{"id":1275,"date":"2019-10-30T15:17:36","date_gmt":"2019-10-30T19:17:36","guid":{"rendered":"http:\/\/www.foxquestsystems.net\/foxblog\/?p=1275"},"modified":"2020-01-07T09:35:44","modified_gmt":"2020-01-07T14:35:44","slug":"non-overlapping-lags","status":"publish","type":"post","link":"https:\/\/www.foxquestsystems.net\/foxblog\/2019\/10\/30\/non-overlapping-lags\/","title":{"rendered":"Non-Overlapping Lags"},"content":{"rendered":"\n

Generally, in a CPM Network, lag\nvalues should be smaller than the duration values of either its predecessor or\nsuccessor activity.  In other words, lags\nshould not cause gaps in the flow of activities through the CPM network.\nUnfortunately, this is a very easy mistake to make and worse, far more\ndifficult to detect. <\/p>\n\n\n\n

There are 4 possible cases where a\nnon-overlapping lag may occur:<\/p>\n\n\n\n

Case 1: <\/strong><\/p>\n\n\n\n

The Negative Lag is greater than the sum of the Predecessor\u2019s Original Duration and the Successor\u2019s Original Duration (Figure 1).<\/strong> <\/p>\n\n\n\n

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Figure 1<\/figcaption><\/figure>\n\n\n\n

Suppose the Original Duration\n(OD) for Activities \u201cA\u201d and \u201cB\u201d are set to 5 Days each and the relationship is\nset to Finish-To-Start (FS) with a lag of -9 Days. This is overlapping since\nthe sum of the durations of \u201cA\u201d and \u201cB\u201d is 10 Days. <\/p>\n\n\n\n

Now Suppose, the OD for\nactivities \u201cA\u201d and \u201cB\u201d are each reduced to 2 Days. Unless the relationship\nbetween \u201cA\u201d and \u201cB\u201d is changed, a non-overlapping condition will occur (Figure\n1) since the absolute value FS lag of -9 Days is greater than the OD of \u201cA\u201d\nplus the OD of \u201cB\u201d (now at 4 Days). The gap between activity \u201cA\u201d and \u201cB\u201d is now\n5 Days caused by the non-overlapping lag.<\/p>\n\n\n\n

In P6, no Filter that can be\nconstructed to check for this type of Non-Overlapping Lag. <\/p>\n\n\n\n

Z\u00fcmmer Analysis Report #31 \u2013 \u201cNegative\nLag Greater Than Sum of Both Original Durations\u201d identifies the Non Overlapping\nlag condition \u201cNeg Lag > Pred OD + Succ OD\u201d. In the Figure 2 below, each non-overlapping\nrelationship is clearly and individually paired. In addition, the Activity Status\nof the predecessor and successor is listed along with each Original Duration,\nthe type of Relationship and lag value between the two activities.<\/p>\n\n\n\n

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Figure 2<\/figcaption><\/figure>\n\n\n\n

Case 2: <\/strong><\/p>\n\n\n\n

A Positive Finish-To-Start lag is used between 2 Activities (Figure 3)<\/strong><\/p>\n\n\n\n

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Figure 3<\/figcaption><\/figure>\n\n\n\n

Suppose the Original Duration\n(OD) for Activities \u201cA\u201d and \u201cB\u201d are set to 7 Days each and the relationship is\nset to Finish-To-Start (FS) with a lag of -2 Days. This is overlapping since\nthe sum of the durations of \u201cA\u201d and \u201cB\u201d is 14 Days. <\/p>\n\n\n\n

Now suppose the lag value is then\nchanged to +7 Days. The gap between activity \u201cA\u201d and \u201cB\u201d is now 7 Days caused\nby the non-overlapping lag.<\/p>\n\n\n\n

In P6, no Filter that can be\nconstructed to check for this type of Non-Overlapping Lag. <\/p>\n\n\n\n

Z\u00fcmmer Analysis Report #32 \u2013\n\u201cActivities with Finish-To-Start Relationship & Positive Lag\u201d identifies\nthe Non Overlapping lag condition \u201cFS with Positive Lag\u201d. In Figure 4 below,\neach non-overlapping relationship is clearly and individually paired. In\naddition, the Activity Status of the predecessor and successor is listed along\nwith each Original Duration, the type of Relationship and lag value between the\ntwo activities.<\/p>\n\n\n\n

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Figure 4<\/figcaption><\/figure>\n\n\n\n

Case 3: <\/strong><\/p>\n\n\n\n

A Start-To-Start Lag is greater than the Predecessor\u2019s Original Duration (Figure 5).<\/strong><\/p>\n\n\n\n

