Statistik „ist die Lehre von Methoden zum Umgang mit quantitativen Informationen“ ( Daten ). Sie ist eine Möglichkeit, „eine systematische Verbindung zwischen Erfahrung ( Empirie ) und Theorie herzustellen“. [1] Sie ist damit unter anderem die Zusammenfassung bestimmter Methoden, um empirische Daten zu analysieren . Statistik wird einerseits als eigenständige mathematische Disziplin über das Sammeln, die Analyse, die Interpretation oder Präsentation von Daten betrachtet, andererseits als Teilgebiet der Mathematik , insbesondere der Stochastik , angesehen. [2] [3] [4] Die Statistik wird in die folgenden drei Teilbereiche eingeteilt: Die (auch oder ): Vorliegende Daten werden in geeigneter Weise beschrieben, aufbereitet und zusammengefasst. Die (auch , oder ): In der induktiven Statistik leitet man aus den Daten einer Stichprobe Eigenschaften einer Grundgesamtheit ab. Der Unterschied zwischen und Statistik wird auch an den Fragestellungen deutlich: [5] Amtliche Statistik [ Bearbeiten ]
The Order of Operations: PEMDAS Purplemath If you are asked to simplify something like "4 + 2×3", the question that naturally arises is "Which way do I do this? Because there are two options!" I could add first: ...or I could multiply first: Which answer is the right one? MathHelp.com It seems as though the answer depends on which way you look at the problem. To eliminate this confusion, we have some rules of precedence, established at least as far back as the 1500s, called the "order of operations". A common technique for remembering the order of operations is the abbreviation (or, more properly, the "acronym") "PEMDAS", which is turned into the mnemonic phrase "Please Excuse My Dear Aunt Sally". Parentheses (simplify inside 'em) Exponents Multiplication and Division (from left to right) Addition and Subtraction (from left to right) When you have a bunch of operations of the same rank, you just operate from left to right. Content Continues Below Simplify 4 + 32. Simplify 4 + (2 + 1)2. Simplify 4 + [–1(–2 – 1)]2.
6 BASIC STATISTICAL TOOLS There are lies, damn lies, and statistics......(Anon.) 6.1 Introduction 6.2 Definitions 6.3 Basic Statistics 6.4 Statistical tests 6.1 Introduction In the preceding chapters basic elements for the proper execution of analytical work such as personnel, laboratory facilities, equipment, and reagents were discussed. It was stated before that making mistakes in analytical work is unavoidable. A multitude of different statistical tools is available, some of them simple, some complicated, and often very specific for certain purposes. Clearly, statistics are a tool, not an aim. 6.2 Definitions 6.2.1 Error 6.2.2 Accuracy 6.2.3 Precision 6.2.4 Bias Discussing Quality Control implies the use of several terms and concepts with a specific (and sometimes confusing) meaning. 6.2.1 Error Error is the collective noun for any departure of the result from the "true" value*. 1. * The "true" value of an attribute is by nature indeterminate and often has only a very relative meaning. 6.2.2 Accuracy 6.2.4 Bias 1.
Portal:Statistik aus Wikipedia, der freien Enzyklopädie Willkommen im Portal Statistik Die Statistik befasst sich mit der Gewinnung und Auswertung quantitativer Informationen. Statistische Methoden erklären Gesetzmäßigkeiten bei bestimmten Masseerscheinungen, die aber für Einzelereignisse sonst nicht definiert werden können. Induktive Statistik Empirische Forschungsmethoden
History of Normal Distribution History of the Normal Distribution Author(s) David M. Lane Prerequisites Distributions, Central Tendency, Variability, Binomial Distribution In the chapter on probability, we saw that the binomial distribution could be used to solve problems such as "If a fair coin is flipped 100 times, what is the probability of getting 60 or more heads?" where x is the number of heads (60), N is the number of flips (100), and π is the probability of a head (0.5). Abraham de Moivre, an 18th century statistician and consultant to gamblers, was often called upon to make these lengthy computations. de Moivre noted that when the number of events (coin flips) increased, the shape of the binomial distribution approached a very smooth curve. Figure 1. de Moivre reasoned that if he could find a mathematical expression for this curve, he would be able to solve problems such as finding the probability of 60 or more heads out of 100 coin flips much more easily. Figure 2.
Conflict of interest The presence of a conflict of interest is independent of the occurrence of impropriety. Therefore, a conflict of interest can be discovered and voluntarily defused before any corruption occurs. A widely used definition is: "A conflict of interest is a set of circumstances that creates a risk that professional judgement or actions regarding a primary interest will be unduly influenced by a secondary interest."[1] Primary interest refers to the principal goals of the profession or activity, such as the protection of clients, the health of patients, the integrity of research, and the duties of public office. Related to the practice of law[edit] Judicial disqualification, also referred to as recusal, refers to the act of abstaining from participation in an official action such as a court case/legal proceeding due to a conflict of interest of the presiding court official or administrative officer. Generally (unrelated to the practice of law)[edit] Organizational[edit] Types[edit] Examples[edit]
Free Statistics Programs and Materials by Bill Miller The T-Test The t-test assesses whether the means of two groups are statistically different from each other. This analysis is appropriate whenever you want to compare the means of two groups, and especially appropriate as the analysis for the posttest-only two-group randomized experimental design. Figure 1 shows the distributions for the treated (blue) and control (green) groups in a study. Actually, the figure shows the idealized distribution – the actual distribution would usually be depicted with a histogram or bar graph. The figure indicates where the control and treatment group means are located. What does it mean to say that the averages for two groups are statistically different? This leads us to a very important conclusion: when we are looking at the differences between scores for two groups, we have to judge the difference between their means relative to the spread or variability of their scores. The formula for the t-test is a ratio. SE(XˉT−XˉC)=nTvarT+nCvarC