264a Marketing Research 1

Not Lying with Statistics

264a Marketing Research 2

Not Lying with Statistics

• Aggregation - When do summary numbers represent the underlying detail?

• Cross Tabulation - using Pivot Tables to show relations.

• Quadmap - relating importance and performance.

264a Marketing Research 3

Aggregation - When summary numbers reflect the detail.

• Look at the frequency distribution– Is it unimodal and symmetric?

• Unimodal

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264a Marketing Research 4

Aggregation

• Is it symmetric?

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264a Marketing Research 5

Influence of Skew on Mean, Median and Mode

• Mean - the balance point of a distribution.

• Median - the 50th percentile.

• Mode - most frequently occurring point.

264a Marketing Research 6

Influence of Skew

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264a Marketing Research 7

Influence of Kurtosis

• Platykurtic - fat and flat

• Leptokurtic - tall and skinny

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264a Marketing Research 8

Influence of Kurtosis

• Platykurtic - the average reflects each period.

• Leptokurtic - more precise information exists.

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264a Marketing Research 9

When you hear comparisons

• Are means (averages) being compared?

• Are shapes being compared?– Unimodal vs. bimodal– Symmetric vs. skewed– Lepto- vs. platykurtic

264a Marketing Research 10

The average temperature:West Virginia vs. Alameda, CA

56 degrees vs. 57 degrees

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264a Marketing Research 11

Association in Tables

• Question -- Are ratings of how much consumers Like a brand related to their Top Box rating of Intention to Purchase the brand?

264a Marketing Research 12

Association in Tables

Intent to PurchaseAll No Top Box Total ProbabilitiesLike 116 246 362 0.32 0.68 0.36Dislike 522 116 638 0.82 0.18 0.64

638 362 1000 0.64 0.36 1

If you Like the brand you are much more likely to check the Top Box on the Intent-to-Purchase scale.

264a Marketing Research 13

Could this be the result of aggregating different consumers?

Intent to PurchaseUsers No Top Box Total ProbabilitiesLike 60 240 300 0.20 0.80 0.80Dislike 15 60 75 0.20 0.80 0.20

75 300 375 0.20 0.80 1

Intent to PurchaseNonusers No Top Box Total ProbabilitiesLike 56 6 62 0.90 0.10 0.10Dislike 507 56 563 0.90 0.10 0.90

563 62 625 0.90 0.10 1

264a Marketing Research 14

Using Pivot TablesUser 1

Count of TopBox TopBoxLike 0 1 Grand Total0 15 60 751 60 240 300Grand Total 75 300 375

User 0

Count of TopBox TopBoxLike 0 1 Grand Total0 507 56 5631 56 6 62Grand Total 563 62 625

User (All)

Count of TopBox TopBoxLike 0 1 Grand Total0 522 116 6381 116 246 362Grand Total 638 362 1000