# Determine the rush hours for providing sufficient

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Determine the rush hours for providing sufficientequipment
SummaryPeople make many estimations in almost all events around them in a daily life. Some of theseestimates may not turn out to be true or are closed to the actual value.The side effects of such estimations may be from none to severe consequences depending on thetype of parameters of the populations the estimation is made for. There are two kinds ofestimates: a point estimate and an interval estimate. People use estimations for the mean andproportion of a population most of the times.Key TermsEstimationEstimation is a procedure for inferring the value of an unknown given population property orcharacteristic based on observations from a random sample that is drawn from the population.Interval EstimateAn interval estimate is a range of probable values for a population parameter.Point EstimateA point estimate is a single value that represents the best guess of the true value of a populationparameter.PopulationThe population is all possible individuals or items to which a statistical analysis will be applied.Population and Sample MeanIntroductionPopulation mean is one of the most important parameters of a population and is calculated mostof the times. The mean of a population is unknown most of the times if not always. Therefore, arandomly selected sample(s) from the desired population estimates the true value of thepopulation mean with regard to our interest. Sample mean is more consistent than any othermeasurements of central tendency such as median and mode.Learning Material
inferential statistics is used to estimate the true value of a population mean. Population mean isobtained from a correspondent sample taken from the population.The Greek letter (mu) represents the population mean or average. This mean is calculated byadding all of the observations of the interested characteristic within the population and thendividing the result by the total number of observations in the population. Again, the Greek letter(Upper case sigma) represents the summing or adding all of the observations associated to acharacteristic of interest. The equation of a population mean is given by:whereNrepresents the size of the population andrepresents the individual value of theobservations of interest. Obviously, the value of subscript “i” is limited between 1 (the firstobservation in the population) to , the size of population (last observation in the population).As it was mentioned earlier, the population mean is usually unknown. Therefore, a typicalrandom sample(s) is selected from the population to estimate the population mean.The equation for the sample mean is exactly the same as the one for the population mean withthe exception of using for the size of the sample instead ofNrepresenting the size of thepopulation. Also,is chosen as mean of the sample instead of, mean of population. Nowcalculate the mean of the following random sample having data values of {2, 4, 8, 10, and 11}.

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