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A market researcher believes that brand perception of one of the company's products may vary between different groups. After interviewing 307 persons, the following data was compiled. Can we conclude that brand perception is dependent on age?

Age Favorable Unfavorable Neutral Total
18-30 67 24 20 111
30-45 50 14 16 80
Over 45 69 41 26 116
Total 186 59 62 307
Find the value of the test statistic.

User Jjujuma
by
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1 Answer

7 votes

Answer:

The value for the Chi -square test statistics = 1.149

Explanation:

The observed value Table can be shown better as:

Observed Value

Age Favorable Unfavorable Neutral Total

18-30 67 24 20 111

30-45 50 14 16 80

Over 45 69 21 26 116

Total 186 59 62 307

NOTE: when computing the question, in the third row and the second column, there is a mistake , the value is supposed to be 21 and not 41 because :

69 +21+ 26 will eventually give = 116

69 + 41 + 26 = 136

With that error being fix , let's get started.

Expected Value

The expected value can be determined by using the formula:


Expected \ Value = ( row \ total * column \ total )/(grand \ total )

For 67; (111 * 186)/307 = 67.251

For 24 : (111 * 59)/307 = 21.332

For 20 : (111 * 62)/307 = 22.417

For 50 :(80*186)/307 = 48.469

For 14 : (80* 59)/307 = 15.375

For 16 : ( 0 * 62)/307 = 16.156

For 69 : (116 * 186)/307 = 70.280

For 21 : (116* 59)/307 = 22.293

For 26 : (116*62)/307 = 23.427

Expected Value :

Age Favorable Unfavorable Neutral Total

18-30 67.251 21.332 22.417 111

30-45 48.469 15.375 16.156 80

Over 45 70.280 22.293 23.427 116

Total 186 59 62 307

The Chi - square test statistics =
((observed \ value - Expected \ value)^2)/(Expected \ value)

For 67.251 : ( 67 - 67.251)²/67.251 = 0.0009

For 21.332 : ( 24 - 21.332)²/21.332 = 0.3337

For 22.417 : ( 20 - 22.417)²/ 22.417 = 0.2606

For 48.469 : ( 50 - 48.469)²/ 48.469 = 0.0484

For 15.375 : ( 14 - 15.375)²/ 15.375 = 0.1230

For 16.156 : ( 16 - 16.156)²/ 16.156 = 0.0015

For 70.280 : ( 69 - 70.280)²/ 70.280 = 0.0233

For 22.293 : ( 21 - 22.293)²/ 22.293 = 0.0750

For 23.427 : ( 26 - 23.427)²/ 23.427 = 0.2826

The chi square table is as follows:

Age Favorable Unfavorable Neutral Total

18-30 0.0009 0.3337 0.2606 0.5952

30-45 0.0484 0.1230 0.0015 0.1729

Over 45 0.0233 0.0750 0.2826 0.3809

Total 0.0726 0.5317 0.5447 1.149

The value for the Chi -square test statistics = 1.149

User Anakhand
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