stats quiz 2 Exam Questions Written With 100% Verified Answers.

The measure of location which is the most likely to be influenced by extreme values in the data set is the - correct answer mean If two groups of numbers have the same mean, then - correct answer other measures of location need not be the same The mean of the sample - correct answer can assume any value between the highest and the lowest value in the sample. When a percentage of the smallest and largest values are deleted from a data set, the mean of the remaining data values is the - correct answer trimmed mean Which of the following provides a measure of central location for the data - correct answer mean In computing the mean of a sample, the value of ∑xi is divided by - correct answer n. mean of a sample - correct answer is computed by summing all the data values and dividing the sum by the number of items. The hourly wages of a sample of 130 system analysts are given below. mean = 60 range = 20 mode = 73 variance = 324 median = 74 the coefficient of variation equals - correct answer 30% The variance of a sample of 169 observations equals 576. The standard deviation of the sample equals - correct answer 24 The median is a measure of - correct answer central location The 50th percentile is the - correct answer median The 75th percentile is referred to as the - correct answer third quartile The difference between the largest and the smallest data values is the - correct answer range the first quartile - correct answer is the same as the 25th percentile. When computing the mean, the smallest value - correct answer can be any value. Which of the following is not a measure of central location - correct answer variance If a data set has an even number of observations, the median - correct answer is the average value of the two middle items when all items are arranged in ascending order. Which of the following is a measure of variability - correct answer Interquartile range The value which has half of the observations above it and half the observations below it is called the - correct answer median The most frequently occurring value of a data set is called the - correct answer mode the interquartile range is - correct answer the difference between the third quartile and the first quartile The weights (in pounds) of a sample of 36 individuals were recorded and the following statistics were calculated. mean = 160 range = 60 mode = 165 variance = 324 median = 170 The coefficient of variation equals - correct answer 11.25% The standard deviation of a sample of 100 observations equals 64. The variance of the sample equals - correct answer 4,096 When the data are skewed to the right, the measure of Skewness will be - correct answer positive When data are positively skewed, the mean will usually be - correct answer greater than the median. Which of the following is not a measure of variability - correct answer the 50th percentile Which difficulty of range as a measure of variability is overcome by interquartile range? - correct answer The range is influenced too much by extreme values When n-1 is used in the denominator to compute variance - correct answer the data set is a sample. The measure of variability that is influenced most by extreme values is - correct answer range The descriptive measure of variability that is based on the concept of a deviation about the mean is - correct answer the standard deviation The numerical value of the standard deviation can never be - correct answer negative The coefficient of variation is - correct answer the standard deviation divided by the mean times 100. The sum of deviations of the individual data elements from their mean is - correct answer always equal to zero. Which of the following symbols represents the size of the sample? - correct answer n The value of the sum of the deviations from the mean, i.e., must always be - correct answer 0 Since the median is the middle value of a data set it - correct answer none of these alternatives is correct. The relative frequency of a class is computed by - correct answer dividing the frequency of the class by the sample size. which of the following is not a measure of variability - correct answer mode If the coefficient of variation is 40% and the mean is 70, then the variance is - correct answer 784 Standard deviation = 8 Coefficient of variation = 64% The mean would then be - correct answer 12.5 A researcher has collected the following sample data. The mean of the sample is 5. 3 5 12 3 2 The interquartile range is - correct answer 6 The following is the frequency distribution for the speed of a sample of automobiles traveling on an interstate highway.