Forecasting
The BX Tab
November 19, 2016
MetrixND provides several options for determining whether a variable is useful. Typically, a model builder reviews the variable coefficients, standard error, t-statistic and p-values. These statistics are located on the “Coef” tab as shown below.
An evaluation of the variable coefficients shows that each variable is significant and behaves as expected. For instance, the CDD70 variable has a t-statistic of 11.563 (statistically significant) and indicates that when cooling degree days (CDD70) increase, sales increase by 1.896 units.
While these numerical results are useful, a graphical depiction of the variable aids the understanding of the variable’s contribution to the model. In the regression model object, the BX tab provides the picture of each explanatory variable’s contribution to the predicted value.
In the figure below, the contribution of CDD70 (red line) is compared to the model’s predicted value (blue line). Formally, the CDD70 line is calculated from the CDD70 variable value and the CDD70 coefficient (BCDD70 x XCDD70).
The power of the graphic is visual clue about what each variable is doing to generate the predicted value. In this example, the CDD70 variable is responsible for the summer cooling shape.
A closer inspection of the graphic (zooming into 2014 in the figure below), shows how CDD70 only contributes to the predicated values in May through October. So while the predicted value decreases from April to May, the graphic tells us the decrease is not caused by the CDD70 variable because CDD70 does not contribute to the April predicted value.
Coupled with the traditional variable statistics, the BX view enhances the model builder’s understanding of variable’s contribution and power. Begin using the BX tab and add it to your box of model building tools.
An evaluation of the variable coefficients shows that each variable is significant and behaves as expected. For instance, the CDD70 variable has a t-statistic of 11.563 (statistically significant) and indicates that when cooling degree days (CDD70) increase, sales increase by 1.896 units.
While these numerical results are useful, a graphical depiction of the variable aids the understanding of the variable’s contribution to the model. In the regression model object, the BX tab provides the picture of each explanatory variable’s contribution to the predicted value.
In the figure below, the contribution of CDD70 (red line) is compared to the model’s predicted value (blue line). Formally, the CDD70 line is calculated from the CDD70 variable value and the CDD70 coefficient (BCDD70 x XCDD70).
The power of the graphic is visual clue about what each variable is doing to generate the predicted value. In this example, the CDD70 variable is responsible for the summer cooling shape.
A closer inspection of the graphic (zooming into 2014 in the figure below), shows how CDD70 only contributes to the predicated values in May through October. So while the predicted value decreases from April to May, the graphic tells us the decrease is not caused by the CDD70 variable because CDD70 does not contribute to the April predicted value.
Coupled with the traditional variable statistics, the BX view enhances the model builder’s understanding of variable’s contribution and power. Begin using the BX tab and add it to your box of model building tools.
Si è verificato un errore nell'elaborarazione del modello.
The following has evaluated to null or missing:
==> authorContent.contentFields [in template "44616#44647#114455" at line 9, column 17]
----
Tip: It's the step after the last dot that caused this error, not those before it.
----
Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing</#if>. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??
----
----
FTL stack trace ("~" means nesting-related):
- Failed at: contentFields = authorContent.content... [in template "44616#44647#114455" at line 9, column 1]
----
1<#assign
2 webContentData = jsonFactoryUtil.createJSONObject(author.getData())
3 classPK = webContentData.classPK
4/>
5
6<#assign
7authorContent = restClient.get("/headless-delivery/v1.0/structured-contents/" + classPK + "?fields=contentFields%2CfriendlyUrlPath%2CtaxonomyCategoryBriefs")
8contentFields = authorContent.contentFields
9categories=authorContent.taxonomyCategoryBriefs
10authorContentData = jsonFactoryUtil.createJSONObject(authorContent)
