Data Access
Data Manipulation
SPC Capabilities
Alarms
Graphical Analysis
Statistical Analysis

Data Access

Statit e-Server takes an open approach to accessing data instead of dictating a specific data source or implementing a proprietary data storage mechanism. Statit e-Server can access data from the application or any popular database, as well as from data files or URLs.

Application Program

The Data object has methods that pass data between e-Server and the application program. This allows the Application to send data directly to e-Server for analysis and manipulation. e-Server can perform analysis and return the resulting output, or just return the transformed or summarized data back to the Application.

Databases

Statit e-Server can access any ODBC 3.0 compliant data source using SQL. All major database vendors supply ODBC compatible drivers, which must be installed on the same server where Statit e-Server is installed. End-users who access Statit e-Server do not need to have ODBC drivers installed.

Files

Data can be stored in a wide variety of file formats. Files can be read and written to the file system or to a URL location.

• ASCII Data Files
  Read and write free-format ASCII files and files in a wide variety of fixed formats.
• Binary Data Files
  Support flexible format specification to read and write binary formatted files.
• Industry Files
  Read and write data in a wide variety of popular file formats:

Data Manipulation

Statit e-Server provides a full range of data modification, manipulation, and transformation capabilities, including conditional transformations, subsets, sorting and ranking.

Many built-in functions for arithmetic, mathematic, statistical, and trigonometric transformations are provided. String, date, and time manipulation functions are also available. Statit e-Server can:

• Modify and compute new data items and variables
• Perform conditional computations based on logical criteria, using the entire data set or only a subset of data
• Change values, combine categories or collapse intervals
• Rank variable observations as well as lag or lead over time periods
• Calculate moving averages and ranges
• Format data for display
• Convert data variables to other data types

SPC Capabilities

Most of the variable and attribute control charts offer these features:

• Data Tips (HTML output only)
  When the user clicks on a subgroup point a pop-up window displays information about the subgroup, such as the underlying data, plotted value and X-axis identification. Other information that can be displayed includes: subgroup average, min, max, range, control limits and specification limits. Data from related variables can also be included, for example Shift, Operator and Machine information.
• Assignable Causes
  Points on the chart can be excluded from control and warning limit calculations and rules testing. This feature is often used to identify out-of-control points for which an assignable cause has been found. The identifying text string is displayed on the chart near the point.
• Stratification and Phases
  Used to displays effects of process changes. This feature is used in conjunction with a categorical variable. When the value of the categorical variable changes, then the new value is displayed above the data space in a block-style legend. Control and warning limits can be calculated separately within each category defined by a categorical variable.
• Variable Samples Sizes
  Subgroups can be identified either by the constant subgroup size or by a categorical variable, such as date and time or lot number.
• Missing Data Handling
  Missing data for a subgroup is identified and omitted from calculations where appropriate.
• Short-Run
  Short-Run and small production lot capabilities are supported.
• Annotation
  Labels for special events that influence subgroups are supported. Text can be placed near any point on the chart.
• Limits
  There is a great deal of flexibility for displaying Control, Warning and Spec limits, including how they are computed, displayed and labeled.
• Data Table
  An optional display of detailed information can be included below the chart. The choices include the underlying data, subgroup values and control limits. Other details and variables can also be specified.
• Text Reports
  A text report can be generated which lists the control limits, rules tested and violated and outliers.

Alarms

Statit e-Server provides flexible options for defining and responding to SPC Rule violations.

SPC Rules Testing

Western Electric, AT&T, Nelson and Ford rules are supported. Existing rule sets can also be modified and new rule sets can be created.

Statit e-Server provides the application with significant flexibility in determining the characteristics of Alarm conditions. Applications can detect and process various alarm conditions including:

• Last point out of control
• Any point out of control
• Specific rules violated
• Rules violated in last n samples

Visual Notification

Some of the ways that e-Server can inform a user that a rule violation has occurred include:

• Identify specific SPC rule violations by placing an identifier next to the data point. Statit e-Server does this automatically by displaying a letter which indicates the rule violated. If the user clicks on the letter, a description of the rule is displayed as a Data Tip.
• Change the colors of the graph.
• Add a text message to the graph.
• Include customized HTML effects like banners, blinking text and animated gifs.

Graphical Analysis

Statit e-Server offers built-in charts for performing graphics analysis and provides complete capabilities to customize the appearance of all graphics output. Graphical analysis tools include:

• Quality Tools - Pareto, histogram, scatterplot, runs chart, fishbone
• Relationship Plots - XY plots, scatterplot matrix, regression
• Frequency Charts - pie, bar
• Distribution Plots - box, probability, percentile, Q-Q

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Statistical Analysis

Statit e-Server supports a wide variety of statistical capabilities including:

• Descriptive statistics, including univariate, multi-way univariate, frequency distributions and frequency tables
• One and two-sample inference
• Analysis of variance
• Correlation analysis
• Regression analysis
• Multivariate analysis
• Reliability and survival analysis

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