Chapter 1

• 1. StatisticsChapter 1

2. Statistics status, census as a science a collection, organization,presentation, analysis, andinterpretation of data6/30/2012 2 3. Descriptive Statistics Includes anything Answers questions such done to data which is as designed to Who Who performed better in the entrance examination?summarize or describes, without What are the highest andgoing any further, thatWhatlowest scores obtained bystudents in the test?is without attempting What is the most populatedto infer anything thatschool in Metro Manila?goes beyond the dataHow many students arethemselves.Howinterested to take Statisticsonline?6/30/2012 3 4. What are the Roles and PrincipalObjectives of Descriptive Statisticsas a Scientific Discipline What kind of data to be collected? How much data need to be collected? How should we organize the data? How should we interpret the data?6/30/20124 5. Most Pinoys Believe in Love at First Sight(Source: Philippine Daily Inquirer, February 15, 2002)According to the survey made by the Social Weather Stations(SWS) in November, MAJORITY of Filipinos believe in love at first sightand say each person has only one true love. Belief in love at first sight ishigher among middle-aged and older Filipinos compared to youngerones, and higher among Filipinos with less education. Compared to aFebruary 2000 Gallup poll in the United States, the SWS survey foundthat more Filipinos believe in love at first sight (72% compared to 52%among Americans), have experienced falling in love at first sight (64%compared to 40% among Americans), and believe in one true love (84%compared to 74% among Americans). When asked about their pastrelations, SWS found that 70% of Filipino men have experienced fallingin love at first sight, as compared to only 58% of Filipino women. Sixty-seven percent (67%) of married Filipinos are more likely to say theyhave experienced falling in love at first sight, compared to 54% of singleFilipinos.The SWS said it surveyed 1,200 adults. The results have a 3%margin of error.6/30/20125 6. Terms Used in Statistics PopulationParameterPopulation - is the set of measurementscorresponding to the entire collectionWe may wish toof units about which the information issought.draw conclusions- is the group of objects about which about the recoveryconclusions are to be drawn.rate of 4000 collegeParameterstudents by studying- is any numerical value whicha sample of 300describes a populationstudents from theSamplepopulation.- the set of measurement that areactually collected in the course of theinvestigation.- is the portion of the subset of objects Sampledrawn from the population.6/30/20126 7. Population Parameter Sample A typical televisionWe may wish tonetwork surveys uses a draw conclusionsample of 2000 about how Metrohouseholds and the Manilans vote in theresults are used to form coming presidentialconclusions about thepopulation of all election by studying26,000,000 householdsa sample of 1000in the country.persons from this population.parameter not indicated6/30/2012 copyright 2006 www.brainybetty.com ALL RIGHTS 7 8. Classification of Dataare attributes which cannot beQUALITATIVEsubjected to meaningfularithmetic. 1) color of the eye Qualitative Variables- measure a quality3) position in an organizationor characteristics on each 5) Rate of politician (e.g. excellent)individual or object, 6) state of our forestdistinguished by somenonnumeric characteristics. QUANTITATIVEare numerical in nature andtherefore meaningful 2) number of computers in a roomarithmetic can be done.4) number of students enrolled in NEUQuantitative Variables 7) temperature in Baguio City - measure a numerical 8) amount of time to finish the testquantity or amount on eachindividual or object.9) scores in exam6/30/2012 8 9. QUANTITATIVE - assume exact- assume the infinitelyvalues only. It can assume many values corresponding toonly a finite or countable the point on a line interval innumber of values. Decimals such a way that there are nohave no meaning. gaps or interruptions. Decimals have meaning.DISCRETE CONTINUOUS2) number of computers in a room 7) temperature in Baguio City4) number of students enrolled in 8) amount of time to finish the test NEU9) scores in exam6/30/2012 9 10. Scales of MeasurementNOMINAL ORDINAL-categorical INTERVALRATIO -names, labels, or categorized1) The different only1) sizes of t-shirtsstudents (e.g. small) do -numbers1) honor oforganization not meanstudents1) length of movies2) The survey 2) rating of anything2) ranking in a 2) number of votespolitician (e.g.responses of yes,contestpoor)no or undecided-numerical-numerical -categorical-numbers are-numbers are-categorical -numbers are used used to labelused-names, labels, -differencesand categorize and rank -differencesbetween databetween dataonly -differences values are between data values are-numbers dontmeaningfulmeaningfulmean anythingvalues are meaningless-no zero-have zero6/30/201210 11. ACTIVITY NO. 2 Prof. Amelia F. Asaytonocopyright 2006 www.brainybetty.com ALL RIGHTS6/30/2012RESERVED.11 12. Activity No. 1bA restaurant wants to get feedback from its 1000 customer on the quality of food andservices it offers. Below is a sample of the survey questionnaire that they distribute totheir 100 customers.Using the sample survey, identify at least five variables that you can classify asQUANTITATIVE or QUALITATIVE. For QUALITATIVE VARIABLE, determine if it isNOMINAL or ORDINAL. For QUANTITATIVE VARIABLE, determine if it is RATIO orINTERVAL and DISCRETE or CONTINUOUS. Name: Quality of Food _____________________________________VS _____S_____US Age: _____________ Gender:Serving Size _________________ _____VS _____S _____US Nutritional Orientation Services ____ Vegetarian ____ Non-vegetarian _____VS _____S _____US How often do you go to this restaurant? ____ once a weekVS - Very Satisfactory ____ twice a weekS - Satisfactory ____ more than twice a week US - Unsatisfactory ____ others What type of orders do you usuallyRemarks/Comments/Suggestions: take? __________________________ ____ solo meals ____ group meals__________________________ ____ combo meals ____ ala carte6/30/2012 12 13. ReferencesHigh School Statistics by CampeaBasic Statistics with Probability by Hernandez Elementary Statistics by BlayIntroduction to Probability and Statistics by CalingasaPowerPoint Lay-out www.brainybetty.com6/30/201213