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  • 1.  Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-24-2019 19:15
    Edited by Linda Landon 02-25-2019 07:25
    Hello Everyone,

    I'm venturing into new territory and I have a serious bad case of statistical brain block. 

    I need to analyze whether or not purchasers of large, expensive commercial equipment switch between lenders to finance each new equipment purchase.  

    I have a large dataset comprising multiple unique purchases by a large number of buyers and the cognate lender that financed each purchase.  The data include the type of equipment purchased.  The data range over several years. 

    The goal of this study is to help lenders to obtain an understanding of why equipment purchasers may or may not switch between lenders and what influences the borrowers to choose to switch.

    I'm having trouble devising a mental picture of how to approach this analysis.  Generally, if I read enough, I can get started, but that approach isn't working on this problem. To complicate matters, I can't find published studies related to this in either the peer-reviewed or industry literature), possibly because I'm not using the correct keywords in my search.

    Some of my jumbled thoughts are:
    1. Contingency tables to look at associations between borrower and lender, but that doesn't capture borrowing for equipment over time or whether an earlier borrowing decision affects a later borrowing decision.
    2. Does a previous borrowing decision affect a later borrowing decision.
    3. Does the type of equipment purchased affect the lender decision?
    4. Regression analysis to identify important characteristics that affect the lender choice decision.

    Would anyone care to offer advice or insight on a problem like this?  I'd appreciate any insight you might be able to offer to break my statistical brain block.

    Thanks.

    Linda

    ------------------------------
    Linda A. Landon, PhD, ELS, PRC

    Research Communiqué
    Business, Marketing, & Policy Research

    www.researchcommunique.com
    LandonPhD@ResearchCommunique.com
    573-797-4517

    PhD, Molecular Pharmacology
    Graduate Certificate, Applied Statistics
    Board-Certified Editor in the Life Sciences
    ------------------------------


  • 2.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-25-2019 06:20
    Here's one simple idea: since switching lenders is of interest, make a variable that is 1 if the purchaser switched and 0 otherwise. Then, model the probability of switching via logistic regression.

    Some pros and cons of this approach:

    1. If you have covariates, you can include them to see if they associate with greater or smaller probabilities of switching.
    2. If you have just two entries for each purchaser in your dataset, then you could collapse that into one row in your new dataset, with a 1/0 for whether they switched lenders. If there are more than two entries for a purchaser, then you have to decide how to code the "switched" variable (it is 1 if they switched lenders from the first to the second time, but is it 1 or 0 if they switched back to the original lender on their third purchase?)
    3. If you have more than two entries for each purchaser, then you might consider including "purchaser" as a random effect. This may not matter very much, but it would capture any correlation among responses within particular purchasers. If taking this route, I'd recommend first working through the simpler model that ignores this possible random effect, but then checking to see if the model improves when accounting for this potential correlation.

    Hope this helps.
    Byran

    ------------------------------
    Byran Smucker
    Associate Professor of Statistics
    Miami University
    ------------------------------



  • 3.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-25-2019 20:48
    Bryan,

    Thanks for this advice.   I really appreciate that you took the time to share your insight.

    The idea of logistic regression had occurred to me but I was unsure whether it would be a valid application exactly because of the points that you raise:  There are multiple entries for each purchaser.  In a few cases, there are hundreds of entries for one purchaser.  

    I wonder if it would be possible to view each set of 2 successive transactions as a single observation.   If a purchaser switched lenders between transaction 1 and transaction 2, then that would be coded 1; if not, then it would be coded zero.  If a purchaser switched lenders between transaction  2 and transaction 3, then that would be coded 1; if not, then it would be coded zero.  If a purchaser switched lenders between transaction 3 and transaction 4, then that would be coded 1; if not, then it would be coded zero.  And so on...   A repeated measures analysis, perhaps applying generalized estimating equations, could be applied to these data with the coded response for each new pair of transactions being a repeated measure.  

    Thanks again for your help.

    Linda


    ------------------------------
    Linda A. Landon, PhD, ELS, PRC

    Research Communiqué
    Business, Marketing, & Policy Research

    www.researchcommunique.com
    LandonPhD@ResearchCommunique.com
    573-797-4517

    PhD, Molecular Pharmacology
    Graduate Certificate, Applied Statistics
    Board-Certified Editor in the Life Sciences
    ------------------------------



  • 4.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 14:02
    Yes, Linda, I think using repeated measures in the way you've suggested is a reasonable approach.

    Good luck!

    Byran

    ------------------------------
    Byran Smucker
    Associate Professor of Statistics
    Miami University
    ------------------------------



  • 5.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 15:12
    Thanks, Bryan!

    ------------------------------
    Linda A. Landon, PhD, ELS, PRC

    Research Communiqué
    Business, Marketing, & Policy Research

    www.researchcommunique.com
    LandonPhD@ResearchCommunique.com
    573-797-4517

    PhD, Molecular Pharmacology
    Graduate Certificate, Applied Statistics
    Board-Certified Editor in the Life Sciences
    ------------------------------



  • 6.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 11:00
    Linda,

    First let me state a caveat: I am not intimately connected to this data, nor the question in depth. I have not analyzes the approach nor the data. My response is from a purely theoretical direction.

