# whoknows

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1. ## Dependent variable bias? Strong correlation between baseline value and change over time.

Prometheus, Thank you for taking the time. That is what the columns mean indeed. Incidence rates are calculated per 1,000 live births. The numbers are probably correct. They are from the WHO website. The test is to describe the correlation between changes in vaccination rates and changes in measles incidence (2nd-3rd column). The first column is added to show the correlation between baseline measles incidence and incidence changes over time. Given the fact that this correlation is much stronger than the one between vaccinations and measles incidence, I was wondering how justified it is to adjust for baseline incidence when we look a the relation between changes in vaccination and measles incidence during follow-up. I was thinking an effect from vaccinations would have to remain relevant when it is added as the second independent variable (next to baseline measles incidence) in a regression model. With changes in measles incidence as the dependent variable.
2. ## Dependent variable bias? Strong correlation between baseline value and change over time.

Prometheus, thank you for your reply I find it difficult to explain what I mean. Therefore, it would be better if I added my correlations. A bit of text is added to the Excel file where I try to explain what I mean. Hope this makes it more clear. question scienceforum.xlsx
3. ## Dependent variable bias? Strong correlation between baseline value and change over time.

Hello people, Using PSPP, I was doing some basic linear regressions. Examining the following correlation: I included data from over a 100 countries and looked at both baseline values and values 15 years later. Calculating the differences in value for both the independent and dependent variable. Plotting them in a graph. Results were as follows: A weak R-squared value which was highly significant nonetheless (P = < 0.0001). With a negative trendline. No confounding was detected from other variables. I found a "strong" correlation between baseline values of the dependent variable and it's successive changes in values during the 15-year follow-up period. The R-squared values was > 0.7. There was a positive correlation: Higher changes during follow-up were related to higher baseline values. My problem is as follows: Most values for the dependent variable dropped over the 15-year follow-up period. When I added baseline values for the dependent variable to the model, there was no noteworthy correlation left between the independent- and dependent variable (P for sig: > 0.50). Would it be correct to assume the negative correlation between independent- and dependent variable were (probably) caused by the strong correlation between the 2 values for the dependent variable? Subgroup analyses of the correlation between the independent- and dependent variable after 15 years showed the following: -Decreases in values for the independent variable were not linked to changes of the dependent variable. -Increases in values for the dependent variable were not linked to changes of the independent variable. .
4. ## How was protein synthesized from amino acids in the prebiotic world?

Don't give me this. Which of the questions in my opening post has been answered? Show me. Who is more ignorant? The person answering a question or the person insisting the question has been answered, but who is unable to answer the question when asked? So we agree we don't have an answer to any of the questions in my opening post? Finally. For this resets the starting point: We allready knew it is impossible to form protein under plausible early Earth conditions. But the lack of answers to my questions shows we don't even have a valid theory for how it could have occurred. Which hypotheses exist for any (part) of the 3 points I made?
5. ## How was protein synthesized from amino acids in the prebiotic world?

If there were a logic explanation, why can't my simple and 100% valid questions (from a scientific perspective) be answered? My questions are derived from scientific logical thinking. And is there any logic if it goes against all we know about basic Chemistry? You are kidding me. You have no idea whatsoever how any of these can be explained: ​1) Formation of protein, carbohydrates, fatty acid vesicles under plausible prebiotic conditions. 2) The formation of any single component of a cell. 3) The formation of a cell and the interaction between the different parts of it. So you've explained "everything" except for this. Tell me what is left. What has been explained according to you? And by explained I mean what can scientists create under plausible early Earth conditions? So explain to me what has been experimentally created under plausible prebiotic conditions. The basic starting point is the complex mixture of thousands of different molecules formed under simulated early Earth conditions. Please explain how we go from here. For this is your basic setting. Quit the nonsense about ignorance/dishonesty for you don't have a clue how to go from here. Not a single clue. Prove me wrong and show me how we go from the complex mixture to a protein. Everybody agrees. I am just showing there is no experimentational evidence proving the way we got here.
6. ## How was protein synthesized from amino acids in the prebiotic world?

So which molecules do the clay "things" select? And what does that mean? Does the clay attach to a specific molecule or does the clay only let specific molecules enter the clay? Which molecules would that be? Does clay chiralise things? To what extent? The micellular formation idea has exactly the same drawbacks as the idea that protein could have been formed by amino acids on early Earth. Energy added to molecules in the early atmosphere would not only form tiny amounts of amino acids, but also tiny amounts of carboxylic/fatty acids. Again: surrounded by thousands of other types of molecules. Not only amino acids but also carboxylic acids can only form chains in high concentrations of almost pure mixtures of the molecules needed to form the chain. This would prohibit formation of fatty acid vesicles. What does a theoretical increase in the possibility of synthesizing smaller molecules have to do with the odds that any specific molecules will be selected for inclusion in a chain of molecules? I don't see an answer to any of the questions I ask. All that is given are theories about how molecules could have been attached to one another in order to form chains. Nothing has to do with the way unneeded molecules would be eliminated from a complex mixture of thousands of diferent molecules. I don't state our laws would be sufficient. That's part of my points. Scientists explain abiogenesis using the laws we know. These laws (at least for now) reject the possibility abiogenesis could have occurred using the explanations given to date. Being life formed from simple chemicals under the conditions examined. If current experimentation and observation rejects the idea. The idea should not be educated and we should be honest: Teaching people/children we don't have the slightest idea how abiogenesis occurred.
7. ## How was protein synthesized from amino acids in the prebiotic world?

