As challenges to Facebook mount from consumer organizations, politicians and journalists, the company's leadership remains convinced that its recent crises are primarily public relations problems, according to people at the company. Mark Zuckerberg, Facebook's chief executive officer, and Sheryl Sandberg, the company's chief operating officer, believe Facebook's negative image is a public relations problem that stems from a bungled press strategy and sensational media coverage, not a structural or philosophical shortcoming that requires a wholesale course correction.