KIN 4310 1nd Edition Exam 1 Study Guide Lectures 1 8 Lecture 1 January 22 The Scientific Method is an imperfect approach that applies to everything There are three components Measurement Evaluation and Prediction Measurement o This is the act of collecting information and assigning symbols on different ideas upon which a decision is based o Ex VO2 Max HR etc Evaluation o This is when you examine and judge the measurements carefully o Ex Seeing if a diet pill really works Prediction o The act of predicting by reasoning about the future Scientific Knowledge and the three different levels Law the highest level a concise statement of fact that has a huge body of evidence and is generally accepted as true and universal o Ex Boyle s Law o Often an equation Theory the middle level well established explanation of a set of related observations that is based upon solid proof that has been verified many times with just a tad bit of doubt o Ex Big Bang Theory o Can be turned into a law Theory of Relativity is turning into a law Hypothesis the lowest level an educated guess to attempt to explain some basic observations and see if it is true o Hypotheses have to be testable and ethically testable key thing o Hypotheses have to be context specific and declare what population is being talked about Any attempt to measure results is data Data are observations measurements of characteristics behaviors knowledge attitudes survey responses that can be represented by numbers words or symbols Datum is the basis of statistical analyses There are two types Quantitative Data o Deals with numbers o Can be measured Qualitative Data o Deals with descriptions o Can be observed Statistics is an area within mathematics It is a collection of methods for planning experiments obtaining data and then organizing summarizing presenting analyzing interpreting and drawing conclusions based on the data Population is key It is the complete collection of all the elements to be studied A Census is the collection of data from every member of the population This is very difficult to do and is rarely done A Sample is a collection of elements drawn form a subpopulation A bigger sample is better than a small one but a small one will suffice most times A Statistic is a numerical measurement describing some characteristic of a sample A number that represents a characteristic of a sample like the mean standard deviation etc TQ A Parameter is a numerical measurement describing some characteristic of a population TQ Types of Statistics Descriptive Statistics o When you summarize or describe characteristics of a known set of data o Ex When you find the average amount of weight loss in a diet study Inferential Statistics o When you use sample data to make inferences or conclusions or predictions about a sample o Correlational to experimental drugs o Ex When you try to prove disprove a hypothesis o Ex experiments The Center is a representative or average value that indicates where the middle of the data set is located like the mean median and mode Measure of Central Tendency is a value at the center or middle of a data set Mean arithmetic mean o The measure of center obtained by adding the values and dividing the total by the number of values o x bar is the mean of a sample o mu is the mean of a population Median o The middle value when the original data values are arranged in order of increasing or decreasing magnitude o An advantage of median is that it is not affected by an extreme value Mode o The value that occurs most frequently o A data set may be bimodal multimodal or have no mode at all Which measure of central tendency to use o Use mode when data is categorical qualitative o Use median when data contains extreme values that would distort an average o Use mean otherwise Excel Functions o Mean average selection o Median median selection o Mode mode selection Lecture 2 January 27 Variability is a measure of the amount that the values vary among themselves How different scores are from the mean How spread out is the data Are they all close together or all spread out There are three measures of variability range standard deviation and variance Typically the mean and the variability are reported together to describe a distribution Range o The range of a set of data is the difference between the maximum value and the minimum value Standard Deviance o o The standard deviation is a measure of variation of all values from the mean o It is the average distance from the mean o The larger the standard deviation the greater the variability o Outliers have a huge effect on standard deviation o The units of standard deviation are the same as the units of the original data values o Why n 1 Subtracting 1 from n artificially inflates the SD which makes it larger and harder to prove something This means that we want to be more conservative in our estimate of the population Variance o o The variance is the standard deviation squared How does Standard Deviation and Variance differ o Standard deviation is stated in its original units This means its easier to interpret o Variance is stated in units that are squared Excel Functions o Range max selection min selection o Standard Deviation stdev Selection o Variance var selection The Distribution is the nature or shape of the distribution of data like bell shaped uniform or skewed Outliers are sample values that lie very far away from the vast majority of other sample values They can sometimes be an error but it will have a profound effect on the statistic There are different types of Methodological Studies that can be discussed Descriptive Study o How things are o Observes and measures specific characteristics without attempting to modify the subjects that are being studied o Ex One third of the population is obese o These are observational Correlational Study o How things are in relation to other things o Ex Most people who are obese also have comorbid health compromising conditions o These are observational o The observations are not manipulated merely related to each other Experimental Study o How things are and how they got that way o Ex People with an energy imbalance will gain weight and may become overweight or obese o This is hard to do well o This applies some treatment and then observes its effect on the subjects o These are not observational Lecture 3 January 29 Sample Selection should be random Random selection is the best method because it corrects for systematic bias that may confound