SKU: 2751602037

The 4PL

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Description

The 4PL(Click on "Preview" below the photo at the left to see inside.) This book explains the mathematical form of the four parameter logistic model that is the basis of many current bioassays. You'll acquire an understanding of how relative potency is estimated by comparing two 4PL models. Youll learn what probits are, why so called probit analysis was once necessary to estimate relative potency, why probit analysis (and "logit analysis") became known as

(Click on "Preview" below the photo at the left to see inside.) This book explains the mathematical form of the four-parameter logistic model that is the basis of many current bioassays. You'll acquire an understanding of how relative potency is estimated by comparing two 4PL models. YouÕll learn what probits are, why so called Òprobit analysisÓ was once necessary to estimate relative potency, why probit analysis (and "logit analysis") became known as Òparallel line analysis.Ó YouÕll also see why some questionable extensions of parallel line analysis are easily manipulated by the bioassayist and should raise the eyebrows of regulatory agencies. YouÕll see why analytic dilution assays are so robust and forgiving of certain mistakes and blunders made by the bioassayist. YouÕll be introduced to historical figures like Trevan, Bliss, Gaddum, Wood, Finney, Jerne, Hill, and others, and you'll appreciate the hard work and deep thinking they did to bring us to where we are today.

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SKU: 2751602037

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DJ McMillian
Dallas, US
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Clean ingredients, Clean skin!
I’ve been using this since 2022 & I’ve been loving it ever since! I really love the exfoliation you get from the scrub & the coffee smell. What really drew me to it was the clean ingredients. My skin feels some much smoother after using this! Only con is how much you get for the price. I think one container only last me 3-5 showers. Im also not the biggest fan of how much oil is in there because I simetimes don’t feel like I’ve gotten all the dead skin off, but it’s under a layer of oil so I have To wash my body again to get that layer of oil off to try to exfoliate and get all the dead skin off. Other than that, it’s a great product!
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colwoo
Dallas, US
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worth buying
refreshing cleans skin
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AJ
Massapequa, US
★★★★★ 3
Oily and can burn
Does make skin smooth and can help with dry skin, but that’s because it leaves an oil on the skin. It can be helped by drying with a towel. It can burn sensitive skin until rinsed. I’ve used it for a couple weeks now. Smells good, but I don’t like the oily texture it leaves and it could moisturize the skin better.
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Rita C. Jones
Grantham, US
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Dead sea body scrub
Style: Grapefruit and Vanilla, Style: Grapefruit and Vanilla
An amazing body scrub. Great natural ingredients, High quality and smells amazing. I'm very pleased with my purchase. Will definitely buy it again. Highly recommend it
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My Rose
Chelsea, US
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Great product for beautiful skin.
Smells really good lather up well, smooth application I use a mesh scrub clothes to exfoliating My skin. been using for 6 months my skin glows it's soft and i have a even skin tone. I am a subscriber never want to run out!🌹
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Reviewed in the United States on December 8, 2025

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