Survey statistics
 
Category: Survey statistics
Verhulst (1838) developed the logistic growth equation for analyzing the growth of populations. However, his work was ignored and eventually forgotten. Pearl and Reed (1920) developed the logistic growth equation independently and initiated the field of quantitative population ecology. Logistic growth equation later referred to as the "Verhulst - Pearl" growth equation.
1187 days ago
 
The behavior of chromosomes during meiosis and fertilization provides the basis for understanding the inheritance of genes. The combination of meiosis and fertilization results in each offspring having one copy of each gene from his or her mother and another copy of each gene from his or her father. Consequently, children tend to resemble their parents and their siblings.
1187 days ago
 
The cytoskeleton of a cell provides structure, strength, and motility. It provides a cellularscaffolding upon which the cellular organization is arranged. The figure shows a portion of a cell's cytoskeleton. Note that the cytoskeleton is very extensive. Also note that many ribosomes appear to be attached to the cytoskeleton. Polysome refers to two or more ribosomes. The ribosomes attached to the cytoskeleton are often referred to as "free" ribosomes to distinguish them from those ribosomes attached to the nuclear or ER membranes.
1187 days ago
 
The increased knowledge of genes, and of their organization in the genome, has had an enormous impact on medicine and on our perception of human physiology. As Nobel laureate Paul Berg stated presciently at the dawn of this new era:
1187 days ago
 
The study of cell structure includes the fields of CYTOLOGY (for cells) and HISTOLOGY (for tissues), whereas the function of cells is studied in CELL PHYSIOLOGY, BIOCHEMISTRY, and CYTOGENETICS.
1187 days ago
 
Constant Head Permeability • Calculation of seepage through earth dams, embankments of canals, under sheet pile walls. • Estimate settlements in foundations and slope stability analysis.
1187 days ago
 
Nucleotides serve as building blocks for RNA and DNA. Among other important roles, nucleotides can serve as sources of energy (i.e., ATP), physiological signaling mediators (i.e., adenosine in control of coronary blood flow), secondary messengers (cAMP and cGMP), and allosteric enzyme effectors.
1187 days ago
 
Triacylglycerols are the major biological energy source, which are water insoluble. Glycogen is also biological energy source, but it takes a large space to store since glycogen is heavily hydrated
1187 days ago
 
Biochemical Applications: Monitoring blood glucose levels throughout the day is critical to diabetics who need insulin injections. Glucose monitoring devices are based on an assay using the enzyme glucose oxidase which produces gluconate and hydrogen peroxide (H2O2) from glucose. The level of H2O2 in the sample is detected by an indicator dye that is oxidized in a reaction catalyzed by peroxidase.
1187 days ago
 
Monomers are comparatively simple, and include: amino acids (building blocks of proteins) and sugars, phosphates, and bases (building blocks of nucleic acids DNA,RNA) These are not too difficult to make in the lab, and maybe in space (see the table of molecules found in the Murchison meteorite), which is what led to overoptimism about SETI.
1187 days ago
 
Metabolism is the process through which living systems acquire and use free energy to carry out functions. In BICH 410 you learned the composition and structure of biological molecules. In BICH 411, you are going learn the reactions and pathways by which biomolecules are synthesized and degraded.
1187 days ago
 
Normality is a somewhat dated concentration unit that is still encountered in may texts and lab manuals. It has advantages when carrying out titration calculations, however it can be confusing for the uninitiated. Normality is defined as the number of equivalents of solute per liter, and as such, is similar to Molarity.
1187 days ago
 
As has been mentioned, ammonium is toxic, and even small amounts will damage he nervous system. Genetic disorders in ammonium metabolism result in avoidance of high-protein foods and in mental retardation. Ammonium intoxication (e.g., as a result of decreased liver function) can be lethal. As a result, animals must control the amounts of free ammonium that are present, and often use a form organic nitrogen as a waste product. In humans and most other terrestrial mammals, urea is the major nitrogen excretion product. Urea has the advantages of being relatively inexpensive to produce, being soluble in water, and being nontoxic.
1187 days ago
 
Hypothesis testing works a lot like our legal system. In the legal system, the accused is innocent until proven guilty. After examining the evidence, he is found either “guilty” or “not guilty” by a jury of his peers. How much evidence does there need to be to convict? The answer to this is different for every jury. Also, this is not a perfect process – meaning mistakes are made. A mistake can be made by sending an innocent man to prison or letting a guilty man go free. Let’s put these ideas into the framework of hypothesis testing.
1187 days ago
 
An incomplete-block design is resolved if the blocks are grouped into larger blocks and the large blocks form a complete-block design. When natural conditions force us to use small blocks, and hence an incompleteblock design, use a resolved design if possible so that large blocks can be used for management. Of course, this is not possible unless k divides t.
1187 days ago
 
Pascal corresponded with Fermat to develop the laws of probability, and developed Pascal's Wager. He was also a great prose stylist, and pioneered the moder understanding of atmospheric pressure.
1187 days ago
 
The completely randomized design is a design in which treatments are randomly assigned to the experimental units or in which independent random samples of experimental units are selected for each treatment.
1187 days ago
 
associated in a noncausal way with a factor and affects the response (usually found in experiments). Because of the confounding, we find that we can’t tell whether any effect we see was caused by our factor or by the confounding variable – or even both working together
1187 days ago
 
The rows—the observations—may refer to observations at different times, to different subjects, or to different brain locations, depending on the particular analysis. The columns are divided into two sets. One set, denoted by xj are variables describing the condition in which the observation was made. They could be dummy variables describing groups, subjects, or the particular response condition, or they could be other covariates. The second set, denoted by yk are the observed measurements, for example activations measured different locations.
1187 days ago
 
And often I present novice or “keep out of trouble” rules. These are rules that novices should follow to avoid making awful, obvious, knock ’em dead mistakes. And, usually, the Chicago Manual of Style lists 14 pages of exceptions to my rule. Professional book designers shouldn’t follow my “keep out of trouble” rules.
1187 days ago
 
Consider an evolving population where the numbers of individuals in successive generations are of interest. Specically, consider a model which starts, in the zeroth generation, with a single individual who has a random number, X, of o®spring who form the ¯rst generation. Each member of the ¯rst generation, independently, gives rise to a random number of o®spring, with the same distribution as X.
1187 days ago
 
Adaptive trial designs offer many advantages; to realize these advantages requires careful planning in the design phase. The key considerations during the design phase include: • Evaluating the use of a Bayesian vs. Frequentist approach • Determination of an optimized design with pre-specified decision rules • An adaptive algorithm and a simulation model to validate the design in the context of the proposed trial
1187 days ago
 
In many biomedical applications the primary endpoint of interest is time to a certain event. Examples are: time to death; time it takes for a patient to respond to a therapy; time from response until disease relapse (i.e., disease returns); etc
1187 days ago
 
The philosophy of hypothesis testing is that there is some e ect that may or may not be present. If the e ect is not present, then the population parameters satisfy some special equations. If the e ect is present, then these equations no longer hold. The rst case is called the null hypothesis and the second case is called the alternative hypothesis.
1187 days ago
 
To simplify the presentation, we consider the case of time-invariant covariatesX, Y,Z without censoring and without ties. We consider data to be generated by the following hazard rate
1187 days ago
 
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