Presentation on theme: "Coy sumlar. SURVEY OF STATISTICS A survey is an investigation about the characteristics of a given population by means of collecting data from a sample."— Presentation transcript:
SURVEY OF STATISTICS A survey is an investigation about the characteristics of a given population by means of collecting data from a sample of that population and estimating their characteristics through the systematic use of statistical methodology.
SURVEY OF STATISTICS Example: survey of major league baseball players hitting stats who do vs. don’t use steriods.
UNIVARITIVE DATA Data for one variable Example: Travel Time (in minutes): 15, 29, 8, 42, 35, 21, 18, 42, 26 The data is for the variable Travel Time (If you have two sets of data, such as ice cream sales vs temperature, it is called "Bivariate Data")
SURVEY QUESTION Web term: a sentence of inquiry that asks for a reply. Survey questions can be of different types and serve to gather different sets of data. COYS TERM: So basically A QUESTION THAT SIMPLY as for a answer, so its non rhetorical. This question can be put in to many different forms or statements.
SPREAD A measure of spread tells us how much a data sample is spread out or scattered. We can use the range and the interquartile range to measure the spread of a sample. Measures of spread together with measures of location (or central tendency) are important for identifying key features of a sample to better understand the population from which the sample comes from.data samplerange measures of location (or central tendency) population
NATURAL VARIABILITY Variability definition, apt or liable to vary or change; changeable: variable weather; math's. a. an expression that can be assigned any of a set of values... weather events occur in the context of natural variability and the changing climate.
HISTOGRAM histogram is a graphical representation of the distribution of data. It is an estimate of the probability distribution of a continuous variable and was first introduced by 1] A histogram is a representation of tabulated frequencies, shown as adjacent rectangles, erected over discrete intervals (bins), with an area equal to the frequency of the observations in the interval.probability distributioncontinuous variablefrequenciesrectangles
TREATMENT : the way that you think of and act toward someone or something : the way that you deal with or discuss a subject : something that deals with or discusses a subject.
NON-RESPONSE BIAS NON-RSPONSE BIAS occurs in statistical surveys if the answers of respondents differ from the potential answers of those who did not answer.statistical surveys DIRECT DIFFRENCE IN A RESPONSE BIAS!!!!
HYPOTHESIS A statement that is predicted to be true but you run a test to see if it is in fact true or not.
SAMPLING A selection taken from a larger group (the "population") so that you can examine it to find out something about the larger group. For example if a baseball stats analysis who studied all three major parts of baseball (hitting,pitching,fielding) just studied Hitting statistics that would be a example of sampling.
STATISTICAL DATA Bias: Bias is a general statistical term meaning a systematic (not random) deviation from the true value. A bias of a measurement or a sampling procedure may pose a more serious problem for researcher than random errors because it cannot be reduced by mere increase in sample size and averaging the outcomes.