Michael Nunamaker's Modern Impact Values

[so.cal.fan]

Anyone know where to buy a copy?

[Robert Goren]

I might sell mine if I could get out of it what I paid for it. PM me with a price. It ain't cheap and I will be up front, it is not worth the money.

[so.cal.fan]

Thanks, RG
A friend was asking about it.
I'll relay your message to him.
I seem to recall something about it, and it wasn't really good.

[Tom]

http://www.minnow.com/


This is his website, but the books are unavailable.

[garyoz]

I've a copy, but I collect handicapping books and software. Really a pretty useless study of descriptive statistics. Any database could replicate it very easily. Based upon Bris data published in 1994. The "impact value" is not a beta value from a linear regression model, but rather observed values/expected values--(assuming a random outcome when adjusted for field size and PP for the expected value). The other cells in the tables are things like percent of winners, number of starters, etc. Any of the database guys on this forum could replicate the study in a few minutes.

Amazing how primitive things were in 1994, and that seems not too long ago to me. Can't imagine why anyone would want the study except as a collector.

[so.cal.fan]

Do any of you guys use impact values as part of your handicapping?
We were wondering if it was a useful tool?

[garyoz]

Do any of you guys use impact values as part of your handicapping?
We were wondering if it was a useful tool?

First, depends on how you define impact value. Ala Nunnamaker or others. For example, Allways claims to get its impact value through regression analysis.

You can consider "impact values" as "weights" when you are combining variables in predictive models. Most of the handicapping programs use weighted models in some form--usually in calculating a variable such as a power number or similar.

Been discussed ad naseum, search the term "regression analysis" on this Board. Or, search "impact values." Pretty well tread ground. Better off going with an established program IMHO. There are several excellent handicapping programs regularly discussed on this Board.

[trying2win]

SO CAL FAN:

Yes, there are some negative comments here in this thread about MODERN IMPACT VALUES (and to which I agree with on a fair amount of the book). However, I do find a couple of valuable segments in the book...i.e. the parts about the NET ROI stats and IMPACT VALUES for some kinds of turf races and maiden races. Those two positives might make the book worthwhile for someone who cares to do some follow-up research on some more recent races.

The original price of the book was $99.00 U.S. and whatever postage I paid for it. If I remember correctly, many years ago I bought MODERN IMPACT VALUES from the Gambler's Book Shop in Las Vegas.

And yes...I still have that copy of this book in excellent condition (no markings on the pages). If your friend wants it...I'd be willing to sell it for $55 U.S. and I'll pay the postage. I even have a PAY PAL account.

Just send me a PM if your friend is interested.

Thanks,

T2W

[so.cal.fan]

Thanks, you guys,
I'll refer my friend to this thread.
I'll go back and check back threads on this website as Gary suggests.

[Tom]

Do any of you guys use impact values as part of your handicapping?
We were wondering if it was a useful tool?

Definitely talk to Overlay.
I have seen his work and your friend might find it just what he is looking for. I give it a Three thumbs up! :ThmbUp::ThmbUp::ThmbUp: as it was very useful.

[gm10]

Do any of you guys use impact values as part of your handicapping?
We were wondering if it was a useful tool?

It is useful for finding factors which are overbet/underbet. If you find a factor which has reasonably predictive power and an impact value of say 1.1, by all means, use it.

An example I posted here a while ago concerned routes on the Pro-Ride at SA. The IV of turf-to-poly was 0.86 whereas the dirt-to-poly IV was 1.1. Ignore opinions stated as fact - it's IV's like this that will add to your bottom line.

[Tom]

Only if they have a positive ROI.
I have factors that are IV of 2.50 and throw off a loss.

[so.cal.fan]

Tom and others?

Shouldn't IVs be most relevant when considering each separate track, course, and even separate times of the year?

Seems when an IV is thrown out considering all types of races, all times of the racing year, and all tracks....results would not be conclusive?

Tell me if I'm wrong?

[Overlay]

Only if they have a positive ROI.
I have factors that are IV of 2.50 and throw off a loss.

Most individual factors (even ones with high IV's, as you say) will show a loss when taken in isolation (or if they aren't doing so now, they will as they become recognized and overbet). It's using a mix of values from various factors or factor categories, in order to judge composite winning probabilities for horses and combinations, that makes IV's useful for me.

By the way, Tom, thanks for the kind words. :)

[Overlay]

Tom and others?

