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Create higher-value data
and build better models when you estimate missing data
Missing data can
seriously affect your results. If you ignore missing data or assume that
excluding missing data is sufficient, you risk getting invalid and
insignificant results. Ensure you enter the data analysis stage using data that
takes missing values into account with SPSS Missing Value AnalysisTM
as part of your data management and preparation step. SPSS Missing Value
Analysis, an SPSS add-on module, is a critical tool for anyone concerned about
the validity of data, including survey researchers, social scientists, data
miners and market researchers.
With SPSS Missing Value
Analysis, you can easily examine data from several different angles using one
of six diagnostic reports to uncover missing data patterns. You can then
estimate summary statistics and impute missing values through statistical
algorithms. SPSS Missing Value Analysis helps you to:
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Diagnose if you have a
serious missing data problem
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Replace missing values with
estimates, for example, impute your missing data with EM or Regression
algorithms
Improve the
likelihood of finding statistically significant results
Use all of your data instead of limiting your analysis to complete cases.
Easily replace missing values with estimates and increase your chance of
getting statistically significant results. Choose from the EM and regression
algorithms to predict missing values based on data you already have.
You can also draw more valid
conclusions by removing hidden bias from your data by replacing missing values
with estimates so all groups are represented in your analysis -- even those
with poor responsiveness.
Fill in the blanks when you
use SPSS Missing Value Analysis for data management
Expand SPSS® Base's
capabilities with SPSS Missing Value AnalysisTM.
Make better decisions about your data when you can fill in the blanks to create
higher-value data and build better models. SPSS Missing Value Analysis, an SPSS
add-on module, gives you procedures for data management and data prep. Also, it
easily plugs into SPSS Base ensuring you can work seamlessly in the SPSS
environment.
SPSS Missing Value Analysis
has the statistics you need to fill in missing data:
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Univariate: compute count,
mean, standard deviation and standard error of mean for all cases excluding
those containing missing values, count and percent of missing values and
extreme values for all variables
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Listwise: compute mean,
covariance matrix and correlation matrix for all quantitative variables for
cases excluding missing values
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Pairwise: compute
frequency, mean, variance, covariance matrix and correlation matrix
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EM Algorithm
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Estimate the means,
covariance matrix and correlation matrix of quantitative variables with
missing values, assuming normal distribution, t-distribution with degrees
of freedom or a mixed-normal distribution with any mixture proportion and
any standard deviation ratio
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Impute missing data and
save the completed data as a file
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Regression Algorithm
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Estimate the means,
covariance matrix and correlation matrix of variables set as dependent; set
number of predictor variables; set random elements as normal, t, residuals
or none
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Impute missing data and
save completed data as file
SPSS Missing Value Analysis
also has features that enable you to analyze patterns and manage data,
including:
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Display missing data and
extreme cases for all cases and all variables using the data patterns table
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Determine differences
between missing and non-missing groups for a related variable with the
separate t-test table
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Assess how much missing
data for one variable relates to the missing data of another variable using
the percent mismatch of patterns table
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Handle all character
variables as categorical variables
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And more
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This separate variance t-test table defines two groups of cases: those with
data on income and those that are missing data on income. Then, the
separate variance t-test table tests to see if these two groups are
different from each other on a series of variables. This table shows that
people with missing data on income are more likely to have a
non-professional occupation, more likely to be female, more likely to be
married, and have a larger family than people who reported information on
their family income.
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SPSS Missing Value AnalysisTM
system requirements


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