I BITRON RATINGS 1350 Avenue of the Americas MADELEINE H. SCHREIBER - PDF document

I BITRON RATINGS 1350 Avenue of the Americas MADELEINE H. SCHREIBER New York, New York 10019 Manager 1OTELEVI8IONCABLE R Radio Representative/Network Sales (212) 887-1324 April 10, 1986 To: Bruce Hoban - Republic Radio Re: Arbitron Radio Weighting Presentation Enclosed is a copy of the Arbitran presentation on Radio Weighting that was done at the March Radio Advisory Council meeting. Please call if you have any questions about the presentation. Sincerely, MHS:eo Enc. @D ARBITRON RATINGS COMPANY a Control Data Company www.americanradiohistory.com

J g2) CONTROL DATA PRIVATE RADIO WEIGHTING RADIO ADVISORY COUNCIL MARCH 1986 CLAIRE KUMMER ARBITRON RATINGS J www.americanradiohistory.com

Q 9 CONTROL DATA PRIVATE -TAB SAMPLE? WHY WEIGHT THE IN RETURNED SAMPLE NOT IN PERFECT PROPORTION TO THE UNIVERSE DIFFERENT BEHAVIOR PATTERNS AMONG DIFFERENT SEGMENTS OF THE UNIVERSE ARBITRON RATINGS f nQo.o"2: RACCMAKMMÉR -1 www.americanradiohistory.com

@D CONTROL DATA PRIVATE RETURNED SAMPLE NOT IN PROPORTION TO UNIVERSE... SAMPLE FRAME DIFFERENTIAL USABILITY. CONSENT. RETURN THAT CAN'T BE PERFECTLY FORECASTED AND/OR CONTROLLED UP FRONT DISPROPORTIONAL SAMPLING ARB1TRON RATINGS D Dô `J RAC/MARCH 86 -2- C. KUMMER www.americanradiohistory.com

DIFFERENT BEHAVIOR PATTERNS AMONG DIFFERENT o UNIVERSE SEGMENTS: GEOGRAPHY AGE SEX ETHNICITY ARBITRON RATINGS 2 2M [20 D RAC/MARCH 86 -3- C. KUMMER www.americanradiohistory.com

I g9 CONTROL DATA PRIVATE WHAT IS SAMPLE BALANCING? A MEANS OF WEIGHTING SURVEY DATA TO A SET OF o CONTROLS WHICH YIELDS THE LEAST EXTREME IN WEIGHTS FOR APPLICATION TO EACH INTERVIEW WEIGHTING IS PERFORMED 'ON THE MARGIN," RATHER THAN TO EACH INDIVIDUAL CELL ARBITRON RATINGS J RAC/MARCH 86 C. KUMMER -4- www.americanradiohistory.com

I (s9 CONTROL DATA PRIVATE WHY IS IT IMPORTANT TO KEEP THE WEIGHTING TO THE LOWEST LEVEL POSSIBLE? BECAUSE WEIGHTING LOWERS THE EFFECTIVE SAMPLE BASE - THERE IS A TRADE-OFF BETWEEN REMOVAL OF BIAS - AND MAINTENANCE OF ESB. WEIGHTING CONTROLS THAT ARE "TOO TIGHT" MAY PRODUCE SUCH EXTREME WEIGHTS THAT THEY PUSH TOG MUCH "BOUNCE" INTO THE RESULTS - THE BIAS REMOVAL FUNCTION THEY PERFORM CAN - BECOME ACADEMIC. ARBITRON RATINGS D DO RAG/MARCH 86 -5- C. KUMMER www.americanradiohistory.com

9 CONTROL DATA PRIVATE SOME SAMPLE BALANCING TERMS MODEL - ONE COMPLETE SET OF DATA UPON WHICH SAMPLE BALANCING IS PERFORMED EXAMPLE: MODEL 2 MODEL 1 -METRO NON METRO TOTAL SURVEY SURVEY AREA AREA ARB1TRON RATINGS J RAC/MARCH 86 C. KUMMER -6- www.americanradiohistory.com

Q D CONTROL DATA PRIVATE TERMS MARGINAL - A CHARACTERISTIC CHOSEN FOR USE IN WEIGHTING A MODEL; EACH WEIGHTING CHARACTERISTIC WITHIN A MODEL IS A DIMENSION EXAMPLE: ONE SEX/AGE MARGINAL SEX" AGE TWO z l I I I MARGINALS I SExJÄG'c THREE MARGINALS 1 1 Ill nu 1 i 1 ARBITRON RATINGS J n/%1[ATIT RAC/MARCH 86 C. KUMMER -7- www.americanradiohistory.com

g2) CONTROL DATA PRIVATE TERMS CLASS A SPECIFIC, DEFINED SUBSET OF A GIVEN - MARGINAL EXAMPLE: SEx'.GE 1 iii! ARBITRON RATINGS j o, n/% -[-Z RAC/MARCH 86 -8- C. KUMMEk www.americanradiohistory.com

lig21 CONTROL DATA PRIVATE TERMS THE COMBINATION OF CLASSES FROM TWO OR CELL - MURE MARGINALS SEXteGE EXAMPLE: II I 11/7-/'i//ì / SEX:AGE / 7 / i 7 11111 11111 ARBITRON RATINGS RAC/MARCH 86 C. KUMMER -9- www.americanradiohistory.com

