# Math 231

 the science of collecting, describing, and interpreting data statistics a collection, or set, of individuals, objects, or events whose properties are to be anazlyzed population a subset of a population sample a characteristic of interest about each individual element of a population or sample variable the value of the variable associated with one element of a population or sample. Data value(may be a number, a word, or a symbol) the set of values collected from the variable from eachof the elements that belong to the sample data a planned activity whoe results yield a set of data experiment a numerical value summarizing all the data of an entire population parameter a numerical value summarizing the sample data statistic a variable that describes or categorizes an element of a population qualitative variable a variable that quantifies an element of a population quantitavive variable a qualitative variable that characterizes an element of a population. nominal variable arithmetic operations are not meaningful for data, and an order cannot be assigned to categories nominal variable a qualtiative variable that incorporates an ordered position, or ranking ordinal variable a quantitative variable that can assume a countable number of values discrete variable can assume any values corresponding to isolated points along a line interval...there is a gop between any two values discrete variable a quantitative variable that can assume an uncountable number of values. continuous variable can assume any value along a line interval, including every possible value between any two values continuous variable a sampling method that produces data that systematically differ from the sampled population biased sampling method a list, or set, of the elements belonging to the population from which the sample will be drawn sampling frame samples that are selected on the basis of being judged "typical." judgment samples samples in which the elements to be selected are drawn on the basis of probablility probability samples a sample design in which the elements of the sampling frame are treated equally and there is no subdividing or partitioning of the frame. single-stage sampling a sample selected in such a way that evvery element in the population or sampling frame has an equal probability of being chosen simple random sample a sample in which every kth item of the sampling frame is selected, starting from a first element, which is randomly selected from the first k elements systematic sample a sample design in which the elements of the sampling frame are subdivided and the sample is chosen in more than one stage multistage random sampling a sample obtained by stratifying the population, or sampling grame, and then selecting a number of items from each of the strata by means of a simple random sampling technique stratified random sample a sample obtained by stratifying the population, or sampling frame, and then selecting a number of items in proportion to the size of the strata from each strata by means of a simle random sampling technique proportional stratified sample a sample obtained by stratifying the population, or sampling frame, and then selecting some or all of the items from some, but not all, of the strata cluster sample graphs that are used to summarize qualitative data. circle graphs or bar graphs show the amount of data that belong to each category as a proportional part of a circle circle graph show the amount of data that belong to each category as a proportionally sized rectangular area bar graph a bar graph with the bars arranged from the most numerous category to the least numerous category. It includes a line graph displaying the cumulative percentages and counts for the bars pareto diagram the pattern of variability displayed by the data of a variable distribution displays the frequency of each value of the variable distribution displays the data of a sample by representing each data value with a dot positioned along a scale dotplot display displays the data of a sample using the actual digits that make up the data values stem and leaf display a listing, often expressed in chart form, that pairs values of a variable with their frequency frequency distribution a bar graph that represents a frequency distribution of a quantitative variable histogram 1. a title, which identifies the population or sample of concern 2. a vertical scale, which identifies the frequencies in the various classes 3. a horizontal scale, which identifies the variable x histogram a frequency distribution that pairs cumulative frequencies with values of the variable cumulative frequency distribution a line graph of a cumulative frequency or cumulative relative frequency distribution ogive 1. a title, wich identifies the population or sample 2. a vertical scal, which identifies either the cumulative frequencies or the cumulative relative frequencies 3. a horizontal scale, which identifies the upper class boundaries agive the average with which you are probably most familiar. mean the value of the data that occupies the middle position when the data are ranked in order according to size median the number exactly midway between a lowest valued data, L, and a highest valued data, H. midrange the difference in value between the highest valued data, H, and the lowest valued data, L range a deviation from the mean is the difference between the value of x and th mean x bar. deviation from the mean the mean of the absolute values of the deviations from the mean mean absolute deviation the mean of the squared deviations sample variance is the positive square root of the variance sample standard deviation Authorskyesr2005 ID68411 Card SetMath 231 Descriptiontest 1 Updated2011-02-23T17:10:25Z Show Answers