Object Reference : Graph Creation Commands
  
 
qqplot
Display a quantile-quantile graph.
Plots the (empirical) quantiles of a series or matrix column against either the quantiles of a theoretical distribution or the empirical quantiles of other series or columns in the group or matrix. You may specify the theoretical distribution and/or the method used to compute the empirical quantiles as options.
Syntax
qqplot(options) o1 [o2 o3 ... ]
object_name.qqplot(options) analytical_spec(arg) [categorical_spec(arg)]
where o1, o2, ..., are series or group objects.
When used as a command, qqplot displays the theoretical qq-plot against a fitted normal distribution.
When used to display the view of an object, you must specify a theoretical or empirical quantile graph in the analytical_spec (see “Analytical Spec”).
The optional categorical_spec allows you to specify a categorical graph (see “Categorical Spec”).
Options
Multiple series pair options (categorical graph settings will override these options)
 
s
Plot in a single graph (applies only to theoretical QQ and symmetry Q-Q graphs).
mult= mat_type
Multiple series or column handling: where mat_type may be: “pairs” or “p” - pairs, “mat” or “m” - scatterplot matrix, “lower” or “l” - lower triangular matrix.
Template and printing options
 
o=template
Use appearance options from the specified template. template may be a predefined template keyword (“default” - current global defaults, “classic”, “modern”, “reverse”, “midnight”, “spartan”, “monochrome”) or a graph in the workfile.
t=graph_name
Use appearance options and copy text and shading from the specified graph.
b / -b
[Apply / Remove] bold modifiers of the base template style specified using the “o=” option above.
w / -w
[Apply / Remove] wide modifiers of the base template style specified using the “o=” option above.
reset
Resets all graph options to the global defaults. May be used to remove existing customization of the graph.
p
Print the graph.
The options which support the “–” may be preceded by a “+” or “–” indicating whether to turn on or off the option. The “+” is optional.
Panel options
The following option applies when graphing panel structured data.
 
panel=arg (default taken from global settings)
Panel data display: “stack” (stack the cross-sections), “individual” or “i” (separate graph for each cross-section).
(Note: more general versions of these panel graphs may be constructed as categorical graphs.)
Analytical Spec
Specify the type of quantile-quantile graph you wish to create in the analytical spec. For a description of quantile-quantile graphs, see “Analytical Graph Types”. The analytical spec should be in the form:
qq_type(type_options)
where qq_type may be one of the following keywords:
 
theory
Theoretical quantile-quantile plot.
empirical
Empirical quantile-quantile plot (requires at least two series or columns of a matrix)
symmetry
Quantile quantile symmetry plot.
You may provide multiple theoretical qq-plot elements, but may not have more than one empirical qq-plot, nor may you mix the two.
Each type has its own set of options, to be entered in type_options:
Theoretical Options
 
dist=arg
arg can be: “normal”, “exp” - exponential, “logit” - logistic, “uniform” - uniform, “xman” - extreme max, “xmin” - extreme min, “chisq” - chi-squared, “pareto” - Pareto, “weibull” - Weibull, “gamma” - gamma, “tdist” - Student’s t-distribution.
p1=int
Set first parameter.
p2=int
Set second parameter.
p3=int
Set third parameter.
q = arg
Set the quantile method, where arg can be: “r” - Rankit-Cleveland, “o” - Ordinary, “v” - van der Waerden, “b” - Blom, “t” - Tukey, “g” - Gumbel.
noline
Don’t display a fit line.
m=int
Set the iterations maximum. (Applies to logistic, extreme max, extreme min, chi-squared, Weibull, gamma, or t-distributions.)
c =int
Sets the convergence criterion. (Applies to logistic, extreme max, extreme min, chi-squared, Weibull, gamma, or t-distributions.)
s
Use user-specified starting values, supplied in the C coefficient vector in the workfile (default uses EViews supplied starting values). (Applies to logistic, extreme max, extreme min, chi-squared, Weibull, gamma, or t-distributions.)
leg=arg
Specify the legend display settings, where arg can be: “def” - default, “n” - none, “s” - short, “det”- detailed.
Empirical Options
 
q=arg
Set the quantile method, where arg can be: “r” - Rankit-Cleveland, “o” - Ordinary, “v” - van der Waerden, “b” - Blom, “t” - Tukey, “g” - Gumbel.
noline
Don’t display a regression line.
leg=arg
Specify the legend display settings, where arg can be: “def” - default, “n” - none, “s” - short, “det”- detailed.
Examples
Theoretical examples
qqplot(s) inf unemp
displays theoretical qq-plots for INF and UNEMP against fitted normal distributions in a single frame.
group g1 inf unemp
g1.qqplot theory
displays theoretical qqplots of INF and UNEMP compared with normal distributions fitted to the data in each series. The graphs include fit lines and are displayed in separate frames.
g1.qqplot(s) theory(dist=exp)
compares INF and UNEMP with fitted exponential distributions, and displays the graphs in a single frame.
g1.qqplot(s) theory(dist=exp, p1=5)
plots the series against the quantiles of an exponential distribution with parameter 5 in a single frame.
Empirical Examples
group g2 ser1 ser2 ser3 ser4
g2.qqplot empirical
displays empirical qqplots for pairs of series in G2. The default behavior is to plot the first series in the group (SER1) against the remaining series (SER2, SER3, and SER4). The graphs include fit lines and are displayed in separate graph frames.
g1.qqplot(mult=pair) empirical(noline)
displays qqplots of SER1 versus SER2 and SER3 versus SER4 in separate graph frames, without a regression line.
Categorical examples
g1.qqplot theory within(age)
displays theoretical qq-plots with the series in G1 treated as the within factor and @SERIES treated as the across factor. The qq-plots for each series in G1 will be displayed in separate frames, with multiple qq-plots for each AGE category shown in each frame.
g1.qqplot(mult=p) empirical across(age)
displays empirical qq-plots for categories of AGE in separate graph frames.
Cross-references
For a description of quantile-quantile graphs, see “Analytical Graph Types”.
See “Graphing Data” for a detailed discussion of graphs in EViews, and “Templates” for a discussion of graph templates. See Graph::graphfor graph declaration and other graph types.