed L O run the program for the first timenresimply expinin~d. However,thispn~cedurcdidnot workdue to ~
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Volume 65
failure of my system t o recognize the B drive. I was not able to install DOS on the disk provided and was forced to begin the program each time using commands not included in the directions. Once the installation procedure is complete there is, according to the directions, no way to change the parameters. Required tables such as a periodic table, valence electron tahle, etc. are readily accessible from any point in the program, although a novice computer user would do well to have these tables available in hard copy. After the program is initially loaded disk I10 operations are performed quickly, and students are not required to wait for extended oeriods of time while internal tasks are completed. The program behaves as claimed in the documentation and no surprises were encountered in the execution of the software. Needed calculations may be done without aid of any kind and results can be printed out a t the end of a session with a minimum of difficulty. Students have a number of rules and manipulations to master and probably need to use the program several times to gain the maximum benefit. The first time through students will understand the rules and operations of the program. During all succeeding times students will learn to apply this information t o produce Lewis structures. Prompts are unambiguous and helpful and one may easily recover from almost any situation with a minimum knowledee of eompurer operations. When nn answer is tl, he submittrdforanalysirtheroftunreisat~letu handle errors in an mformat~veand helpful fashion. T h e programmer has cleverly adapted the program to recognize correct as well as different types of incorrect answers even when a variety of answer formats is possible. Atoms, bonds, and lone pairs may he placed in any orientation as long as the answer is correct. Many incorrect answers produce clues that help identify the problem, and the HELP command allows students to work their way out of a problem. If the students have no idea how to correct a problem, the answer is iust a keystroke away. The program may be used by individuals, small groups, or by an instructor in a large classroom setting. The atoms, bands, and electron pairs are displayed in characters sufficiently lmge to be displayed using a LCD screen overhead projector. Instructors may choose to generate any of the 48 structures available. Bonds and especially electron pairs that often are not seen on the chalkboard from the back of a large room are clearly visible in this display. (Continued on page A272) ~
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October 1986
A271