What exactly is your point? Does it answer any of my questions or disprove anything I state in post #47? If so, please explain that. Do you see what you are doing here? First you state: "You should not make assumptions like that. You are using your 'knowledge' from current chemistry to debunk something that happened billions of years ago in an environment which is mostly unknown." But then you ignore this statement by telling me how DNA probably evolved on an early Earth. We don't know the atmosphere on early Earth. But we do know the amino acids arose from a carbon source (CO, CO2 or CH4), a hydrogen source (H2 or H2O), and a nitrogen source (N2 or NH3). I don't see any substantial differences in experimental molecules created by these sources. Quantities of molecules and their diversity may differ. But all experiments produce a large mixture of different molecules in tiny quantities when exposed to an energy source. From that perspective, my question would be: Is there any reason to assume basic Chemistry would have been under differential natural laws on the early Earth? I agree with you that quantum mechanichs may create a better picture of what happened. Not will, but may.
8. ## How was protein synthesized from amino acids in the prebiotic world?

Reading seems to be very hard for you people. Again: where did I state I am a creationist? A scientists evaluates both the strengths and weaknesses of a hypothesis, before accepting them as a probable theory. This is exactly what I am doing.
9. ## How was protein synthesized from amino acids in the prebiotic world?

"There is no point sticking his head in the sand though". I a merely showing the flaws in the hypothesis. Flaws not disproven by any of you. So who is sticking his head in the sand then? "There are explanations out there that seriously alter the values put on those probabilities he has waving about." What is keeping you form pointing them out. Your remark with possible clay catalysts has nothing to do with the chance probabilities of which molecules are included when 100 molecules are lined up to form a chain consisting of 100 different molecules, does it?
10. ## How was protein synthesized from amino acids in the prebiotic world?

The 1x 10 and other probabilities are as they are. Clays have nothing to do with the odds. Even if the clays would somehow catalyze reactions, how would they influence what molecule binds to the amino acid? Your remark has to do with the conditions I mentioned in #47, not with the chance probabilities one specific amino acid will bind to another molecule. That's all you can do, is it not? Giving stupid remarks without being able to answer any of my questions. And without disproving any of the points I am making. I have respect for people who want to discuss the topic. But less so for people who are here to flame others.
11. ## How was protein synthesized from amino acids in the prebiotic world?

Life "formed" by chemicals under early Earth conditions has nothing to do with my personal beliefs. The sum of Chemistry and statistics disproves it. This is something else. Of course, I applaud experiments to see how life first began. But scientists will have to take a different approach.
12. ## How was protein synthesized from amino acids in the prebiotic world?

I am not giving an alternative. But hanging on to a "hypothesis" that goes against basic Chemistry and statistics seems nonsensical to me.
13. ## How was protein synthesized from amino acids in the prebiotic world?

I think you are missing the point. In theory, amino acids are assumed to join. But this is not observed in the primary experiments where complex mixtures of thousands of different molecules are formed in micromolar concentrations. The mixture does not (practical experiment) and cannot (in theory) by any means form protein because a) the non-amino acids disrupt the process, b) water hydrolyzes any potentially formed peptides, c) reactive molecules take the place of amino acids in the chain, or end the chain, and d) there are requirements for the availability and amount of energy needed to form the chain. If you were somehow able to form a short peptide chain (5-6 amino acids), it would be available in minuscule amounts (nanomol/L), and it would be a racemic mixture of left- and righthanded amino acids in a soup of other molecules. Again, I ask the question: Is there any place on Earth where we could drop amino acids to show their synthesis to protein? Do you understand the required environmental conditions, I pointed out? The origin of DNA and RNA is well understood? Do you know how their building block could be formed and synthesized under prebiotic conditions? It is the same as with the protein. Some pyrimidines/purines will be formed in micromolar amounts together with thousands of other different molecules under early Earth conditions. The same goes for carboxylic acids assumed to have been the basis for a fatty acid vesicle (aka a primitive cell). They will not link to a chain, for they cannot form a chain. And yes, the pyrimidines/purines will also be a racemic mixture. Check what I wrote about protein. The same goes for the other complex building blocks.
14. ## How was protein synthesized from amino acids in the prebiotic world?

