This is from a recent news article about a study on children using drugs: “The researchers analyzed the data to estimate the average age at first-time use for 18 internationally regulated drugs for each year included in the study. Looking at year-to-year trends, they found that the average age at first use had increased for 12 out of 18 drugs, including alcohol, cocaine, ecstasy, hallucinogens, heroin, inhalants, LSD, marijuana, stimulants, and tobacco products such as cigars, cigarettes and smokeless tobacco. For the other six drugs— crack cocaine, methamphetamines, opioids, PCP, sedatives, and tranquilizers—they found no statistically significant changes in the age at first use.”

Question
This is from a recent news article about a study on children using drugs: “The researchers analyzed the data to estimate the average age at first-time use for 18 internationally regulated drugs for each year included in the study. Looking at year-to-year trends, they found that the average age at first use had increased for 12 out of 18 drugs, including alcohol, cocaine, ecstasy, hallucinogens, heroin, inhalants, LSD, marijuana, stimulants, and tobacco products such as cigars, cigarettes and smokeless tobacco. For the other six drugs— crack cocaine, methamphetamines, opioids, PCP, sedatives, and tranquilizers—they found no statistically significant changes in the age at first use.”

Answers (1)

2021-02-12
Step 1
Given
Among the 18 internationally regulated drugs, the average age at first use had increased for 12 out of 18 drugs, including alcohol, cocaine, ecstasy, hallucinogens, heroin, inhalants, LSD, marijuana, stimulants, and tobacco products such as cigars, cigarettes and smokeless tobacco.
For other 6 drugs -crack cocaine, methamphetamine's, opioids, PCP, sedatives, and tranquilizers—they found no statistically significant changes in the age at first use.
Step 2
After the analysis of data to estimate the average age at first time use for 18 internationally regulated drugs, with reference to the year to year trends, it is found that the p value is large when compared to the level of significance and so we say there is no change in average age for first use for six drugs -crack cocaine, methamphetamine's, opioids, PCP, sedatives, and tranquilizers.
0

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$_______ to $________
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\(\displaystyle{b}{e}{g}\in{\left\lbrace{a}{r}{r}{a}{y}\right\rbrace}{\left\lbrace{\left|{c}\right|}{c}{\mid}\right\rbrace}{h}{l}\in{e}&{a}\mp,\ {1}&{a}\mp,\ {2}&{a}\mp,\ {T}{o}{t}{a}{l}\backslash{h}{l}\in{e}{1}&{a}\mp,\ {35}&{a}\mp,\ {147}&{a}\mp,\ {182}\backslash{h}{l}\in{e}&{a}\mp,\ {25.48}&{a}\mp,\ {156.52}&{a}\mp,\backslash{h}{l}\in{e}{2}&{a}\mp,\ {101}&{a}\mp,\ {629}&{a}\mp,\ {730}\backslash{h}{l}\in{e}&{a}\mp,\ {102.20}&{a}\mp,\ {627.80}&{a}\mp,\backslash{h}{l}\in{e}{3}&{a}\mp,\ {28}&{a}\mp,\ {222}&{a}\mp,\ {250}\backslash{h}{l}\in{e}&{a}\mp,\ {35.00}&{a}\mp,\ {215.00}&{a}\mp,\backslash{h}{l}\in{e}{4}&{a}\mp,\ {4}&{a}\mp,\ {34}&{a}\mp,\ {38}\backslash{h}{l}\in{e}&{a}\mp,\ {5.32}&{a}\mp,\ {32.68}&{a}\mp,\backslash{h}{l}\in{e}{T}{o}{t}{a}{l}&{a}\mp,\ {168}&{a}\mp,\ {1032}&{a}\mp,\ {1200}\backslash{h}{l}\in{e}\)
\(\displaystyle{C}{h}{i}{s}{q}={a}\mp,\ {3.557}\ +\ {0.579}\ +\ {a}\mp,\ {0.014}\ +\ {0.002}\ +\ {a}\mp,\ {1.400}\ +\ {0.228}\ +\ {a}\mp,\ {0.328}\ +\ {0.053}={6.161}\)
\(\displaystyle{d}{f}={3}\)
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