1996 SLD Shift Policy

Shift Structure:

We will continue to staff all shifts with: As in the previous runs we will staff the Liaison shift during the day and swing shifts, and provide one person per day for a (typically off-site) off-line shift.

Following last run's success, the Expert and Non- Expert shifts will be offset with respect to each other by 4 hours. The three Expert shifts and two Liaison shifts will be:

          Owl:      00:00 to 08:00
          Day:      08:00 to 16:00
          Swing     16:00 to 24:00.
The three Non-Expert shifts will be:
          Owl:      04:00 to 12:00
          Day:      12:00 to 20:00
          Swing     20:00 to 04:00.
All shifts will be taken in consecutive blocks of 3 or 4 days: The Expert weekday block will begin with the Monday day shift (08:00- 16:00), while the weekend block will end with the Monday owl shift (00:00-08:00).
The Non-Expert weekday block will begin with the Monday day shift (12:00-20:00), while the weekend block will end with the Monday owl shift (04:00 - 12:00).

Collaborators will be assigned to one or more of the shift types (Non- Expert, Expert, Liaison, Run Coordinator, Off-line). No one will be declared an expert without non-expert shift experience and training!

In addition, each collaborator will be assigned a weighting factor that will increase or decrease the number of shifts assigned. The default weighting factor is 1.0. All graduate students will be assigned a weight of 2.0 until they are in the process of writing their dissertation. Individuals may ask to be assigned a higher weighting factor if they wish; the advisors of graduate students may request a higher weight for their students if they feel it is desirable.

Shifts will be assigned through a scheduling program that uses as its input availability lists provided by members of the collaboration who expect to sign physics papers that include data from the run in question. Details of the procedure for specifying availability is provided on the SLD shift page.

Some relevant features of the availability lists are as follows:

The program will enforce the block structure and attempt to EQUALIZE per collaborator:

subject to the constraints of the availability list, personal weight factors, and packing factor.

It is recognized that financial constraints may require an individual to serve his/her shifts for the entire run in a block. The sign-up program has a field where the user may indicate that they want their shifts packed together as densely as possible. Collaborators desiring maximum packing would indicate such & those not desiring that the shifts be packed together will leave the field blank.

After shifts are assigned, it is the PERSONAL RESPONSIBILITY of the shiftee to trade shifts he/she cannot attend. Off loading assigned shifts is -not- allowed. A master list will be maintained in the CEH and all changes must be made on it. Shifts should only be traded as shift blocks.

We are planning for a 23 week run and will assign shifts in one block in the first week of Nov.


The Run Coordinators will assign collaborators to the Expert, Non- Expert, Run Coordinator, Liaison, and Off-line shift categories. They will assign weighting factors to each person. These assignments will be publicly available and open to amendment by consultation with the RCs.

The Shift Czar will continue to be Terry Schalk, who will operate the program and serve as a contact person. He will not help collaborators trade shifts.

The Shift Policy Committee did disband itself when the '94 run began. Thereafter, the Run Coordinators, under the leadership of the Shift Czar, have taken responsibility for the success of the run. The Shift Czar and Run Coordinators will continue to hold fortnightly meetings to review procedures, developments, changes of shift type assignment, etc. The RC group will provide guidance to respond to changing run conditions.

Run Coordinators:

The Run Coordinator pool will be limited to about 20 people; only 1-2 weeks of RC duty will be required of each during the 6 month run. To make sure that each RC is up-to-date on the current state of the experiment, he/she will be scheduled for one block of non expert shifts in the week preceding his/her RC tour of duty.

The "8:00 AM Daily Report" to SLC aspect of the RC's job should be de- emphasized. Counts of Zs on tape from STATUS are adequate for the daily report with a weekly reporting of hard numbers. We urge that the RC role stress monitoring of data quality, education of less-trained shiftees, and expertise for times of problems.


Turning Non-Experts into Experts and Experts into "True Experts" is very difficult. General assembly classes for all shiftees before the run are deemed to be of limited usefulness. Hands-on training is the best way to learn. To that end, anyone that needs training will be assigned by the chift czar to a Run coordinator. S/he will provide and/or oversee the training. In addition, documentation will be periodically reviewed and updated via the RC and/or commissioning meeting.

On one will be assigned expert shifts until s/he has taken non-expert shifts and received proper training. Declaring all grad students to be "experts" independent of their training was considered to be a real problem in the beginning of the '94 run. However, ALL graduate students are expected to BECOME experts before future runs. This will be critical if there is a long '97-'98 run.

Estimated shift blocks/category:

As a rough guide to the anticipated shift block load for the '96 run we will use the following guesses... there are approximately

          23  weeks in the run  (optimistic estimate)
	 158  shift blocks for experts (only experts for the first 4 weeks)
          96  shift blocks for non experts (RC's take 1 block per week)
          92  shift blocks for Liaison
	  18  Run Coordinators  or  1+ RC weeks and 1 non expert shift block
	  45  Experts           or  3+ expert shiftblocks per weight 1 expert
	  29  Liaison           or  3+ liaison shift blocks
	  80  non experts       or  1+ non expert shift blocks


We feel that insisting that shifts be served in blocks is the best way of addressing the level of competence and data quality issues. The system is constantly changing; it is better to learn it once and use it before it changes again. Instituting a scheduling program that enforces the block structure and eliminates claims of unfairness and unavailability seems to be the best solution. The voluntary system is partially accommodated by allowing "preferred" shift blocks. The concept of shift points was generally recognized to be ineffective in fairly distributing shift loads. In the current plan we will try to equalize the discomfort as much as possible.

Clearly, collaborator cooperation in this scheme switches from a willingness to sign up for shifts to a willingness to enter availability data. As the existing publication policy prevents SLD management from using it to achieve compliance, shift availability will be defaulted to AVAILABLE. Collaborators will be socially ostracized and hassled by the Shift Czar and management if they decide not to participate in the system.

Any scheduling program needs some flexibility in order to function. On the other hand, each collaborator's flexibility will vary according to his/her place of residence, teaching schedule, or personal requirements. These can both be accommodated by requiring each collaborator to make himself/herself available for a minimum number of shifts. After much discussion, we settled on a minimum required availability of 20% for all collaborators, resident at SLAC or not. It is hoped that physicists whose schedules are not highly constrained will make themselves available for a larger percentage of shifts and limit their use of PREFERRED availability.

A poll was taken of SLC EOICs to determine if there is a need to continue Liaison shifts. Their unanimous desire was to keep the status quo. The small size of the pool and the perceived problem of its sociological composition will be addressed by requiring that Liaison shifts be filled in the same manner as the other shifts.

Discussions with Richard Dubois resulted in a decision to keep the Off- line shifts organized as they were during the previous run. Physicists will be cross referenced for that pool as well so that the system may assign them. However, no points will be awarded for these shifts; they will in effect become service work.

There was a strong agreement that ALL graduate students need to be more involved with the detector that collects the data used for their dissertations. The decision to push all graduate students to become Experts and to assign them twice the nominal shift load are the steps that were taken in that direction. The Advisory Group felt that even these steps were inadequate; advisors who feel their students will profit from greater participation may apply to have their weights or responsibilities increased.

We feel that the Run Coordinator pool needs to be welded into an effective quality control team that recognizes the changing needs and conditions of the experiment. A good model is that of the SLC Program Deputies. All RCs need to keep current of the SLD situation; the pool should be small enough and its members expert enough that they form a group that is recognizable, has the respect of shiftees and SLC operations, and can deal with any reasonable questions that might be asked. They should review the SLD status on a fortnightly basis and either institute or eliminate procedures as required.

Terry Schalk
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