3032 0 3335 2 3638 0 3941 2 4244 1 4547 1 4850 3 Measures of Central Tendency

# 3032 0 3335 2 3638 0 3941 2 4244 1 4547 1 4850 3

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30–32 = 0 33–35 = 2 36–38 = 0 39–41 = 2 42–44 = 1 45–47 = 1 48–50 = 3 Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Mode The category with the most values is 48-50 with 3 values. Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Mode The category with the most values is 48-50 with 3 values. We can take the mid value of the category to estimate the mode at 49. Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Mode The category with the most values is 48-50 with 3 values. We can take the mid value of the category to estimate the mode at 49. This method of calculating the mode is not ideal as, depending on the categories you define, the mode may be different. Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Mean, Median and Mode for Grouped Data Example 9 The table below gives data on the heights, in cm, of 51 children. Class Interval Frequency 140 h < 150 6 150 h < 160 16 160 h < 170 21 170 h < 180 8 (a) Estimate the mean, (b) estimate the median and (c) find the modal class. Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Solution. (a) To estimate the mean, the mid-point of each interval should be used Class Interval Mid-point Frequency Mid-point × Frequency 140 h < 150 145 6 145 × 6 = 870 150 h < 160 155 16 155 × 16 = 2480 160 h < 170 165 21 165 × 21 = 3465 170 h < 180 175 8 175 × 8 = 1400 Totals 51 8215 Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Solution. (a) To estimate the mean, the mid-point of each interval should be used Class Interval Mid-point Frequency Mid-point × Frequency 140 h < 150 145 6 145 × 6 = 870 150 h < 160 155 16 155 × 16 = 2480 160 h < 170 165 21 165 × 21 = 3465 170 h < 180 175 8 175 × 8 = 1400 Totals 51 8215 Mean = x = 8215 51 = 161 (to the nearest cm) Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M (b) the median is the 26th value. In this case it lies in the 160 h < 170 class interval. The 4th value in the interval is needed. It is estimated as 160 + 4 21 × 10 = 162 (to the nearest cm) . Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M (b) the median is the 26th value. In this case it lies in the 160 h < 170 class interval. The 4th value in the interval is needed. It is estimated as 160 + 4 21 × 10 = 162 (to the nearest cm) . (c) The modal class is 160 h < 170 as it contains the most values. Measures of Central Tendency Sampling Distributions The Sampling Distribution of the Mean The Sampling Distribution of the M Note.  #### You've reached the end of your free preview.

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• Tendency Sampling Distributions, Central Tendency Sampling
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