ISTANBUL STOCK EXCHANGE (BIST) FELL 6 POINTS IN AVERAGE TODAY THE LATEST SURVEY INDICATES THAT THE PRESIDENT`S APPROVAL RATING NOW STANDS AT 60 PERCENT THE UNITED STATES DOLLAR (USD) APPRECIATED BY 4 PERCENT LAST WEEK AGAINST TURKISH LIRA (TRL). AT THE 95% CONFIDENCE LEVEL, IT IS ESTIMATED THAT THE EXCHANGE RATE WILL BE BETWEEN _____ AND ____.

THE PRICE OF KOC HOLDING STOCK WILL BE HIGHER IN SIX MONTH THAN IT IS NOW THE PRICE OF KOC HOLDING STOCK IS LIKELY TO BE HIGHER IN SIX MONTH THAN IT IS NOW

THE STAGES FOR STATISTICAL THINKING ARE: 1- DEFINE THE PROBLEM 2- DETERMINE WHAT DATA IS NEEDED 3- SELECT A SAMPLE 4- COLLECT DATA 5- SUMMARIZE AND ANALYZE DATA 6- MAKE INFERENCES AND DECISIONS BASED ON INFORMATION

The Journey to Making Decisions Begin Here: Identify the Problem DATA DATA Descriptive Statistics, Probability, Computers INFORMATION Experience, Theory, Literature Inferential Statistics, Computers KNOWLEDGE DECISION MAKING

DATA: Specific observations of measured numbers. INFORMATION: Processed and summarized data yielding facts and ideas. KNOWLEDGE: Selected and organized information that provides understanding, recommendations, and the basis for decisions.

Descriptive Statistics include graphical and numerical procedures that summarize and process data and are used to transform data into information Descriptive Statistics include graphical and numerical procedures that summarize and process data and are used to transform data into information Descriptive Statistics include graphical and numerical procedures that summarize and process data and are used to transform data into information Descriptive Statistics include graphical and numerical procedures that summarize and process data and are used to transform data into information Inferential Statistics provide the bases for predictions, forecasts, and estimates that are to transform information to knowledge

Examples of Populations - Names of all registered voters in TURKEY A complete set of individuals, objects or measurements having common observable characteristics. Examples of Populations - Names of all registered voters in TURKEY - Incomes of all families living in ANKARA - Annual return of all stocks traded on the ISTANBUL STOCK EXCHANGE - Grade Point Averages of all the students in your University - BILKENT

SAMPLE: A subset or part of a population Examples of Samples - Names of 50.000 registered voters in TURKEY - Incomes of 10.000 families living in ANKARA - Annual return of 150 stocks traded on the ISTANBUL STOCK EXCHANGE - Grade Point Averages of 500 students from different departments in your University - BILKENT

Example: Imagine that a public opinion polling firm has been contracted to conduct a study concerning the percentage of the state`s registered voters who approve of nuclear power as an energy source. As part of the polling process, 750 individuals are randomly selected from the voter registration list and carefully interviewed. Elements? Random Sample ? Variable of Interest? Data? Statistic? Population?

Frequency Distribution Example: Marada Inn Above Average Below Average Poor Average Below Average Above Average Average Average Above Average Below Average Poor Excellent

Note: Data is in ascending order. 525 530 535 540 545 550 560 565 570 572 575 580 585 590 600 610 615 625 635 649 650 670 675 680 690 700 715 Note: Data is in ascending order.

Measures of Location Mean Weighted Mean Median Mode Percentiles Quartiles

Sample Mean Sum of the values of the n observations Number of in the sample

Population Mean m Sum of the values of the N observations Number of observations in the population

Weighted Mean where: xi = value of observation i If data is from a population, m replaces x. Numerator: sum of the weighted data values Denominator: sum of the weights where: xi = value of observation i wi = weight for observation i

A wholesaler sold 575, 410 and 520 microwave ovens at prices (in USD) 75, 125 and 100 respectively. What is the mean price of the ovens sold?

Example: The following data represent the duration (in days) of Space Shuttle voyages for the years 1992-1994. (18 values) 8,9,9,14,8,8,10,7,6,9,7,8,10,14,11,8,14,11 Q: Find The Mode

MONTHLY STARTING SALARY (In TRL) Graduate Monthly Starting Salary 1 2,850 2 2,950 3 3,050 4 2,880 5 2,755 6 2,710 7 2,890 8 3,130 9 2,940 10 3,325 11 2,920 12 TOTAL: 35,280