Supply and Demand Buying
The Supply and Demand Buying tool provides title-level purchase recommendations based on a user-entered hold wait time. The tool recommends purchase of additional copies of titles that are projected, over the next thirty days, to have a hold wait time longer than the user-entered value. It assists with purchasing decisions for additional copies of titles that already circulate in your library.
The Supply and Demand Buying tool includes the following components:
Initial Filters
You can set the following filters to configure this tool:
Location
The Location filter options reflect the branch locations recognized by your library system. The data is limited to the Owning Locations you select. You can select any number of available locations, but you must select at least one to run the tool. The default is All Locations.
Locations
To determine the location, Decision Center first identifies the location code (shelf code) in the item record. The system then looks up the location code in the Locations Served file and uses the associated branch location code. (For more information on the Locations Served table, see the Sierra WebHelp or the Millennium Innovative Guide & Reference.) The descriptive name associated with the branch location code comes from the Branches file. (For more information on the Branches table, see the Sierra WebHelp or the Millennium Innovative Guide & Reference.) If the system cannot find the location code or the branch name in the Locations Served file, Decision Center displays the location code that appeared in the item record.
Physical Format
Limits the data to the physical formats you select. You can select any number of available formats, but you must select at least one to run the tool. The default is All Physical Formats.
The Physical Format filter options reflect the formats configured on the Physical Format page of the Decision Center Admin section.
Collection
Limits the data to the collections you select. You can select any number of available collections, but you must select at least one to run the tool. The default is All Collections.
The Collection filter options reflect the collections configured on the Collection page of the Decision Center Admin section.
Wait Time Greater Than (Days)
Limits the results to items with a projected wait time that exceeds the specified number of days if no additional copies are purchased.
Data Columns
The following data columns appear in the results:
Title
The title, taken from the title field of the bibliographic record. Each title entry links to the corresponding Title Details page.
Author
The name of the author, taken from the author field of the bibliographic record.
Each author's name is a link to the Author Details page.
Call Number
The call number from the item record. If the item record call number does not exist, Decision Center uses the call number from the bibliographic record.
First Item Created
The date on which the first item record was created for a title.
Hold Queue
The number of holds currently in the queue.
Current Hold Wait Time
The number of days required to satisfy a hold placed "now" using the number of copies currently owned. The calculation excludes non-holdable items.
Wait time is, approximately, the quotient (in days) of the hold queue divided by Monthly Supply. The actual algorithm used by Decision Center is substantially more complex.
Item Count
The number of copies currently owned by the library.
Items with excluded item statuses are excluded from all reports and tools except cross-tab reports and budget reports. See Exclude Item Status for more information.
On Order Copies
The number of copies on order.
Monthly Supply
Average monthly supply for the title.
Supply is the potential number of copies that can be checked out per month. Decision Center assesses the library's historical circulation turnaround time for each I TYPE and location pair to establish a "read modifier" (per-copy monthly availability) value. For example, a title with an average circulation period of 20 days would have a read modifier value of 1.5. The system multiplies this value by the number of available items to establish the monthly supply.
Decision Center calculates turnaround time on a per-title basis when sufficient data exists for the title. The number of available items includes items on order, but does not include items unavailable for circulation, such as "lost" copies or copies withheld from circulation.
Items on Order
If, in the initial filters, you limit the tool to any subset of "all locations", the supply count includes all copies on order for the complete library system. Decision Center cannot anticipate how the library plans to distribute orders. Including all copies on order prevents the application from making a recommendation to over-buy.
Item-level Filters
Filters to item-level criteria, such as Format in I TYPE, cause the tool to include any title with even a single item that matches the filter value.
Monthly Demand
Demand for the title over the last 30 days.
Demand is the number of holds and checkouts (minus holds filled, and not including renewals) over the specified time period. Demand is calculated title by title, not by item.
Price per Copy
The per-copy price of the item.
Decision Center analyzes payment information from Sierra or Millennium to determine the per-copy cost. If such information is not available, it uses the PRICE field from the item record.
If you specify a different price, Decision Center uses the new price when you apply the remedy filters.
Copies to Buy
The number of copies to buy based upon tool calculations.
Click the lock icon to prevent Decision Center from changing the specified Price per Copy and Copies to Buy values for the row. Locked rows are not affected when you change other values and apply the remedy filters.
Projected Hold Wait Time
The number of days required to satisfy a hold placed 30 days from "now" assuming the immediate addition of the number of copies indicated in the Copies to Buy column, thus increasing the projected Monthly Supply. The calculation excludes non-holdable items.
Wait time is, approximately, the quotient (in days) of the hold queue divided by Monthly Supply. The actual algorithm used by Decision Center is substantially more complex.
Extended Amount
The total cost of the recommended purchase, that is, the list price times the number of copies to buy.
The floating Extended Amount Total box shows the sum of all amounts in the Extended Amount column.
Remedy Filters
You can apply the following filters to modify the results:
First Item Created Before
Limits the results to titles with the first attached item created before the specified date.
Demand Greater Than
Limits the results to items with monthly demand greater than the specified number.
Purchase Amount
Limits the results to the specified amount as the maximum total expenditure.