I Q 9 CONTROL DATA PRIVATE HOW DOES SAMPLE BALANCING WORK? ASSUME A MODEL MADE UP OF TWO MARGINALS WITH TWO CLASSES EACH SEX ARBITRON RATINGS D Dô RAC/MARCH 86 -10- C. KUMMER www.americanradiohistory.com

ig9 CONTROL DATA PRIVATE MARGINAL DATA MARGINAL CLASS -TAB IN POPULATION SEX MEN 50.000 25 WOMEN 75 50,000 TOTAL 100 100,000 COUNTY 60 90.000 B 40 10.000 A TOTAL 100,000 100 CELL DATA POPULAT ION -TAB I N --'+ SEX------+ SEX MEN WOMEN T 41 15 45 90 60 sal 149 S - 10 10 30 40 1 9 50 50 25 75 ARB1TRON RATINGS EM 0 RAC/MARCH 86 -11- C. KUMMER www.americanradiohistory.com

9 CONTROL DATA PRIVATE ADJUST FIRST MARGINAL TO' CONTROL FIGURE BY CALCULATING 1. A WEIGHT FOR EACH CLASS CONTROL CLASS WEIGHT = -TAB IN SEX 15 P 145 COUNTY 10 A 30 -TAB IN 25 75 CONTROL 50 50 WEIGHT CL45S 2.0 0.67 ARBITRON RATINGS L RAC/MARCH 86 -12- C. KUMMER www.americanradiohistory.com

9 CONTROL DATA PRIVATE NOW MULTIPLY THE IN -TAB IN EACH CELL BY ITS CLASS 2. WEIGHT SEX 15 x 2.0 45 x .67 B COUNTY A 10 x 2.0 30 x .67 SEX B COUNTY A 50 50 -TAB IN 50 50 CONTROL PAeEzzd-a5e ARBITRON RATINGS j Co) RAC/MARCH 86 C. KUMMER -13- www.americanradiohistory.com

Q9 CONTROL DATA PRIVATE ADJUST SECOND MARGINAL TO CONTROL FIGURE BY 3. CALCULATING A WEIGHT FOR EACH CLASS SEX CONTROL WEIGHT IN -TAB, B 60 1.5 90 COUNTY A 40 10 .25 -TAE 50 1N 50 CONTROL 50 50 ARBITRON RATINGS J RAC/MARCH 86 -14- C. KUMMER www.americanradiohistory.com

I QD CONTROL DATA PRIVATE NOW REPEAT STEP 28 MULTIPLY THE 'IN 4. -TAB" IN EACH CELL BY ITS CLASS WEIGHT SEX MEN WOMEN 30 x 1.5 30 x 1,5 B COUNTY A 20 x ,25 20 x .25 SEX MEN -TAB CONTROL WOMEN IN 45 90 90 45 B COUNTY 10 10 5 5 A 50 50 -TAB IN 50 50 CONTROL ARBITRON RATINGS RAM RAC/MARCH 86 -15- C. KUMMER www.americanradiohistory.com

Q 9 CONTROL DATA PRIVATE TEST FOR 'CONVERGENCE' THE FIRST 'PASS' IS COMPLETE. 5. -TAB AND CONTROL MARGINAL BY COMPARING ADJUSTED IN VALUES FOR AGREEMENT. IN THIS SIMPLE EXAMPLE, AGREEMENT WAS REACHED IN ONE THIS IS USUALLY NOT THE CASE. PASS. ARBITRON RATINGS 2 RAC/MARCH 86 C. KUMMER -16- www.americanradiohistory.com

@D CONTROL DATA PRIVATE RESULTS MARGINAL (RIM) WEIGHTS: 2.0 MEN WOMEN .67 1.5 B .25 A CELL WEIGHTS ARE CALCULATED BY MULTIPLYING THE RIM WEIGHTS ASSOCIATED WITH EACH CELL: S EX 3.0 ii- 1.0 .17 .5 SAMPLE BALANCING IS COMPLETE. ARBITRON RATINGS 2 RATira,RAC /MARCH 86 C. KUMMER -17- www.americanradiohistory.com