11friendlyURL = authorContentData.friendlyUrlPath
12authorCategoryId = "0"
13/>
14
15<#list contentFields as contentField >
16 <#assign
17 contentFieldData = jsonFactoryUtil.createJSONObject(contentField)
18 name = contentField.name
19 />
20 <#if name == 'authorImage'>
21 <#if (contentField.contentFieldValue.image)??>
22 <#assign authorImageURL = contentField.contentFieldValue.image.contentUrl />
23 </#if>
24 </#if>
25 <#if name == 'authorName'>
26 <#assign authorName = contentField.contentFieldValue.data />
27 <#list categories as category >
28 <#if authorName == category.taxonomyCategoryName>
29 <#assign authorCategoryId = category.taxonomyCategoryId />
30 </#if>
31 </#list>
32 </#if>
33 <#if name == 'authorDescription'>
34 <#assign authorDescription = contentField.contentFieldValue.data />
35
36 </#if>
37
38 <#if name == 'authorJobTitle'>
39 <#assign authorJobTitle = contentField.contentFieldValue.data />
40
41 </#if>
42
43</#list>
44
45<div class="blog-author-info">
46 <#if authorImageURL??>
47 <img class="blog-author-img" id="author-image" src="${authorImageURL}" alt="" />
48 </#if>
49 <#if authorName??>
50 <#if authorName != "">
51 <p class="blog-author-name">By <a id="author-detail-page" href="/w/${friendlyURL}?filter_category_552298=${authorCategoryId}"><span id="author-full-name">${authorName}</span></a></p>
52 <hr />
53 </#if>
54 </#if>
55 <#if authorJobTitle??>
56 <#if authorJobTitle != "">
57 <p class="blog-author-title" id="author-job-title" >${authorJobTitle}</p>
58 <hr />
59 </#if>
60 </#if>
61 <#if authorDescription??>
62 <#if authorDescription != "" && authorDescription != "null" >
63 <p class="blog-author-desc" id="author-job-desc">${authorDescription}</p>
64 <hr />
65 </#if>
66 </#if>
67</div>
The following has evaluated to null or missing:
==> authorContent.contentFields [in template "44616#44647#114455" at line 9, column 17]
----
Tip: It's the step after the last dot that caused this error, not those before it.
----
Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing</#if>. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??
----
----
FTL stack trace ("~" means nesting-related):
- Failed at: contentFields = authorContent.content... [in template "44616#44647#114455" at line 9, column 1]
----
1<#assign
2 webContentData = jsonFactoryUtil.createJSONObject(author.getData())
3 classPK = webContentData.classPK
4/>
5
6<#assign
7authorContent = restClient.get("/headless-delivery/v1.0/structured-contents/" + classPK + "?fields=contentFields%2CfriendlyUrlPath%2CtaxonomyCategoryBriefs")
8contentFields = authorContent.contentFields
9categories=authorContent.taxonomyCategoryBriefs
10authorContentData = jsonFactoryUtil.createJSONObject(authorContent)
11friendlyURL = authorContentData.friendlyUrlPath
12authorCategoryId = "0"
13/>
14
15<#list contentFields as contentField >
16 <#assign
17 contentFieldData = jsonFactoryUtil.createJSONObject(contentField)
18 name = contentField.name
19 />
20 <#if name == 'authorImage'>
21 <#if (contentField.contentFieldValue.image)??>
22 <#assign authorImageURL = contentField.contentFieldValue.image.contentUrl />
23 </#if>
24 </#if>
25 <#if name == 'authorName'>
26 <#assign authorName = contentField.contentFieldValue.data />
27 <#list categories as category >
28 <#if authorName == category.taxonomyCategoryName>
29 <#assign authorCategoryId = category.taxonomyCategoryId />
30 </#if>
31 </#list>
32 </#if>
33 <#if name == 'authorDescription'>
34 <#assign authorDescription = contentField.contentFieldValue.data />
35
36 </#if>
37
38 <#if name == 'authorJobTitle'>
39 <#assign authorJobTitle = contentField.contentFieldValue.data />
40
41 </#if>
42
43</#list>
44
45<div class="blog-author-info">
46 <#if authorImageURL??>
47 <img class="blog-author-img" id="author-image" src="${authorImageURL}" alt="" />
48 </#if>
49 <#if authorName??>
50 <#if authorName != "">
51 <p class="blog-author-name">By <a id="author-detail-page" href="/w/${friendlyURL}?filter_category_552298=${authorCategoryId}"><span id="author-full-name">${authorName}</span></a></p>
52 <hr />
53 </#if>
54 </#if>
55 <#if authorJobTitle??>
56 <#if authorJobTitle != "">
57 <p class="blog-author-title" id="author-job-title" >${authorJobTitle}</p>
58 <hr />
59 </#if>
60 </#if>
61 <#if authorDescription??>
62 <#if authorDescription != "" && authorDescription != "null" >
63 <p class="blog-author-desc" id="author-job-desc">${authorDescription}</p>
64 <hr />
65 </#if>
66 </#if>
67</div>