The Study
We will receive a list of students from Mrs. Caso, and we will randomly select the juniors and seniors for our survey using Minitab.
SURVEY
Do you have a Facebook account? ______
If you answered yes,
How many Facebook friends do you have? _________
Do you have texting on your phone? ______
If you answered yes,
How many texts do you receive (receive only, not send) per month? _________
BASIC STATISTICS
| Variable | N | N* | Mean | SE Mean | StDev | Min | Q1 | Median | Q3 | Max |
| friends | 52 | 0 | 373.3 | 38.1 | 274.5 | 0 | 177 | 384.5 | 587.5 | 1020 |
| textsrecieved | 52 | 0 | 2638 | 605 | 4361 | 0 | 513 | 1175 | 2875 | 20000 |
LINEAR REGRESSION T TEST
Results with outliers
The regression
equation is
friends = 386 - 0.00489 textsrecieved
| Predictor | Coef | SE Coef | T | P |
| Constant | 386.2 | 44.92 | 8.6 | 0 |
| textsrecieved | -0.00489 | 0.008875 | -0.55 | 0.584 |
S = 276.428 R-Sq = 0.6% R-Sq(adj) = 0.0%
Results without outliers
The regression equation is
friends = 296 + 0.0608 textsrecieved
| Predictor | Coef | SE Coef | T | P |
| Constant | 296.38 | 55.92 | 5.3 | 0 |
| textsrecieved | 0.06077 | 0.02693 | 2.26 | 0.029 |
S = 267.234 R-Sq = 10.0% R-Sq(adj) = 8.0%
CHI-SQUARE TEST
1) π1=Of the people who have Facebook, the proportion that also have texting
2) Ho:π1=0.94
3)Ha= Ho is false
4)a=0.05
5)Test statistic: χ²=Σ((observed cell count-expected cell count)²/(expected cell count))
6) Assumptions: The sample was randomly selected from the population of juniors and seniors at North Olmsted High School. All expected counts were not greater than 5, therefore a chi-square test could not be run validly.