10.2 Means sd Unknown

# 05 level of significance that the mean mpg of m cars

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Unformatted text preview: ue&lt;α H0: μ1 – μ2= D0 Ha: μ1 – μ2≠ D0 reject H0 if tSTAT &lt; –tα/2 or tSTAT &gt; tα/2 or if p-value&lt;α Example What are the hypotheses for testing whether the mean mpg of M cars is greater than the mean mpg of J cars? Specific Motors of Detroit has developed a new automobile known as the M car. 24 M cars and 28 J cars (from Japan) Is μM&gt;μJ? were road tested to compare mpg performance. The sample Hypotheses: statistics are: H0: μM–μJ ≤ 0 M μM Cars Ha: Cars–μJJ &gt; 0 Hypothesis Tests n x s 24 28 29.8 27.3 2.56 test statistic upper tail test lower tail test 1.81 two-tailed test Difference Between 2 Population Means (x1 − x2)− D0 tSTAT = s 2 s22, df 1 + =… n1 n2 H0: μ1 – μ2 ≤ D0 Ha: μ1 – μ2 &gt; D0 reject H0 if tSTAT &gt; tα or p-value&lt;α H0: μ1 – μ2 ≥ D0 Ha: μ1 – μ2 &lt; D0 reject H0 if tSTAT &lt;– tα or p-value&lt;α H0: μ1 – μ2= D0 Ha: μ1 – μ2≠ D0 reject H0 if tSTAT &lt; –tα/2 or tSTAT &gt; tα/2 or if p-value&lt;α Example How can we conclude at 0.05 level of significance that the mean mpg of M cars is greater than the mean mpg of J cars? Specific Motors of Detroit has developed a new automobile known as the M car. 24 M cars and 28 J cars (from Japan) were road tested to compare mpg performance. The sample statistics are: Hypothesis Tests M Cars n x s J Cars 24 28 29.8 27.3 2.56 test statistic upper tail test lower tail test 1.81 two-tailed test Difference Between 2 Population Means (x1 − x2)− D0 tSTAT = s 2 s22 , df = 1 + n1 n2 H0: DM–J ≤ 0 Ha: DM–J &gt; 0 reject H0 if tSTAT &gt; tα or p-value&lt;α H0: μ1 – μ2 ≥ D0 Ha: μ1 – μ2 &lt; D0 reject H0 if tSTAT &lt;– tα or p-value&lt;α H0: μ1 – μ2= D0 Ha: μ1 – μ2≠ D0 reject H0 if tSTAT &lt; –tα/2 or tSTAT &gt; tα/2 or if p-value&lt;α Example How can we conclude at 0.05 level of significance that the mean mpg of M cars is greater than the mean mpg of J cars? Specific Motors of Detroit has developed a new automobile known as the M car. 24 M cars and 28 J cars (from Japan) were road tested to compare Usingα=0.05, reject H0 mpg performance. The sample tSTAT &gt; statistics are: z.05 (critical value approach) tail ; or p-value &lt; 0.05 (p- uppertest M Cars J Cars 24 28 29.8 27.3 value approach) Hypothesis Tests n x s if: test statistic 2.56 lower tail test 1.81 two-tailed test Difference Between 2 Population Means (x1 − x2)− D0 tSTAT = s 2 s22 , df = 1 + n1 n2 H0: DM–J ≤ 0 Ha: DM–J &gt; 0 reject H0 if tSTAT &gt; tα or p-value&lt;α H0: μ1 – μ2 ≥ D0 Ha: μ1 – μ2 &lt; D0 reject H0 if tSTAT &lt;– tα or p-value&lt;α H0: μ1 – μ2= D0 Ha: μ1 – μ2≠ D0 reject H0 if tSTAT &lt; –tα/2 or tSTAT &gt; tα/2 or if p-value&lt;α Example What is the value of the tSTAT (test statistic)? Specific Motors of Detroit has developed a new automobile known as the M car. 24 M cars and 28 J cars (from Japan) were road tested to compare mpg performance. The sample statistics are: M Cars J Cars Hypothesis Tests n x 24 27.3 s...
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## This document was uploaded on 03/05/2014.

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