    W. Edwards Deming published an article in 1975 concerning the difference between enumerative study, and analytic study. Through this article he shows with some mathematical clarity that no matter how accurately we count something, we cannot say anything at all about what 'caused' the count.

    Article:
    https://pdfs.semanticscholar.org/adec/f8c3cc38faec3e11370561e13d89e7499452.pdf
    Semanticscholar remove preview
    View this on Semanticscholar >


    Enumerative vs. Analytic wiki
    https://en.wikipedia.org/wiki/Analytic_and_enumerative_statistical_studies

    Your phrasing of the question, if I read it correctly, shows why you are having difficulty approaching this question. There is no evidence here of a causal nature. No one has been asked 'why' they made a certain choice.

    So, it may be that the best response will be to say that the data does not include any sort of analysis, (of a non-enumerative nature), and thus cannot provide any analysis of 'reasons' for making of the decisions in question.

    -Terry Rosen

    ------------------------------
    Terry Rosen
    BoulderTEC High School
    ------------------------------



  • 7.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 11:11
    Hello Terry,

    I absolutely agree that this analysis can't be causal; at the very "best", it will be associational.   We are still very early in planning how to best use (or not to use) the available data and whether we need to supplement the variables present in our dataset with additional exogenous variables.  

    Slowly, through your advice and the advice of others, I am obtaining a handle on this analysis and breaking through my statistical brain block.  Part of the problem is the inability of our client to state what they want; part of the problem was my statistical brain block.  Right now, I'm somewhat chagrined that the possible paths forward were so obvious but I couldn't seem to see the forest for the trees.

    I appreciate having the Demming article.  I had heard of this article but never had a copy of it previously.  Thanks for sharing it with me.  

    Thanks so much for taking the time to respond.  I deeply appreciate your help.

    Linda

    ------------------------------
    Linda A. Landon, PhD, ELS, PRC

    Research Communiqué
    Business, Marketing, & Policy Research

    www.researchcommunique.com
    LandonPhD@ResearchCommunique.com
    573-797-4517

    PhD, Molecular Pharmacology
    Graduate Certificate, Applied Statistics
    Board-Certified Editor in the Life Sciences
    ------------------------------



  • 8.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 11:32
    Me pleasure.
    I preach this article all the time. I knew 'about' the article for years, and was aware of its implications, and applied it to my practice (teaching).  (Deming references this article in both his lay books. His view at the time was that this issue was conspicuously missing in college texts, and thus statistical practice.)

    I acquired the article years ago, and it took a week of re-reading to realize its implications in depth.

    I suspect you may have a similar realization.

    I've submitted an article for publication to ASQ on their subject.

    Put simply. This single fact delineates the boundary between mere correlation and causation.

    Enjoy

    -Terry

    Sent from my iPhone





  • 9.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 11:06
    Hi Linda

    As a CPA looking at the issue it seems to me there are only  a small number of potential predictor variables that could possibly
    enter into a borrowers decision to switch lenders:

    1. Interest rates. Lower is better for the borrower.
    2. Allowable amortization periods. Longer is better for the borrower.
    3. Loan to value ratios. The higher the allowed ratio is better for the borrower.

    Without even running a regression analysis you can rely on the above variables as the major drivers of borrower decisions.

    Given that the dependent variable is discrete "change" "don't change" it looks like you would have to use some form of logistic regression.

    These three predictor variables will not usually be independent. Most lenders will have a means of classifying borrowers based on overall credit worthiness. Those with higher overall credit scores will have access to lower borrowing rates, longer amortization periods and higher loan to value ratios. It is highly unlikely that each lender will have a one sized set of lending criteria for all borrowers. This being the case data should be stratified based on the lending standards for those borrowers with high credit scores vs. the standards applied to borrowers with low credit scores.

    I hope this helps thinking about the problem.


    Mike Elmaleh

    ------------------------------
    Michael Sack Elmaleh
    Principal
    Michael Sack Elmaleh CPA, CVA
    ------------------------------



  • 10.  RE: Analyzing Switching Business Lenders by Purchasers of Commercial Vehicles

    Posted 02-26-2019 11:21
    Hello Mike,

    Thanks for your feedback.   Identifying these prospective predictor variables and your discusion of their importance is invaluable and I deeply appreciate that you shared it with me.

    I agree that logistic regression is a good candidate analysis.  In particular, using generalized estimating equations to conduct logistic regression has attractive possibilities. 

    There was another interesting suggestion that I'm not sure appeared in the online answers:   Average run length to gauge borrower loyalty.  

    Thanks for taking the time to answer my question.  I appreciate that you did so.

    Linda

    ------------------------------
    Linda A. Landon, PhD, ELS, PRC

    Research Communiqué
    Business, Marketing, & Policy Research

    www.researchcommunique.com
    LandonPhD@ResearchCommunique.com
    573-797-4517

    PhD, Molecular Pharmacology
    Graduate Certificate, Applied Statistics
    Board-Certified Editor in the Life Sciences
    ------------------------------