Random notes from "Data for ROI and Benchmarking Ebook Collections"

I registered for Library Journals webcast "Data for ROI and Benchmarking Ebook Collections". This webcast can now be viewed On-demand." but as usual couldn't make it but they did record it so - I'm just writing down the points that stuck out for me.

Ying Zhang (Acquistions Librarian from University of Central Florida) did some analysis of her institutions use of ebooks acquired using one of three possible purchase methods. She measured ROI by calculating how many uses ebooks got for each $10 invested in each of the three methods.

Patron Driven Acquisition (PDA) 

Titles acquired based on user demand
2.7 uses/$10

Firm 

Titles selected and acquired individually
0.5 uses/$10

Package

Large pre-defind static collections acquired as one time purchases
4.4 uses/$10

Although this ROI measure makes it look like 'Package' is the best for ROI Ying makes the point that each method has it's place:

1. Package has the highest ROI but is stagnant and use will drop over time. The library and it's users can't weed out unwanted titles or add wanted ones.
2. Firm is how you shape and customise your collection, but has the highest admin costs.
3. PDA provides a low input mechansim by which the collection updates itself to the user's needs.

Michael Levine-Clark Associate Dean for Scholarly Communication and Collections Services University of Denver examined a some global usage data on 340k+ books from EBL from one provider that covered a bunch of libraries.

He found that titles were roughly evenly spread between Social Sciences, Arts & Humanities, and STEM.With Social Sciences having 15% more titles then STEM, which in turn had about 1.5% more titles than Arts & Humanities.

Reverse engineering from his bar chart I get a 'use ratio' for Social Science titles that is 32% higher than STEM titles (in spite of the higher number of titles) which in turn has a 'use ratio' of 15% higher than Arts & Humanities

This is sort of counter intuitive given A&H perceived reliance on monographs, but as Michael continues to look at the stats interesting things pop up:

• STEM titles average far more pages per session (scanning?)
• Arts & Humanities spend the most time per session and per book (immersive reading?)
• His graph by LC number of number of titles available compared to usage shows that L(Education) titles get he most usage followed by N J T H M R D E, Z gradually tailing off with the last 5 classifications being Q P K U and F

He concludes that just using cost per access does not tell the true story of how your resources are being used.