Office a 22 31 21 49 26 42 42 30 28 31 39 39 office b

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Office A: 22 31 21 49 26 42 42 30 28 31 39 39 Office B: 20 37 32 36 35 33 45 47 49 38 28 48 Ex. 2 Below are times obtained from a mail-order company's shipping records concerning time from receipt of order to delivery (in days) for items from their catalogue? 3 7 10 5 14 12 6 2 9 22 25 11 5 7 12 10 22 23 14 8 5 4 7 13 27 31 13 21 6 8 3 10 19 12 11 8 Homework: Day 1: pg 46 – 48 problems 1-5 Day 2: pg 55-58 problems 8-12 and pg 64 – 66 problem 16
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Chapter 1: Exploring Data Section 1.2: Describing Distributions with Numbers Knowledge Objectives: Students will: Explain what is meant by a resistant measure . Give two reasons why we use squared deviations rather just average deviations from the mean. Explain what is meant by degrees of freedom . Construction Objectives: Students will be able to: Identify situations in which the mean is the most appropriate measure of center and situations in which the median is the most appropriate measure. Given a data set: Find the quartiles . Find the five-number summary . Compute the mean and median as measures of center . Compute the interquartile range (IQR). Use the 1.5 × IQR rule to identify outliers. Compute the standard deviation and variance as measures of spread . Identify situations in which the standard deviation is the most appropriate measure of spread and situations in which the interquartile range is the most appropriate measure. Explain the effect of a linear transformation of a data set on the mean, median, and standard deviation of the set. Use numerical and graphical techniques to compare two or more data sets. Vocabulary: Boxplot – graphs the five number summary and any outliers Degrees of freedom – the number of independent pieces of information that are included in your measurement Five-number summary – the minimum, Q1, Median, Q3, maximum Interquartile range (IQR) – IQR = Q3 – Q1 Linear transformation – changes the data in the form of x new = a + bx Mean – the average value Median – the middle value (in an ordered list) Mode – the most frequent data value Outlier– a data value that lies outside the interval [Q1 – 1.5 IQR, Q3 + 1.5 IQR] P th percentile – p percent of the observations (in an ordered list) fall below at or below this number Quartile – multiples of 25 th percentile (Q1 – 25 th ; Q2 –50 th or median; Q3 – 75 th ) Range – difference between the largest and smallest observations Resistant measure – a measure (statistic or parameter) that is not sensitive to the influence of extreme observations Standard Deviation– the square root of the variance Variance – the average of the squares of the deviations from the mean Key Concepts: Measure of Central Tendency Computation Interpretation When to use Mean μ = (∑x i ) / N x‾ = (∑x i ) / n Center of gravity Data are quantitative and frequency distribution is roughly symmetric Median Arrange data in ascending order and divide the data set into half Data are quantitative and frequency distribution is skewed Mode Tally data to determine most frequent observation Data are qualitative or the most frequent observation is
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Office A 22 31 21 49 26 42 42 30 28 31 39 39 Office B 20 37...

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