9 CONTROL DATA PRIVATE TO CALCULATE THE PPDV FOR EACH CELL: 1. CALCULATE THE AVERAGE PPDV: TOTAL POPULATION AVERAGE PPDV = TOTAL IN -TAB 100,000 1,000 = 100 2. CALCULATE CELL PPDV: AVERAGE PPDV X CELL WEIGHT = CELL PPDV SEX M E r 3,000 i2 1,000 500 170 EACH USABLE DIARY TAKES ON THE CALCULATED PPDV FOR ITS CELL. ARBITRON RATINGS j RACCMAKU1M86 www.americanradiohistory.com

cg 2s CONTROL DATA PRIVATE COMPARISON OF CELLS FOR THE POPULATION AND THE WEIGHTED IN -TAB: POPULATION SEX MEN WOMEN 49,000 41,000 90,000 10,000 9,000 1,000 50,000 50,000 WEIGHTED IN -TAB SEX WOMEN MEN 45,000 } 90,000 45,000 0 5,000 5,000 10,000 50,000 50,000 MARGINALS AGREE...CELLS DO NOT BECAUSE WE DID NOT WEIGHT ON THEM. ARBITRON ATINGS D RACCMAKUMM$R -19- www.americanradiohistory.com

(g 2i CONTROL DATA PRIVATE HOW DOES ARBITRON APPLY SAMPLE BALANCING? 1. GEOGRAPHIC WEIGHTING UNIT: USUALLY INDIVIDUAL COUNTIES 2. SEX AND AGE IN 16 GROUPS: WOMEN MEN 12-17 12-17 18-24 18-24 25-34 25-34 35-44 35-44 45-49 45-49 50-54 50-54 55-64 55-64 65* 65; 3. RACE/NATIONALITY: BLACK/OTHER HISPANIC/OTHER BLACK/HISPANIC/OTHER ARBITRON RATINGS } KQ D,ED RAC/MARCH 86 -20- C. KUMMER www.americanradiohistory.com

(g 9 CONTROL DATA PRIVATE HOW DOES ARBITRON APPLY SAMPLE BALANCING? MODELS ARE USUALLY MAJOR GEOGRAPHIC REPORTING AREAS: METRO NON-METRO/NON-TSA ADI NON-METRO/NON-A.DI TSA OTHER USES OF MODELS: RACE/NATIONALITY (WHERE SAMPLE SIZE IS LARGE ENOUGH) "EMBEDDED" METROS ARBITRON RATINGS RAC/MARCH 86 -21- C. KUMMER www.americanradiohistory.com

g CONTROL DATA PRIVATE CALENDAR WEIGHTING -- CONTROLLING FOR DIFFERENTIAL RETURNS BY MONTH -WEEK SURVEY PERIOD WILL -WEEK PERIOD OF A 12 EACH 4 BE CONTROLLED TO REPRESENT ITS FAIR ONE-THIRD SHARE OF THE TOTAL CALENDAR WEIGHTING WILL BE ANOTHER MARGINAL AND o WILL ADD ANOTHER DIMENSION TO EACH MODEL: 5 / r - II IIÌI TWO , i.iiuri DIMENSIONS iiwii sii iiii,viwni iv1 AJn-/ THREE DIMENSIONS I ARBITRON RATINGS j RAC/MARCH 86 C. KUMMER -22- www.americanradiohistory.com

(2 9 CONTROL DATA PRIVATE WEIGHTING LOWERS ESB...HOW MUCH WILL THIS ADDED WEIGHTING FOR CALENDAR TIME LOWER ESB? A VERY SMALL AMOUNT -- WE ESTIMATE LESS THAN 51 FOR MGST REPORTING AREAS ARBITRON RATINGS RAC/MARCH 86 -23- C. KUMMER www.americanradiohistory.com

(g 2i CONTROL DATA PRIVATE WHAT IMPACT WILL THIS HAVE ON REPORTED ESTIMATES? MINIMAL... SAMPLES FAIRLY WELL -DISTRIBUTED MOST OF THE TIME, SO LITTLE WEIGHTING TO BE DONE ON PERSONS 12+. WE EXPECT NO DIFFERENCE IN AQH RATING 951 OF THE TIME. .1 RATING POINT 51 OF THE TIME ANY IMPACT WILL HAVE NO SYSTEMATIC EFFECT BY STATION TYPE OR FORMAT, BECAUSE SAMPLE IMBALANCE BY MONTH IS NOT SYSTEMATIC ...NO DISRUPTIVE EFFECT ON TRENDS ARBITRON RATINGS J [10 J RAG/MARCH 86 _24_ C. KUMMER www.americanradiohistory.com

Q 2) CONTROL DATA PRIVATE WHAT ABOUT ARBITRENDS? THE INTRODUCTION OF CALENDAR TIME WEIGHTING ON THE MARGIN ALLOWS US TO ALIGN THE METHODOLOGY FOR PRODUCING ARBITRENDS ROLLING AVERAGES WITH THAT OF THE QUARTERLY REPORTS CURRENTLY: JH 3 MONTH 2 MONTH 1 ,10N 3 AFTER THE CHANGE: MONTH 2 MONTH 3 MONTH 1 ARBITRON RATINGS raz RAC/MARCH 86 C. KUMMER -25- www.americanradiohistory.com