1 / 9

QBA 260

QBA 260. Chapter 4. Measures of Central Tendency. Statisticians use measures of central tendency as a way of describing data Three common measures of central tendency are: Mean (Average) Median – the middle value in the dataset Mode – the value that occurs most frequently in the dataset.

freira
Télécharger la présentation

QBA 260

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. QBA 260 Chapter 4

  2. Measures of Central Tendency • Statisticians use measures of central tendency as a way of describing data • Three common measures of central tendency are: • Mean (Average) • Median – the middle value in the dataset • Mode – the value that occurs most frequently in the dataset

  3. Calculating an Average • The data are represented by • x1, x2, x3,…, xn • The average is the sum of the data values divided by the number of data values

  4. Calculating an Average • Data: 12, 14, 9, 12, 8 • Sum: 12 + 14 + 9 + 12 + 8 = 55 • n: 5

  5. Excel Functions • AVERAGE • Uses only numbers • AVERAGEA • Treats text as zeroes unless the text is TRUE • TRIMMEAN • Eliminates the most extreme values before calculating the average

  6. Trimmed Average • Deletes the most extreme lower and upper values • 40% trimmed • 1, 2, 3, 4, 5 • 1, 2, 30, 4, 5 • 1, 2, 300, 4, 5

  7. The Median • The median is the value in the middle when the data are ordered • 10, 12, 15, 18, 21, 34, 88 • 10, 12, 15, 18, 21, 34

  8. The Mode • The mode is the most common value • 1, 2, 3, 2, 4, 6, 2, 3, 1, 5, 4

  9. Scales of Measurement • Average • Interval or ratio data • Median • Ordinal, interval or ratio data • Mode • Nominal, ordinal, interval, or ratio data

More Related