Data Desk is a fast,
easytouse data analysis package that has been helping people
understand their data since 1986. Data Desk provides interactive
tools for data analysis and display based on the concepts and
philosophy of Exploratory Data Analysis. Data Desk implements
many traditional statistics techniques suitable for data from
planned experiments and sample surveys. However, the program's
true strength is its powerful tools for data exploration. These
tools simplify intuitive examination of your data. No special
training in statistics is needed for these insightful graphic
displays. When you explore your data with Data Desk, you will
find patterns and relationships. But you will also bring to light
the elements that don't fit  often the most important discovery
you can make about your data.
OVERVIEW
Putting Exploratory Data Analysis to work for
you means displaying your data in many related ways. It means
computations fast enough to try out several alternative analyses
in the time that you might have expected to spend on a single
analysis. It means linking all these views of your data to get a
deeper understanding of the patterns, relationships, and
exceptions in your data.
Data Desk's interface is designed to be
simple and efficient. Modify plots and tables directly with your mouse. Add
or change variables with drag and drops. Plots and tables are stored in icons so
that they can be opened and modified later.
Data Desk provides many sources of help and
guidance. HyperView® menus, attached to every Data Desk plot and table,
provide gentle guidance and suggestions. The online Help System gives quick
access to information on the program's commands. The Quickstart Guide, Handbook
and Statistics Guide offer descriptions of commands, background statistics
information and many detailed examples. And free technical support is provided
to all registered users.
Data Desk Plus provides an even greater
level of assistance. This package combines Data Desk with ActivStats, our
statistics refresh and reference multimedia CD. ActivStats uses video,
narration, interactive tools, simulations, and web links to help you learn and
understand statistics concepts. It also shows you how to apply those concepts to
realworld data in Data Desk with special guided analysis files.
A significant amount of data is stored in spreadsheet programs like Microsoft
Excel. Data Desk ships with an Excel addin that moves data directly from
Excel into Data Desk. The data are moved without the hassle of creating and
opening an ASCII file.
Data Desk is also one of the fastest
statistics packages available on a PC or a Macintosh. For example, a
regression with three predictors and 50,000 datapoints run on a 133 MHz Pentium
PC with 16 MB of Ram computes in 1 second. A scatterplot of two of those
variables displays instantly and a 3D rotating plot of three of those 50,000
datapoint variables rotates smoothly.
Data Desk works comfortably with large files
 10,000 datapoints, 100,000 datapoints, even a million datapoints. Data Desk's
fast visual tools allow effective explorations through almost any size dataset.
Data Desk uses animation to help you see
patterns you might miss in a static display. For example, you can easily
link a sliding control to any part of an equation and see the effects of sliding
the value as displays update. Data Desk automatically makes sliders to help you
find optimal transformations of variables, to learn about the sensitivity of
analyses to small shifts in variables, and to assess the sensitivity of
nonlinear regressions. You can easily build your own animations.
The example above selects reexpressions of the
variables Assets and Sales for data on large companies. Before transformation
the variables are skewed. Moving these slider changes the reexpression of the
variables, and the displays update to show the result.
Data Desk's direct manipulation interface
provides "first person" interaction with your data rather than the "third
person" interaction found in most programs. Instead of giving the computer a
command (by typing it or filling in a dialog screen), you just pick up the
appropriate tool or icon and do the job directly. So, if you want to reposition
the points in a plot, don't tell Data Desk where to plot them verbally, pick
them up with the hand tool and move them. If you want to identify a point, click
on it. If you want to change the color or symbol of a point select it and click
on the desired color or symbol in the palettes. If you want to rotate points in
a rotating plot, push them. If you want a new variable on the xaxis of a plot,
pick up its icon and place it on the axis. This direct interface lets you act
more naturally, which simplifies and speeds analyses.
The example above shows the Query identifying a
point, the Pointer tool selecting that point, a click in the symbols palette to
change the display symbol, and the Hand tool repositioning the points to make it
easier to see the point's yaxis value.
You can modify any Data Desk plot or table
in place. Simply pick up a variable with your mouse, and drag it into the
table. The table updates instantly. To change a variable in a plot, drag a new
variable onto an axis.
Data Desk's dynamic plots and tables show
patterns and structure among several variables. Rotating plots and sliders
use animation to reveal aspects of your data that static plots cannot show.
Changing the color, symbol and selection state of datapoints instantly changes
all plots to show patterns, clusters, and outliers. Hot Set selections restrict
displays to subsets of your data with a single click.
