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2 years ago

1. A researcher is interested in whether drinking different sources of caffeine (tea vs. coffee) leads

Mathematics

1 answer:

g100num [7]2 years ago

3 0

The researcher's scientific/alternative hypothesis is:

Different sources of caffeine leads to differences in women's attentional control performance.

The researcher's null hypothesis is:

Different sources of caffeine leads to no difference in women's attentional control performance.

The type of sample which the researcher is using is:

Probability sampling.

A disadvantage to using this sample type is:

It is time consuming.

The thing which the researcher can conclude about these data is:

It is conclusive based on the reaction of the women to the independent variables.

If, in the population, women actually show NO difference in attentional control performance after drinking black tea versus coffee, the type of statistical error which the researcher has made is:

Type I error

<h3>What is a Scientific Hypothesis?</h3>

This refers to the difference between two variables which is discovered during a scientific research and is an observed pattern.

Read more about scientific hypothesis here:
brainly.com/question/896413

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Hi guys can someone please help me with these questions please

Zinaida [17]

Hi There!

----------------------------------

Question 2:

Obviously the right equation for this question is Point Slope Form.

Point Slope Form: y - y1 = m(x - x1)

y1 = -1

x1 = 3

m = 2

Question 2 Answer: y + 1 = 2(x - 3)

----------------------------------

Question 3:

Again use point slope form.

Find Slope:

7 - 1 = 6

-2 - 1 = -3

6/-3 = -2

Question 3 Answer: y - 1 = -2(x - 1)

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Hope This Helps :)

6 0

3 years ago

The three cards below form a number pattern

S_A_V [24]

What three cards I don’t see anything and this is just an statement

4 0

3 years ago

Read 2 more answers

preliminary sample of 100 labourers was selected from a population of 5000 labourers by simple random sampling. It was found tha

VladimirAG [237]

Answer:

$n=\frac{0.4(1-0.4)}{(\frac{0.05}{1.96})^2}=368.79$

n=369

Step-by-step explanation:

1) Notation and definitions

$X=40$ number of the selected labourers opt for a new incentive scheme.

$n=100$ random sample taken

$\hat p=\frac{40}{100}=0.4$ estimated proportion of the selected labourers opt for a new incentive scheme.

$p$ true population proportion of the selected labourers opt for a new incentive scheme.

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

2) Solution tot he problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.05$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

And replacing into equation (b) the values from part a we got:

$n=\frac{0.4(1-0.4)}{(\frac{0.05}{1.96})^2}=368.79$

And rounded up we have that n=369

8 0

3 years ago

Do anyone know this? Please no link <3

ddd [48]

Answer:

40 cm

Step-by-step explanation:

Perimeter = the sum of all sides

5 0

3 years ago

What is 38.3 minus -1.2?

fenix001 [56]

(38.3 - -1.2) = 39.5

Anytime you have two minuses beside each other, you add.
If you have a plus sign in the middle, but one of the numbers is negative you subtract.

Hope that makes sense ! (:

6 0

3 years ago