Shouldn't IVs be most relevant when considering each separate track, course, and even separate times of the year?

Seems when an IV is thrown out considering all types of races, all times of the racing year, and all tracks....results would not be conclusive?

Tell me if I'm wrong?

I've found that, with the proper mix of performance-related factors, making distinctions just on the basis of distance and surface categories (without further breakdown for tracks or seasons) has worked sufficiently well for me. I think that it's when you start breaking out a population too fine that you run into the problem you cite about the results not being conclusive, due to the smaller sample size that you're working with. I prefer a more bulk approach.

[so.cal.fan]

Good enough, Overlay.

I am not familiar with computer studies, except what I read in the DRF or the Racing Digest.

I know Today's Racing Digest publishes stats on winning favorites for the three So.Cal tracks, according to age, distance, sex, surface.
There are some distinct differences.

It's interesting reading, at the least.


I basically follow the same selection quidelines I have developed over the years, but I'm always open to improvement or changes if needed.

I don't make my own morning line (I know a few very successful people who DO make their own morning line, or at least have an idea of the odds they will or will not accept). I simply do not bet favorites. I pass a lot of winners, but in the long run, betting them is just spinning wheels at best and a bit of a loser at worst, it runs in streaks.

[Johnny V]

I bought Modern Impact Values when it first came out and I found it to be very useful at the time and over the years I have referred to it time and time again. It may be a bit dated but still relevant IMO.
OVERLAY'S work in using impact values is I think very well done and would also be very helpful in making up a betting line using impact values for that purpose if you decide to go that route.

[xfile]

I love using impact value as a general source for positive trends. I'm working on a LATE PACE deal right now. Might be skewed severely by all-weather tracks so need separate study. Late Pace extremely high impact value on synthetics. http://www.fullcardreports.com/images208/cbig.gif

[nalley0710]

I have a huge notebook with every probability study and impact value study Ive found or created seperated by factor. They are really great when I have ideas and I want to see what the underlying facts are. My strong suit has always been 5-1 and higher horses. I am a natural contrarian so I can find higher odds wins. Its the 9-2 and below horses that I just traded money on. When I started using oddslines created by impact values described in the book Overlay Handicapping and using those in conjuction with my handicapping and other methods I started finding a lot of lower odds overlays that increased the number of bets and profit I take home. I think that impact values are very effective with lower odds contender seperation. Although they can also be a good tool for verification of the soundness of longshots arrived at by non past performance methods.

[bobphilo]

I might sell mine if I could get out of it what I paid for it. PM me with a price. It ain't cheap and I will be up front, it is not worth the money.

I had always heard that at it was rather expensive, but a worthy follow-up to Quirin's original work on the subject, which represented a great study and true value for the data available at the time.

How refreshing to hear something called good, but over-priced - Nunamaker's Modern Impact Values. I quess it all dependes on what price one puts on scholarly, but expensive research. Perhaps the true answer lies in a truely updated version, or even better, Impact Values based on one's own current statistical data.

Bob

[Donnie]

From Bob:
Perhaps the true answer lies in a truely updated version, or even better, Impact Values based on one's own current statistical data.

Directly from Robot2 in HTR, sorted by Impact Value (this is the last 45 days of one particular track):

http://i584.photobucket.com/albums/ss285/donnie819/IV.jpg

The Robot has to be one of the most powerful, but yet easiest, tools I have ever seen in a handicapping program. ANYONE can pull these types of reports.

You could then test to see if these values have held up over the long haul...test a year or two's worth of data.

[Tom]

Note the positive ROI on work outs as a stand alone factor!

[Donnie]

I would just be careful with that $81 winner in there, Tom. That top item (S/P) gives you plenty of action over the test period. And +15% is nothing to sneeze at. So you get both = Action plus profit!! The proverbial Horseplayer's Dream! LOL

[Donnie]

Tom--
I just tested it. If you throw out that $81 winner, works alone won't carry you. However...here is the S/P for the past 100 days....

http://i584.photobucket.com/albums/ss285/donnie819/VI2.jpg

[Donnie]

So let's tweak this down to just races where the Favorite does not seem overbearing....


http://i584.photobucket.com/albums/ss285/donnie819/VI3.jpg

Averaging a dozen plays a week and no longshot bombs and still turning a nice profit. Mind you, this is ONE track.