# STATS 1

 Population collection of persons, items, or interests"all automobiles" Census Where researches gather data from whole populatin for a given measurement of interest Sample portion of the whole and if properly take, is rep of the whole Descriptive Stats business analyst is usin data gathered on a group to describe or reach conclusions about that same group. Inferential Stats researhers gather data from a sample and uses the stats generated to reach conclusion about the population from which the sample was taken parameter descriptive measure of the population.Greek letters Nominal level lowest level of measurementrepresenting nominal level data used to classify or categorize Ordinal Level measure is higher than nominal. RANK Interval Level measure next to the higest level of data in which the distancecs between consecutive numbers have meaning and the data are always numerical. Ratio Level highest level.height, weight, time, volume Parametric stats require data to be interval or ration. Nonparametric stats analyze interval or ratio data. Ungrouped Data Raw data, or date that have not been summarized in any way Grouped Data data been organized into a frequency distribution. Frequency Distribution summary of data presented in the form of class intervals and frequencies. Range difference between the largest and smallest number Class Midpoint midpont of each class intervalhalfway acoss the class interval and be calculated as the average of the class endpoints. Relative Frequency proportion of the total frequency that isw any given class interval in a frequency distribution.Individul class frequency divided by the total frequency. Cumulative frequency a running total of grequencies through the classes of a frequency distribution. Histogram is a series of contiguous bars or rectangles that rep the frequency of data given class intervals. Frequency Polygon ploted as a dot at the class idpoint and the dots are connected by a series of line segments. Ogive cumulative frequency polygon Dot Plot display continuous , quatative data/ Steam and Leaf Plot seperating the digits are the stem and consist of the higher value digits Pie Chart a circular depiction of data where the area of the whole pie represents 100% of the data and slices of the pie represent and a percentage breakdown of the sublevels. Bargraph Bar chart bars Pareto Chart use this tally to produce a vertical bar chart that displays the most common tyesps of defects, ranked in order of occurence from left to right. scatter plot two dimesional graph plot of pairs of points from numerical variables measure of central tendency yield info about the center, middle part or group of numbers mode the most frequently occuring value in a set bimodal the case of a tie for most frequently, occurring number. multimodal Data sets with more than two modes arthimetic mean the average of a groupe of numbersand is computed by summing all numbers and dividing the number of numbers. measure of varaiablity describe the spread of the dispersion of a set data.Using measures of varability in conjunction with measures of central tendency makes possible a more complete numerical description of the data interquartile range range of values between the first and third quartile.q3-q1` deviation from the mean subtracting the mean from each value of data yields mean absolute deviation MAD average of the absolute values of the deviations around the mean for a set numbers Variance average of the squared deviations about the arthmetic mean for a set of numbers. sum of squares of x sum of the squared deviations about the mean of a set of values standard deviation square root of variance Two ways of applying standard deviation Chebyshevs theorem mean is computed by summing the data values and dividing the number of values Skewness distribution is asymmetrical or lacks symmetry Kurtosis describe the amount of peakedness of a distribution. Lepokurtic distributions that are thin and high Platykurtic distributions that are flat and spread out Mesokurtic normal box and whisker diagram that utilizes the upper and lower quartiles along with the median and the two most extreme values to depict a distribution graphically. A Priori determined prior to the experiment classical method of assigning probablities a process that produces outcomes, and an event, which is an outcomes of an experiment. relative frequency of occurence method the probablity of an event occuring is equal to the number of times the ven has occurred in the past divided by the total number of opportunites for the event have occurred subjective methold assigning probality based onm the feelings inisghts determing the probablity experiment a process that produces outcomes event outcome of an experiment elementary events events that cannot be decomposed or broken down intersection contains the elements common to both sets independent events occurrence or nonoccurrence of one of the events does not affect the occurrence or nonoccurrence of the other event complement elementary events of an experiment not in A comprise its complement mn couting rule probablity four types marginal, union, joint, and conditional Authormonaben20 ID89766 Card SetSTATS 1 DescriptionSTATS 1 Updated2011-06-08T05:56:15Z Show Answers