In the example below, the scatterplot of gas
mileage by weight for a sample of automobiles is colored by the number of
Cylinders, and a line fit to each colored subset. As different countries are
selected by clicking on cells of the frequency table, the scatterplot shows only
the selected cars. It is easy to see how the cars from different countries
compare.
All Data Desk's plots and tables are linked
together so that points selected in one display highlight in all other displays.
Select bars in a bar chart or histogram, slices of a pie chart, rows, columns,
or cells of a table, or any points in a scatterplot, rotating plot, dotplot, or
boxplot, and the selected points highlight in all plots. Such consistency
reveals relationships among several variables, identify clusters and subgroups
and helps you to catch errors and outliers.
Colors and symbols are also linked across
plots. Change the color or symbol of a group of points in one plot and the
points change in all plots.
In the example above, points selected in a
scatterplot of Miles per Gallon vs. Weight are highlighted in the bar chart of
Country. Selecting the points in the high end of the weight scale shows which
country makes the heaviest cars. Selecting the US bar in the bar chart shows how
the cars built in the US compare to those built in other countries.
Any Data Desk analysis can become a template
for similar analyses of other data. Data Desk's template tools make it easy
to build a fully selfdocumented draganddrop interface for combinations of
analyses and plots. Just do the analysis once to show Data Desk what you want.
Data Desk's visual Action Control Language lets you add loops, conditional
decisions, and other basic controls with no need ever to write a program or
macro. Template files can be shared with others  even with those using Data
Desk on another operating system.
SUMMARY
Statistical Features:
 Summary Statistics: for individual variables,
broken down by categories and saved as variables: mean,
median, midrange, midquartile range, biweight, standard
deviation, variance, population standard deviation,
standard error, interquartile range, range, sum of
squares, sum, count, skewness, kurtosis, order
statistics, rank, minimum and maximum.
 Frequency Tables and Contingency Tables with
chisquare and Fisher's Exact Test, expected values,
standardized residuals, cumulative statistics and
percents.
 Standard Tests and Confidence Intervals: Including
ztests, ttests, twosample ttests, paired ttests,
pooled ttests, Ftests and a ChiSquare test of
individual variances.
 Nonparametric Tests: Sign, Paired Sign, Wilcoxon
Signed Rank and MannWhitney U. Option to include or
remove ties.
 Correlation: Pearson Correlation, Spearman Rank
Correlation, Kendall's Tau and Covariance.
 Regression: Simple Regression, Multiple
Regression, Weighted Regression, Polynomial Regression,
Stepwise Regression. Full suite of diagnostic plots and
statistics, all linked to update automatically if the
data are changed. Diagnostics include: residuals 
internally and externally studentized, leverage,
predicted values, DFFits, Cook's distance, Hadi's
Influence and Likelihood. Special diagnostic plots
include partial regression plots, potentialresidual
plots, scatterplots of predicted values vs. residual and
normal probability plots of all diagnostic statistics.
Drag new response and predictor variables into the
regression or remove them with mouse clicks; diagnostic
statistics and plots update as well.
 Nonlinear Regression: Fit virtually any function.
Interactive visual tools help you find starting values
and test the sensitivity of your results. Prebuilt
templates include: Exponential, Power, Growth, S, Log,
lnverse, Quadratic, Cubic, or customize your own
template.
 ANOVA: Special onestep command to compute Oneway
and Multiway, balanced or unbalanced, ANOVA and ANOVA
with interactions.
 General Linear Model: Nway ANOVA, ANCOVA, MANOVA,
MANCOVA and Repeated Measures; fixed effect,
randomeffect and mixed models; unbalanced designs,
nested designs, designs with missing cells and weighted
analyses. Results include a complete ANOVA table, a cell
means table and a coefficients table. Full set of
diagnostic statistics and plots. PostHoc tests,
including Scheffe, Bonferroni and Least Significant
Difference. Modify the data, factor type or model and
recompute the analysis in place. Unique OverView Table
for multivariate models. Multivariate tests for MANOVA
models include Pillai's trace, Wilk's Lambda,
HottelingLawley trace and Roy's Maximum root.
 Logistic Regression, including support for
discrete factors, interaction terms and unbalanced
designs, likelihood, coefficients and Wald statistics.
 Cluster Analysis with single or complete linkage
clustering and interactive dendogram.
 Principal Component Analysis: Saves principal axes
as equations so "nearby" versions with simple
coefficients are easy to find. The analysis computes a
summary table and variables that hold the eigenvalues,
eigenvectors and orthogonal basis vectors.