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Figure 5<\/figcaption><\/figure>\n\n\n\n

Suppose the Original Duration\n(OD) for Activities \u201cA\u201d and \u201cB\u201d are set to 15 Days and the relationship is set\nto Start-To-Start (SS) with a lag of 8 Days. This is acceptable since \u201cA\u201d and\n\u201cB\u201d overlap.<\/p>\n\n\n\n

 Suppose now, the OD for \u201cA\u201d is reduced to 5\nDays. Unless the relationship between \u201cA\u201d and \u201cB\u201d is changed, a non-overlapping\ncondition will occur since the SS lag of 8 Days is greater than the OD of \u201cA\u201d\n(now at 5 Days). The gap between activity \u201cA\u201d and \u201cB\u201d is now 3 Days caused by\nthe non-overlapping lag.<\/p>\n\n\n\n

In P6, no Filter that can be\nconstructed to check for this type of Non-Overlapping Lag. <\/p>\n\n\n\n

Z\u00fcmmer Analysis Report #33 \u2013 \u201cStart-To-Start\nRelationships & Lag Greater Than Predecessor\u2019s Original Duration\u201d identifies\nthe Non Overlapping lag condition \u201cSS Lag > Predecessor OD\u201d. In Figure 6\nbelow, each non-overlapping relationship is clearly and individually paired. In\naddition, the Activity Status of the predecessor and successor is listed along\nwith each Original Duration, the type of Relationship and lag value between the\ntwo activities.<\/p>\n\n\n\n

\"\"
Figure 6<\/figcaption><\/figure>\n\n\n\n

Case 4: <\/strong><\/p>\n\n\n\n

A Finish-To-Finish Lag is greater than the Successor\u2019s Original Duration (Figure 7)<\/strong><\/p>\n\n\n\n

\"\"
Figure 7<\/figcaption><\/figure>\n\n\n\n

Suppose the Original Duration\n(OD) for Activities \u201cA\u201d and \u201cB\u201d are set to 15 Days and the relationship is set\nto Finish-To-Finish (FF) with a lag of 8 Days. This is acceptable since \u201cA\u201d and\n\u201cB\u201d overlap. <\/p>\n\n\n\n

Suppose now, the OD for \u201cB\u201d is\nreduced to 5 Days. Unless the relationship between \u201cA\u201d and \u201cB\u201d is changed, a\nnon-overlapping condition will occur since the FF lag of 8 Days is greater than\nthe OD of \u201cB\u201d (now at 5 Days). The gap between activity \u201cA\u201d and \u201cB\u201d is now 3\nDays caused by the non-overlapping lag.<\/p>\n\n\n\n

In P6, no Filter that can be\nconstructed to check for this type of Non-Overlapping Lag. <\/p>\n\n\n\n

Z\u00fcmmer Analysis Report #34 \u2013 \u201cFinish-To-Finish\nRelationships & Lag Greater Than Successor\u2019s Original Duration\u201d identifies\nthe Non Overlapping lag condition \u201cFF Lag > Successor OD\u201d. In Figure 8\nbelow, each non-overlapping relationship is clearly and individually paired. In\naddition, the Activity Status of the predecessor and successor is listed along\nwith each Original Duration, the type of Relationship and lag value between the\ntwo activities.<\/p>\n\n\n\n

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Figure 8<\/figcaption><\/figure>\n\n\n\n

Copyright \u00a92019 FoxQuest Systems, Inc. – All Rights Reserved <\/p>\n","protected":false},"excerpt":{"rendered":"

Generally, in a CPM Network, lag values should be smaller than the duration values of either its predecessor or successor activity.  In other words, lags should not cause gaps in the flow of activities through the CPM network. Unfortunately, this is a very easy mistake to make and worse, far more difficult to detect. There … Continue reading “Non-Overlapping Lags”<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":1284,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","om_disable_all_campaigns":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[2],"tags":[],"class_list":["post-1275","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-analysis"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.foxquestsystems.net\/foxblog\/wp-content\/uploads\/2019\/10\/Non-Overlapping-Lags-Tag-Screen.jpg?fit=833%2C465&ssl=1","_links":{"self":[{"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/posts\/1275","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/comments?post=1275"}],"version-history":[{"count":3,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/posts\/1275\/revisions"}],"predecessor-version":[{"id":1449,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/posts\/1275\/revisions\/1449"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/media\/1284"}],"wp:attachment":[{"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/media?parent=1275"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/categories?post=1275"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.foxquestsystems.net\/foxblog\/wp-json\/wp\/v2\/tags?post=1275"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}