男人资源站-涩涩五月天-加勒比一区二区-欧美丰满少妇-清纯唯美亚洲-蜜臀久久99精品久久久久宅男-1024手机在线观看-a免费在线观看-日韩一区二区三免费高清在线观看-激情欧美一区二区-日韩综合网站-色小说av-夜夜夜操操操-色片在线播放-免费在线观看中文字幕

  • 翰林提供學(xué)術(shù)活動(dòng)、國(guó)際課程、科研項(xiàng)目一站式留學(xué)背景提升服務(wù)！
Home » 國(guó)際課程 » IB課程 » Details

IB DP Maths: AA HL復(fù)習(xí)筆記4.1.3 Frequency Tables

Category: IB課程, 教材筆記, 福利干貨 Date: 2022年7月12日 下午6:49

Ungrouped Data

How are frequency tables used for ungrouped data?

  • Frequency tables can be used for ungrouped data when you have lots of the same values within a data set
    • They can be used to collect and present data easily
  • If the value 4 has a frequency of 3 this means that there are three 4’s in the data set

How are measures of central tendency calculated from frequency tables with ungrouped data?

  • The?mode?is the value that has the?highest frequency
  • The?median?is the?middle?value
    • Use cumulative frequencies (running totals) to find the median
  • The?mean?can be calculated by
    • Multiplying each value?xi?by its frequency?fi
    • Summing to get Σfixi
    • Dividing by the total frequency?n?=?Σfi
    • This is given in the formula booklet
    • Your?GDC?can calculate these statistical measures if you input the values and their frequencies using the statistics mode

How are measures of dispersion calculated from frequency tables with ungrouped data?

  • The?range?is the largest value of the data minus the smallest value of the data
  • The?interquartile range?is calculated by

Exam Tip

  • Always check whether your answers make sense when using your GDC
    • The value for a measure of central tendency should be within the range of data

Worked Example

The frequency table below gives information number of pets owned by 30 students in a class.

 

Number of pets 0 1 2 3
Frequency 11 5 8 6

 

Find

a)? ? ? the mode.

4-1-3-ib-ai-aa-sl-ungrouped-data-a-we-solution

b)? ? ? the median.

4-1-3-ib-ai-aa-sl-ungrouped-data-b-we-solution

c)? ? ? the mean.

4-1-3-ib-ai-aa-sl-ungrouped-data-c-we-solution

d)? ? ? the standard deviation.

4-1-3-ib-ai-aa-sl-ungrouped-data-d-we-solution

 

 

Grouped Data

How are frequency tables used for grouped data?

  • Frequency tables can be used for grouped data when you have lots of the same values within the same interval
    • Class intervals will be written using inequalities and without gaps

How are measures of central tendency calculated from frequency tables with grouped data?

  • The?modal class?is the class that has the?highest frequency
    • This is for equal class intervals only
  • The?median?is the?middle?value
    • The exact value can not be calculated but it can be estimated by using a?cumulative frequency graph
  • The?exact?mean?can not be calculated as you do not have the raw data
  • The?mean?can be?estimated?by
    • Identifying the mid-interval value (midpoint)?xi?for each class
    • Multiplying each value by the class frequency?fi
    • Summing to get Σfixi
    • Dividing by the total frequency?n?=?Σfi
    • This is given in the formula booklet

Exam Tip

Worked Example

a)? ? ? Write down the modal class.

4-1-3-ib-ai-aa-sl-grouped-data-a-we-solution

b)? ? ? Write down the mid-interval value of the modal class.

4-1-3-ib-ai-aa-sl-grouped-data-b-we-solution

c)? ? ? ?Calculate an estimate for the mean height.

4-1-3-ib-ai-aa-sl-grouped-data-c-we-solution

 

 

 

 

轉(zhuǎn)載自savemyexams

? 2025. All Rights Reserved. 滬ICP備2023009024號(hào)-1

國(guó)際競(jìng)賽 國(guó)際競(jìng)賽
了解背提項(xiàng)目
國(guó)際課程 國(guó)際課程
國(guó)際課程
商務(wù)合作 商務(wù)合作
商務(wù)合作
課程試聽 課程試聽