 Transformations: more than 100 functions which
include rounding, arithmetic, logical, summary,
exponential, trigonometric, string, probabilities and
many others. Select simple transformations from menus or
type in arbitrary complex functions, including
IF/THEN/FALSE. Transformed variables recompute
automatically if the data are changed, so they are always
uptodate. Prefabricated, usercontrolled, dynamic
transformations include a BoxCox transformation, Mix X
and Y, Tukey's Lambda and Dynamic Lag.
Other Features
 Unlimited number of cases and variables.
 HyperView menus offer expert, contextsensitive
suggestions.
 Action language: automate calculation and
implement new functions beyond the standard Data Desk
menus. Easytouse, objectbased programming interface.
Many standard programming commands including: Let Y:=X,
If, If else, While, Repeat, Loop, Done, Block, Abort,
Call, Initialize, Update, Case Attributes, Random,
Interface and more.
 Templates: Create prebuilt analyses for use with
other data. lncorporate drag and drop interface, push
button controls and notes for annotation and instruction.
 Efficient and flexible data management with
relational structure including random sampling,
transposing, sorting, ranking, generating patterned data,
generating random numbers, replicating, appending,
splitting variables by group, variable tables and scalar
tables.
 Consistency and Updating: Windows offer to update
if the underlying data are changed. Alternatively, view
before vs. after sidebyside.
 Data Importing: Copy' and Paste from spreadsheets,
word processors, database programs and others. Read ASCII
text files with arbitrary delimiters and Fixed Format
files.
 Combine Data Desk files; import the contents of a
saved Data Desk file into another open file. Combine
data, analyses, and derived variables.
 Exporting: Export data (as ASCII text tables),
plots (in color PICT on Mac or bitmap format on Windows)
and computed results (as tabdelimited text or picture).
 Compact datafiles dramatically reduces the size of
datafiles to make them easier to store and share with
others.
 Graphical Control: Customized graphical controls
50 you can build your own dynamic graphics.
 Full control over Font, Size and Scaling for all
plots and tables (Mac only').
 Preferences file to save defaults.
 Selector button allows subset analysis.
 Group button allows parallel category' analysis.
 HotSet variables allow subsets and categories to
be changed dynamically.
 Colors can be added to any display by group if the
variable is discrete or by rank if the variable is
continuous.
 Symbols: assign any plot symbol to the selected
points in the plot. Data plotted with that symbol will
show this symbol in all other plots.
 Slide Show Presentations let you step through sets
of windows, including text windows that provide
commentary and advice.
 Notebook Windows: Record history of analysis,
group plots and text together for printing. Plot and
tables placed into notebook are timestamped and linked
to original analyses.
 Documentation:Tutorial Quickstart Guide, Handbook
and Statistics Guide written by a statistics professor.
All contain complete discussions of the statistical
methods, examples (with data included), instructions and
a full index.
 Extremely fast computations and display.
 The application takes up about 1 MB of disk space.
Total installation is 4 MB. Requires any Mac running
system 7.0 or better with 2 MB of free RAM. Any 486 or
Pentium running Windows95 or Windows NT 4.0 or better.
 Comprehensive Help system.
 Free technical support for registered users.
Visit the Data
Desk website to view descriptions and examples of some
important Data Desk features, download a
demo or contact Red Dog Scientific
Services if you are based in Southern Africa for more
information or a demo CD.
ActivStats is a complete multimedia presentation of the
material commonly found in an Introductory Statistics course. ActivStats uses a full range of multimedia to motivate, explain,
visualize, and apply introductory statistics concepts. It
integrates video, simulation, animation, narration, text,
interactive experiments, web access, and Data Desk into a rich
learning environment.
An ActivStats for
Everyone
ActivStats Professional is designed to help you
review the statistics you have forgotten from that course you
once had (and hated) or to learn these valuable skills for the
first time on your own. It includes a specially developed
textbook written by David Moore, a world famous teacher and
textbook author. Registered ActivStats Professional owners have
the support of a web based "Teaching Assistant" free
for six months to answer your questions about statistics.
ActivStats (student version) is designed for
students to use along with an introductory statistics course or
for review or study on your own. It is designed to work with any
standard statistics text. It can be the text for a course, can
supplement any standard text (providing a builtin statistics
package at no extra cost), or can be used individually by
students wishing for study aids. The student version of
ActivStats is available for course adoption and to registered
students.
Teacher Support Materials are available to
support teachers wishing to teach with ActivStats. ActivStats can
provide vivid inclass demonstrations. Any teacher can add his or
her own materials to any page of the Lesson book.
To find out more about ActivStats
and receive a demo CD please contact Red Dog Scientific
Services.
