CJUS-K300 1nd EditionExam # 1 Study Guide Lectures: 1 - 5Lecture 1 (August 25)Simple Random Sample Steps- Obtain a list of all members of the population- Number all items/participants on the list- Decide on your desired sample size (n)- Select numbers from a random number table or generator until desired sample size is obtained. Systematic Random Sample Steps- Obtain a list of all members of the population- Number all items/participants on the list- Decide on your desired sample size (n)- Select one random number from a random number generator. (Eg. 10)- Select every (10th) number from the list until the desired sample size is obtained. Random sampling is always:- Known: Each persons’ probability is known ( ex. 10% chance of being chosen)- Equal: Each person has the same known probability of being selected.- Independent: Each person has no effect on another or their chance of being selected. Lecture 2 (August 27) Levels of Measurement- Nominalo All inclusiveo Mutually exclusive; each case must belong to only one groupo No inherent order for the groups. Ex. Sex – M/F or F/M, the order it’s presented makes no difference- Ordinalo All inclusiveo Mutually exclusiveo Ordered but distance between two adjacent categories may vary. (Likert scalewithout numbers)- Interval and Ratioo All inclusiveo Mutually exclusiveo Ordered but there are equal distances or interval between any two adjacent categories Interval: Likert scale with numbers below, zero is arbitrary (does not mean an absence, ex. Temperature) Ratio: Zero has a meaning which refers absence Lecture 3 (September 3)Calculating rates – divide the frequency by the number of people in the population (f/N)Calculating standardized rates – multiply each rate by either 10 ,100,1000, 10,000 + with the purpose of transforming your rated in to numbers which do not begin with a decimal. Ratios are simply a means of comparing two entities. Ex. If there were 90 arrests for DUI and 30 for theft then the ratio to compare the two would be 3:1. Proportion – divide the category frequency by the total (n/N)Percent – simply multiply the proportion by 100Lecture 4 (September 8)Range – the difference between the least and the greatest value for a variable. - Example: 10, 9, 3, 11, 4, 13o Range = 13-3 or 10 points differenceMode – the most frequently occurring value for a variableo Mathematically the value most likely to be picked at random from the data set. o Bimodal = two modes, tri-modal = three modes, no modeo Can be used with any level of measurement, but doesn’t always representthe data wellMedian – the midpoint value in a rank-ordered data set. First, rank order the data then determine the middle most value. If there are three data points, it’s the number in the 3rd position, if there are four data points then the median is the value in the 2.5th position meaning adding the two middle most points together and dividing by 2.Mean – The average of the data set. Adding all the data together and dividing it by the number of data points. For population data – sum of x / N, for sample data – sum of x / n. Lecture 5 (September 10)Variance: A one number summary of how spread out the values for a variable are, taking into account every value for the variable.These formulas will be given to you on the exam but you should know how to calculate them, make sure you review order of operation, PEMDASVariance for population dataP.E.M.D.A.SP - ParenthesisE – ExponentsM/D – Multiplication and DivisionA/S – Addition and SubtractionEquation sheet will be given out before the exam. DON’T FORGET YOUR