Incorrect. I am saying the abiotic model used to explain life originating from chemicals fails.
15. ## How was protein synthesized from amino acids in the prebiotic world?

Where did you get those ideas? I am saying chemistry does not allow protein synthesis from the abiotic early Earth model. Not by any tiny plausible chance. People don't seem to understand the conditions needed for protein synthesis to take place and don't know what the results from early Earth chemical experiments mean. But how can they be blamed if the scientists themselves make unrealistic assumptions and publish their results as if there were any proof for possible abiotic cell formation. Let's say that we want a fairly simple protein, 100 amino acids long and built from 10 different amino acids. Regardless if we want that specific protein to be formed, or if we want to calculate the odds that one duplicate protein from a fictional existing protein could be formed. The odds would be calculated as 1 x 10​100 , which allready is a very small number. An estimate for the total amount of atoms on Earth is 1,33 x 10​50. Showing the odds for it happenning on Earth are allready pretty much nonexisting. People than refer to the Universal probability bound which is defined as: "A degree of improbability below which a specified event of that probability cannot reasonably be attributed to chance regardless of whatever probabilitistic resources from the known universe are factored in" The estimated number for the bound is 1 x 10​150 . A chance smaller than this would be unreasonable to assume to be possible anywhere, ever in the known Universe. But the number 1 x 10​100 for the protein synthesis gives a much higher chance you say? You could say protein synthesis under these assumptions would be unlikely, but could possibly happen somewhere in the Universe. And that somehwere would happen to be planet Earth? But the chance of 1 x 10​100 of the specific required protein to be formed is totally unrealistic. ​​Early Earth experiments show that: 1) Racemic mixtures of amino acids are formed. 2) Amino acids are formed in a liquid mixture in the presence of thousands of other molecules. All in tiny (micromolar) concentrations. 3) Other reactive molecules (unneeded amino acids, amines, and carboxylic acids) containing a -NH2 or -COOH group are formed in quantities higher than the amino acids. A ratio of 3:1 for other reactive molecules to amino acids has been published. Possibly 3x in amount and in different forms. The racemic mixture doubles the amount of different amino acids available --> 20 x 10​100 = 1.27 x 10​130 different proteins possible. The presence of 3x as much other reactive molecules gives us 40 different possibly reactive molecules. This number becomes 80 doubled in the racemic mixture. --> 80 x 10​100 = 2.04 x 10​190 different molecules possible using a chain of only 100 parts. A number trillions and trillions of times smaller than the Universal probability bound. You may argue the calculations and number used. And say the number should be smaller. Let's assume some flaws in the reasoning. Say you downplay the number to a chance of "only" one in 1 x 10​100 . Then I would ask you what the odds would be for the formation of only 2 identical proteins. It would be the product of the number used: 1 x 10​200 . Or I would ask what the odds would be for a protein found in a living cell, consisting of all 20 amino acids in a chain of 1,000 amino acids. The chance would be unimaginably small. And we only would be talking about one single protein. Including one additional protein decreases the odds of formation by the product of these chances. And a living cell can include thousands of different proteins. Each different protein adds the product of it's chance of formation. The odds of a thousand different wanted molecules formed under the conditions mentioned would be a 1,000 x the product of 1 x 10​100 , or a chance of 1 in 1 x 10​100000 . Non-peptide bonds. Various molecules can react with the wanted protein by forming non-peptide bonds. In thas sence, the amount of possible reactive molecules is much larger than given in the examples above. Including these numbers (I have no idea how large), will most probably dramatically increase the diversity of the potentially created molecules in a 100-part molecule. The chance of obtaining the wanted protein decreasing by the same order of magnitude. The environmental conditions for a protein to be formed, further decrease the odds dramatically, by multiples of orders of magnitude. Many conditions would need to be met for protein synthesis: -The continuous presence of the needed amino acids at the right time and place. This would be hindered to a large extend by the sheer presence of the thousands of types of other (non-reactive) molecules synthesized in prebiotic experiments. -The a) continuous presence of b) the right amount of energy needed to form peptide bonds. -The (near) absence of water. -The correct pH, heat and possibly mineral content or unknown other environmental factors. This is the reason I asked if anybody knows one single place on Earth where amino acids can be dropped, in response to which we could observe protein synthesis. I doubt that such a place exists. Summary: the odds of one single simple protein built from 10 different amino acids in a chain of 100 amino acids. In a prebiotic Earth experiment mixture it is the product of these three chances: a) One in 2.04 x 10​190 . b) The chance of formation of non-peptide bonds. c) The chance of finding a location where amino acids can readily form proteins. We are talking about a simple protein which is not even folded the right way to become biologically active. A protein which is supposed to remain stable under various conditions. What these numbers show: There is not even the tiniest of a plausible chance protein could have been synthesized from the raw building blocks supposedly available on the early Earth.
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