Measures of Central Tendency (Contd…) Prepared by: Bhakti Joshi Date: November 28, 2011

Frequency distribution of Weights in Pounds of a sample of packages Weights Class Frequency of packages (f) Mid-point (x)fx 10.0 – ( )/2= 10.51*10.5= – *11.5= – *12.5= – *13.5= – *14.5= – *15.5= – *16.5= – *17.5= – *18.5= – *19.5=

Monthly Average Cash Balances of 600 customers Class (Rupees) Frequency of Customers (f) Mid-point (x)fx 0 – (0+49.9)/2= 2578*25= – – – – – ,

Median …Central Item of a data set (N+1) /2 = M N = Number of observations M= Median

Median Age Intervals Frequency of Mobile Phones Owned (f) Cumulative Frequency Interpretation?

Estimated median weight of the fish caught Weights Intervals Frequency of fish caught (f) Cumulative Frequency Item or number that represents median / 2= 192 nd item Class that contains the median item 70 – 79.5 Width of the weights interval 9.5 Estimated median value? (192 – (181+1) 84 * = 71.13

Mode …Value that is repeated most often in the data set. Mode is not used for ungrouped data Age Intervals Frequency of Mobile Phones Owned (f) Cumulative Frequency Interpretation?

Relationship between Mean-Median- Mode Mean < Median < Mode = Positively Skewed Mean> Median> Mode = Negatively Skewed Mean = Median = Mode = Normal

Positively (right) Skewed Negatively (left) Skewed Normal

Projects Stock Prices of Companies representing any one of the following industries listed on the BSE or NSE Textiles Banking Automobiles IT/Telecommunication Pharmaceutical Foods & Beverages Infrastructure Steel Oil & Gas Chemicals

Project Requirements Select 2 or more stocks of representative industry Stock prices of minimum 100 data points each Background of the representative companies – Names – Industry – Occupation (Trading, manufacturing, distribution, etc) – Products/services – Customers Select statistical tools to compare and analyze the trends and performance of the stocks in the stock market

Website:

Frequency and Distribution Curve

Geometric Mean